Title: | Poisson Lognormal Models |
Version: | 1.2.2 |
Description: | The Poisson-lognormal model and variants (Chiquet, Mariadassou and Robin, 2021 <doi:10.3389/fevo.2021.588292>) can be used for a variety of multivariate problems when count data are at play, including principal component analysis for count data, discriminant analysis, model-based clustering and network inference. Implements variational algorithms to fit such models accompanied with a set of functions for visualization and diagnostic. |
URL: | https://pln-team.github.io/PLNmodels/ |
BugReports: | https://github.com/pln-team/PLNmodels/issues |
License: | GPL (≥ 3) |
Depends: | R (≥ 4.1.0) |
Imports: | cli, corrplot, dplyr, future, future.apply, ggplot2, glassoFast, grDevices, grid, gridExtra, igraph, magrittr, MASS, Matrix, methods, nloptr, parallel, pscl, purrr, R6, Rcpp, rlang, scales, stats, tidyr, torch |
Suggests: | factoextra, knitr, rmarkdown, spelling, testthat |
LinkingTo: | nloptr, Rcpp, RcppArmadillo |
VignetteBuilder: | knitr |
Encoding: | UTF-8 |
Language: | en-US |
LazyData: | true |
RoxygenNote: | 7.3.2 |
Collate: | 'PLNfit-class.R' 'PLN.R' 'PLNLDA.R' 'PLNLDAfit-S3methods.R' 'PLNLDAfit-class.R' 'PLNPCA.R' 'PLNPCAfamily-S3methods.R' 'PLNfamily-class.R' 'PLNPCAfamily-class.R' 'PLNPCAfit-S3methods.R' 'PLNPCAfit-class.R' 'PLNfamily-S3methods.R' 'PLNfit-S3methods.R' 'PLNmixture.R' 'PLNmixturefamily-S3methods.R' 'PLNmixturefamily-class.R' 'PLNmixturefit-S3methods.R' 'PLNmixturefit-class.R' 'PLNmodels-package.R' 'PLNnetwork.R' 'PLNnetworkfamily-S3methods.R' 'PLNnetworkfamily-class.R' 'PLNnetworkfit-S3methods.R' 'PLNnetworkfit-class.R' 'RcppExports.R' 'ZIPLNfit-class.R' 'ZIPLN.R' 'ZIPLNfit-S3methods.R' 'ZIPLNnetwork.R' 'barents.R' 'import_utils.R' 'mollusk.R' 'oaks.R' 'plot_utils.R' 'scRNA.R' 'trichoptera.R' 'utils-pipe.R' 'utils-zipln.R' 'utils.R' 'zzz.R' |
NeedsCompilation: | yes |
Packaged: | 2025-03-21 11:05:39 UTC; jchiquet |
Author: | Julien Chiquet |
Maintainer: | Julien Chiquet <julien.chiquet@inrae.fr> |
Repository: | CRAN |
Date/Publication: | 2025-03-21 17:40:06 UTC |
PLNmodels: Poisson Lognormal Models
Description
The Poisson-lognormal model and variants (Chiquet, Mariadassou and Robin, 2021 doi:10.3389/fevo.2021.588292) can be used for a variety of multivariate problems when count data are at play, including principal component analysis for count data, discriminant analysis, model-based clustering and network inference. Implements variational algorithms to fit such models accompanied with a set of functions for visualization and diagnostic.
Author(s)
Maintainer: Julien Chiquet julien.chiquet@inrae.fr (ORCID)
Authors:
Mahendra Mariadassou mahendra.mariadassou@inrae.fr (ORCID)
Stéphane Robin stephane.robin@inrae.fr
François Gindraud francois.gindraud@gmail.com
Other contributors:
Julie Aubert julie.aubert@inrae.fr [contributor]
Bastien Batardière bastien.batardiere@inrae.fr [contributor]
Giovanni Poggiato giov.poggiato@gmail.com [contributor]
Cole Trapnell coletrap@uw.edu [contributor]
Maddy Duran duran@uw.edu [contributor]
See Also
Useful links:
Pipe operator
Description
See magrittr::%>%
for details.
Usage
lhs %>% rhs
An R6 Class to virtually represent a collection of network fits
Description
The functions PLNnetwork()
and ZIPLNnetwork()
both produce an instance of this class, which can be thought of as a vector of PLNnetworkfit
s ZIPLNfit_sparse
s (indexed by penalty parameter)
This class comes with a set of methods mostly used to compare
network fits (in terms of goodness of fit) or extract one from
the family (based on penalty parameter and/or goodness of it).
See the documentation for getBestModel()
,
getModel()
and plot() for the user-facing ones.
Super class
PLNmodels::PLNfamily
-> Networkfamily
Active bindings
penalties
the sparsity level of the network in the successively fitted models
stability_path
the stability path of each edge as returned by the stars procedure
stability
mean edge stability along the penalty path
criteria
a data frame with the values of some criteria (variational log-likelihood, (E)BIC, ICL and R2, stability) for the collection of models / fits BIC, ICL and EBIC are defined so that they are on the same scale as the model log-likelihood, i.e. with the form, loglik - 0.5 penalty
Methods
Public methods
Inherited methods
Method new()
Initialize all models in the collection
Usage
Networkfamily$new(penalties, data, control)
Arguments
penalties
a vector of positive real number controlling the level of sparsity of the underlying network.
data
a named list used internally to carry the data matrices
control
a list for controlling the optimization.
Returns
Update all network fits in the family with smart starting values
Method optimize()
Call to the C++ optimizer on all models of the collection
Usage
Networkfamily$optimize(data, config)
Arguments
data
a named list used internally to carry the data matrices
config
a list for controlling the optimization.
Method coefficient_path()
Extract the regularization path of a Networkfamily
Usage
Networkfamily$coefficient_path(precision = TRUE, corr = TRUE)
Arguments
precision
Logical. Should the regularization path be extracted from the precision matrix Omega (
TRUE
, default) or from the variance matrix Sigma (FALSE
)corr
Logical. Should the matrix be transformed to (partial) correlation matrix before extraction? Defaults to
TRUE
Method getBestModel()
Extract the best network in the family according to some criteria
Usage
Networkfamily$getBestModel(crit = c("BIC", "EBIC", "StARS"), stability = 0.9)
Arguments
crit
character. Criterion used to perform the selection. If "StARS" is chosen but
$stability
field is empty, will compute stability path.stability
Only used for "StARS" criterion. A scalar indicating the target stability (= 1 - 2 beta) at which the network is selected. Default is
0.9
.
Details
For BIC and EBIC criteria, higher is better.
Method plot()
Display various outputs (goodness-of-fit criteria, robustness, diagnostic) associated with a collection of network fits (a Networkfamily
)
Usage
Networkfamily$plot( criteria = c("loglik", "pen_loglik", "BIC", "EBIC"), reverse = FALSE, log.x = TRUE )
Arguments
criteria
vector of characters. The criteria to plot in
c("loglik", "pen_loglik", "BIC", "EBIC")
. Defaults to all of them.reverse
A logical indicating whether to plot the value of the criteria in the "natural" direction (loglik - 0.5 penalty) or in the "reverse" direction (-2 loglik + penalty). Default to FALSE, i.e use the natural direction, on the same scale as the log-likelihood.
log.x
logical: should the x-axis be represented in log-scale? Default is
TRUE
.
Returns
a ggplot2::ggplot
graph
Method plot_stars()
Plot stability path
Usage
Networkfamily$plot_stars(stability = 0.9, log.x = TRUE)
Arguments
stability
scalar: the targeted level of stability using stability selection. Default is
0.9
.log.x
logical: should the x-axis be represented in log-scale? Default is
TRUE
.
Returns
a ggplot2::ggplot
graph
Method plot_objective()
Plot objective value of the optimization problem along the penalty path
Usage
Networkfamily$plot_objective()
Returns
a ggplot2::ggplot
graph
Method show()
User friendly print method
Usage
Networkfamily$show()
Method clone()
The objects of this class are cloneable with this method.
Usage
Networkfamily$clone(deep = FALSE)
Arguments
deep
Whether to make a deep clone.
See Also
The functions PLNnetwork()
, ZIPLNnetwork()
and the classes PLNnetworkfit
, ZIPLNfit_sparse
Poisson lognormal model
Description
Fit the multivariate Poisson lognormal model with a variational algorithm. Use the (g)lm syntax for model specification (covariates, offsets, weights).
Usage
PLN(formula, data, subset, weights, control = PLN_param())
Arguments
formula |
an object of class "formula": a symbolic description of the model to be fitted. |
data |
an optional data frame, list or environment (or object coercible by as.data.frame to a data frame) containing the variables in the model. If not found in data, the variables are taken from environment(formula), typically the environment from which PLN is called. |
subset |
an optional vector specifying a subset of observations to be used in the fitting process. |
weights |
an optional vector of observation weights to be used in the fitting process. |
control |
a list-like structure for controlling the optimization, with default generated by |
Value
an R6 object with class PLNfit
See Also
The class PLNfit
and the configuration function PLN_param()
Examples
data(trichoptera)
trichoptera <- prepare_data(trichoptera$Abundance, trichoptera$Covariate)
myPLN <- PLN(Abundance ~ 1, data = trichoptera)
Poisson lognormal model towards Linear Discriminant Analysis
Description
Fit the Poisson lognormal for LDA with a variational algorithm. Use the (g)lm syntax for model specification (covariates, offsets).
Usage
PLNLDA(formula, data, subset, weights, grouping, control = PLN_param())
Arguments
formula |
an object of class "formula": a symbolic description of the model to be fitted. |
data |
an optional data frame, list or environment (or object coercible by as.data.frame to a data frame) containing the variables in the model. If not found in data, the variables are taken from environment(formula), typically the environment from which lm is called. |
subset |
an optional vector specifying a subset of observations to be used in the fitting process. |
weights |
an optional vector of observation weights to be used in the fitting process. |
grouping |
a factor specifying the class of each observation used for discriminant analysis. |
control |
a list-like structure for controlling the optimization, with default generated by |
Details
The parameter control
is a list controlling the optimization with the following entries:
"covariance" character setting the model for the covariance matrix. Either "full" or "spherical". Default is "full".
"trace" integer for verbosity.
"inception" Set up the initialization. By default, the model is initialized with a multivariate linear model applied on log-transformed data. However, the user can provide a PLNfit (typically obtained from a previous fit), which often speed up the inference.
"ftol_rel" stop when an optimization step changes the objective function by less than ftol multiplied by the absolute value of the parameter. Default is 1e-8
"ftol_abs" stop when an optimization step changes the objective function by less than ftol multiplied by the absolute value of the parameter. Default is 0
"xtol_rel" stop when an optimization step changes every parameters by less than xtol multiplied by the absolute value of the parameter. Default is 1e-6
"xtol_abs" stop when an optimization step changes every parameters by less than xtol multiplied by the absolute value of the parameter. Default is 0
"maxeval" stop when the number of iteration exceeds maxeval. Default is 10000
"maxtime" stop when the optimization time (in seconds) exceeds maxtime. Default is -1 (no restriction)
"algorithm" the optimization method used by NLOPT among LD type, i.e. "CCSAQ", "MMA", "LBFGS", "VAR1", "VAR2". See NLOPT documentation for further details. Default is "CCSAQ".
Value
an R6 object with class PLNLDAfit()
See Also
The class PLNLDAfit
Examples
data(trichoptera)
trichoptera <- prepare_data(trichoptera$Abundance, trichoptera$Covariate)
myPLNLDA <- PLNLDA(Abundance ~ 1, grouping = Group, data = trichoptera)
Control of a PLNLDA fit
Description
Helper to define list of parameters to control the PLNLDA fit. All arguments have defaults.
Usage
PLNLDA_param(
backend = c("nlopt", "torch"),
trace = 1,
covariance = c("full", "diagonal", "spherical"),
config_post = list(),
config_optim = list(),
inception = NULL
)
Arguments
backend |
optimization back used, either "nlopt" or "torch". Default is "nlopt" |
trace |
a integer for verbosity. |
covariance |
character setting the model for the covariance matrix. Either "full", "diagonal" or "spherical". Default is "full". |
config_post |
a list for controlling the post-treatments (optional bootstrap, jackknife, R2, etc.). See details |
config_optim |
a list for controlling the optimizer (either "nlopt" or "torch" backend). See details |
inception |
Set up the parameters initialization: by default, the model is initialized with a multivariate linear model applied on log-transformed data, and with the same formula as the one provided by the user. However, the user can provide a PLNfit (typically obtained from a previous fit), which sometimes speeds up the inference. |
Details
The list of parameters config_optim
controls the optimizers. When "nlopt" is chosen the following entries are relevant
"algorithm" the optimization method used by NLOPT among LD type, e.g. "CCSAQ", "MMA", "LBFGS". See NLOPT documentation for further details. Default is "CCSAQ".
"maxeval" stop when the number of iteration exceeds maxeval. Default is 10000
"ftol_rel" stop when an optimization step changes the objective function by less than ftol multiplied by the absolute value of the parameter. Default is 1e-8
"xtol_rel" stop when an optimization step changes every parameters by less than xtol multiplied by the absolute value of the parameter. Default is 1e-6
"ftol_abs" stop when an optimization step changes the objective function by less than ftol_abs. Default is 0.0 (disabled)
"xtol_abs" stop when an optimization step changes every parameters by less than xtol_abs. Default is 0.0 (disabled)
"maxtime" stop when the optimization time (in seconds) exceeds maxtime. Default is -1 (disabled)
When "torch" backend is used (only for PLN and PLNLDA for now), the following entries are relevant:
"algorithm" the optimizer used by torch among RPROP (default), RMSPROP, ADAM and ADAGRAD
"maxeval" stop when the number of iteration exceeds maxeval. Default is 10 000
"numepoch" stop training once this number of epochs exceeds numepoch. Set to -1 to enable infinite training. Default is 1 000
"num_batch" number of batches to use during training. Defaults to 1 (use full dataset at each epoch)
"ftol_rel" stop when an optimization step changes the objective function by less than ftol multiplied by the absolute value of the parameter. Default is 1e-8
"xtol_rel" stop when an optimization step changes every parameters by less than xtol multiplied by the absolute value of the parameter. Default is 1e-6
"lr" learning rate. Default is 0.1.
"momentum" momentum factor. Default is 0 (no momentum). Only used in RMSPROP
"weight_decay" Weight decay penalty. Default is 0 (no decay). Not used in RPROP
"step_sizes" pair of minimal (default: 1e-6) and maximal (default: 50) allowed step sizes. Only used in RPROP
"etas" pair of multiplicative increase and decrease factors. Default is (0.5, 1.2). Only used in RPROP
"centered" if TRUE, compute the centered RMSProp where the gradient is normalized by an estimation of its variance weight_decay (L2 penalty). Default to FALSE. Only used in RMSPROP
The list of parameters config_post
controls the post-treatment processing (for most PLN*()
functions), with the following entries (defaults may vary depending on the specific function, check config_post_default_*
for defaults values):
jackknife boolean indicating whether jackknife should be performed to evaluate bias and variance of the model parameters. Default is FALSE.
bootstrap integer indicating the number of bootstrap resamples generated to evaluate the variance of the model parameters. Default is 0 (inactivated).
variational_var boolean indicating whether variational Fisher information matrix should be computed to estimate the variance of the model parameters (highly underestimated). Default is FALSE.
sandwich_var boolean indicating whether sandwich estimation should be used to estimate the variance of the model parameters (highly underestimated). Default is FALSE.
rsquared boolean indicating whether approximation of R2 based on deviance should be computed. Default is TRUE
Value
list of parameters configuring the fit.
An R6 Class to represent a PLNfit in a LDA framework
Description
The function PLNLDA()
produces an instance of an object with class PLNLDAfit
.
This class comes with a set of methods, some of them being useful for the user:
See the documentation for the methods inherited by PLNfit()
, the plot()
method for
LDA visualization and predict()
method for prediction
Super class
PLNmodels::PLNfit
-> PLNLDAfit
Active bindings
rank
the dimension of the current model
nb_param
number of parameters in the current PLN model
model_par
a list with the matrices associated with the estimated parameters of the PLN model: B (covariates), Sigma (latent covariance), C (latent loadings), P (latent position) and Mu (group means)
percent_var
the percent of variance explained by each axis
corr_map
a matrix of correlations to plot the correlation circles
scores
a matrix of scores to plot the individual factor maps
group_means
a matrix of group mean vectors in the latent space.
Methods
Public methods
Inherited methods
Method new()
Initialize a PLNLDAfit
object
Usage
PLNLDAfit$new( grouping, responses, covariates, offsets, weights, formula, control )
Arguments
grouping
a factor specifying the class of each observation used for discriminant analysis.
responses
the matrix of responses (called Y in the model). Will usually be extracted from the corresponding field in PLNfamily-class
covariates
design matrix (called X in the model). Will usually be extracted from the corresponding field in PLNfamily-class
offsets
offset matrix (called O in the model). Will usually be extracted from the corresponding field in PLNfamily-class
weights
an optional vector of observation weights to be used in the fitting process.
formula
model formula used for fitting, extracted from the formula in the upper-level call
control
list controlling the optimization and the model
Method optimize()
Compute group means and axis of the LDA (noted B in the model) in the latent space, update corresponding fields
Usage
PLNLDAfit$optimize(grouping, responses, covariates, offsets, weights, config)
Arguments
grouping
a factor specifying the class of each observation used for discriminant analysis.
responses
the matrix of responses (called Y in the model). Will usually be extracted from the corresponding field in PLNfamily-class
covariates
design matrix. Automatically built from the covariates and the formula from the call
offsets
offset matrix (called O in the model). Will usually be extracted from the corresponding field in PLNfamily-class
weights
an optional vector of observation weights to be used in the fitting process.
config
list controlling the optimization
X
Abundance matrix.
Method postTreatment()
Update R2, fisher and std_err fields and visualization
Usage
PLNLDAfit$postTreatment( grouping, responses, covariates, offsets, config_post, config_optim )
Arguments
grouping
a factor specifying the class of each observation used for discriminant analysis.
responses
the matrix of responses (called Y in the model). Will usually be extracted from the corresponding field in PLNfamily-class
covariates
design matrix (called X in the model). Will usually be extracted from the corresponding field in PLNfamily-class
offsets
offset matrix (called O in the model). Will usually be extracted from the corresponding field in PLNfamily-class
config_post
a list for controlling the post-treatments (optional bootstrap, jackknife, R2, etc.).
config_optim
list controlling the optimization parameters
Method setVisualization()
Compute LDA scores in the latent space and update corresponding fields.
Usage
PLNLDAfit$setVisualization(scale.unit = FALSE)
Arguments
scale.unit
Logical. Should LDA scores be rescaled to have unit variance
Method plot_individual_map()
Plot the factorial map of the LDA
Usage
PLNLDAfit$plot_individual_map( axes = 1:min(2, self$rank), main = "Individual Factor Map", plot = TRUE )
Arguments
axes
numeric, the axes to use for the plot when map = "individual" or "variable". Default it c(1,min(rank))
main
character. A title for the single plot (individual or variable factor map). If NULL (the default), an hopefully appropriate title will be used.
plot
logical. Should the plot be displayed or sent back as ggplot object
Returns
a ggplot2::ggplot
graphic
Method plot_correlation_map()
Plot the correlation circle of a specified axis for a PLNLDAfit
object
Usage
PLNLDAfit$plot_correlation_map( axes = 1:min(2, self$rank), main = "Variable Factor Map", cols = "default", plot = TRUE )
Arguments
axes
numeric, the axes to use for the plot when map = "individual" or "variable". Default it c(1,min(rank))
main
character. A title for the single plot (individual or variable factor map). If NULL (the default), an hopefully appropriate title will be used.
cols
a character, factor or numeric to define the color associated with the variables. By default, all variables receive the default color of the current palette.
plot
logical. Should the plot be displayed or sent back as ggplot object
Returns
a ggplot2::ggplot
graphic
Method plot_LDA()
Plot a summary of the PLNLDAfit
object
Usage
PLNLDAfit$plot_LDA( nb_axes = min(3, self$rank), var_cols = "default", plot = TRUE )
Arguments
nb_axes
scalar: the number of axes to be considered when map = "both". The default is min(3,rank).
var_cols
a character, factor or numeric to define the color associated with the variables. By default, all variables receive the default color of the current palette.
plot
logical. Should the plot be displayed or sent back as ggplot object
Returns
a grob
object
Method predict()
Predict group of new samples
Usage
PLNLDAfit$predict( newdata, type = c("posterior", "response", "scores"), scale = c("log", "prob"), prior = NULL, control = PLN_param(backend = "nlopt"), envir = parent.frame() )
Arguments
newdata
A data frame in which to look for variables, offsets and counts with which to predict.
type
The type of prediction required. The default are posterior probabilities for each group (in either unnormalized log-scale or natural probabilities, see "scale" for details), "response" is the group with maximal posterior probability and "scores" is the average score along each separation axis in the latent space, with weights equal to the posterior probabilities.
scale
The scale used for the posterior probability. Either log-scale ("log", default) or natural probabilities summing up to 1 ("prob").
prior
User-specified prior group probabilities in the new data. If NULL (default), prior probabilities are computed from the learning set.
control
a list for controlling the optimization. See
PLN()
for details.envir
Environment in which the prediction is evaluated
Method show()
User friendly print method
Usage
PLNLDAfit$show()
Method clone()
The objects of this class are cloneable with this method.
Usage
PLNLDAfit$clone(deep = FALSE)
Arguments
deep
Whether to make a deep clone.
See Also
The function PLNLDA
.
Examples
## Not run:
data(trichoptera)
trichoptera <- prepare_data(trichoptera$Abundance, trichoptera$Covariate)
myPLNLDA <- PLNLDA(Abundance ~ 1, grouping = Group, data = trichoptera)
class(myPLNLDA)
print(myPLNLDA)
## End(Not run)
An R6 Class to represent a PLNfit in a LDA framework with diagonal covariance
Description
The function PLNLDA()
produces an instance of an object with class PLNLDAfit
.
This class comes with a set of methods, some of them being useful for the user:
See the documentation for the methods inherited by PLNfit()
, the plot()
method for
LDA visualization and predict()
method for prediction
Super classes
PLNmodels::PLNfit
-> PLNmodels::PLNLDAfit
-> PLNLDAfit_diagonal
Active bindings
vcov_model
character: the model used for the residual covariance
nb_param
number of parameters in the current PLN model
Methods
Public methods
Inherited methods
PLNmodels::PLNfit$optimize_vestep()
PLNmodels::PLNfit$predict_cond()
PLNmodels::PLNfit$print()
PLNmodels::PLNfit$update()
PLNmodels::PLNLDAfit$optimize()
PLNmodels::PLNLDAfit$plot_LDA()
PLNmodels::PLNLDAfit$plot_correlation_map()
PLNmodels::PLNLDAfit$plot_individual_map()
PLNmodels::PLNLDAfit$postTreatment()
PLNmodels::PLNLDAfit$predict()
PLNmodels::PLNLDAfit$setVisualization()
PLNmodels::PLNLDAfit$show()
Method new()
Initialize a PLNfit
model
Usage
PLNLDAfit_diagonal$new( grouping, responses, covariates, offsets, weights, formula, control )
Arguments
grouping
a factor specifying the class of each observation used for discriminant analysis.
responses
the matrix of responses (called Y in the model). Will usually be extracted from the corresponding field in PLNfamily-class
covariates
design matrix (called X in the model). Will usually be extracted from the corresponding field in PLNfamily-class
offsets
offset matrix (called O in the model). Will usually be extracted from the corresponding field in PLNfamily-class
weights
an optional vector of observation weights to be used in the fitting process.
formula
model formula used for fitting, extracted from the formula in the upper-level call
control
a list for controlling the optimization. See details.
Method clone()
The objects of this class are cloneable with this method.
Usage
PLNLDAfit_diagonal$clone(deep = FALSE)
Arguments
deep
Whether to make a deep clone.
Examples
## Not run:
data(trichoptera)
trichoptera <- prepare_data(trichoptera$Abundance, trichoptera$Covariate)
myPLNLDA <- PLNLDA(Abundance ~ 1, data = trichoptera, control = PLN_param(covariance = "diagonal"))
class(myPLNLDA)
print(myPLNLDA)
## End(Not run)
Poisson lognormal model towards Principal Component Analysis
Description
Fit the PCA variants of the Poisson lognormal with a variational algorithm. Use the (g)lm syntax for model specification (covariates, offsets).
Usage
PLNPCA(formula, data, subset, weights, ranks = 1:5, control = PLNPCA_param())
Arguments
formula |
an object of class "formula": a symbolic description of the model to be fitted. |
data |
an optional data frame, list or environment (or object coercible by as.data.frame to a data frame) containing the variables in the model. If not found in data, the variables are taken from environment(formula), typically the environment from which lm is called. |
subset |
an optional vector specifying a subset of observations to be used in the fitting process. |
weights |
an optional vector of observation weights to be used in the fitting process. |
ranks |
a vector of integer containing the successive ranks (or number of axes to be considered) |
control |
a list-like structure for controlling the optimization, with default generated by |
Value
an R6 object with class PLNPCAfamily
, which contains
a collection of models with class PLNPCAfit
See Also
The classes PLNPCAfamily
and PLNPCAfit
, and the configuration function PLNPCA_param()
.
Examples
#' ## Use future to dispatch the computations on 2 workers
## Not run:
future::plan("multisession", workers = 2)
## End(Not run)
data(trichoptera)
trichoptera <- prepare_data(trichoptera$Abundance, trichoptera$Covariate)
myPCA <- PLNPCA(Abundance ~ 1 + offset(log(Offset)), data = trichoptera, ranks = 1:5)
# Shut down parallel workers
## Not run:
future::plan("sequential")
## End(Not run)
Control of PLNPCA fit
Description
Helper to define list of parameters to control the PLNPCA fit. All arguments have defaults.
Usage
PLNPCA_param(
backend = "nlopt",
trace = 1,
config_optim = list(),
config_post = list(),
inception = NULL
)
Arguments
backend |
optimization back used, either "nlopt" or "torch". Default is "nlopt" |
trace |
a integer for verbosity. |
config_optim |
a list for controlling the optimizer (either "nlopt" or "torch" backend). See details |
config_post |
a list for controlling the post-treatments (optional bootstrap, jackknife, R2, etc.). See details |
inception |
Set up the parameters initialization: by default, the model is initialized with a multivariate linear model applied on log-transformed data, and with the same formula as the one provided by the user. However, the user can provide a PLNfit (typically obtained from a previous fit), which sometimes speeds up the inference. |
Details
The list of parameters config_optim
controls the optimizers. When "nlopt" is chosen the following entries are relevant
"algorithm" the optimization method used by NLOPT among LD type, e.g. "CCSAQ", "MMA", "LBFGS". See NLOPT documentation for further details. Default is "CCSAQ".
"maxeval" stop when the number of iteration exceeds maxeval. Default is 10000
"ftol_rel" stop when an optimization step changes the objective function by less than ftol multiplied by the absolute value of the parameter. Default is 1e-8
"xtol_rel" stop when an optimization step changes every parameters by less than xtol multiplied by the absolute value of the parameter. Default is 1e-6
"ftol_abs" stop when an optimization step changes the objective function by less than ftol_abs. Default is 0.0 (disabled)
"xtol_abs" stop when an optimization step changes every parameters by less than xtol_abs. Default is 0.0 (disabled)
"maxtime" stop when the optimization time (in seconds) exceeds maxtime. Default is -1 (disabled)
When "torch" backend is used (only for PLN and PLNLDA for now), the following entries are relevant:
"algorithm" the optimizer used by torch among RPROP (default), RMSPROP, ADAM and ADAGRAD
"maxeval" stop when the number of iteration exceeds maxeval. Default is 10 000
"numepoch" stop training once this number of epochs exceeds numepoch. Set to -1 to enable infinite training. Default is 1 000
"num_batch" number of batches to use during training. Defaults to 1 (use full dataset at each epoch)
"ftol_rel" stop when an optimization step changes the objective function by less than ftol multiplied by the absolute value of the parameter. Default is 1e-8
"xtol_rel" stop when an optimization step changes every parameters by less than xtol multiplied by the absolute value of the parameter. Default is 1e-6
"lr" learning rate. Default is 0.1.
"momentum" momentum factor. Default is 0 (no momentum). Only used in RMSPROP
"weight_decay" Weight decay penalty. Default is 0 (no decay). Not used in RPROP
"step_sizes" pair of minimal (default: 1e-6) and maximal (default: 50) allowed step sizes. Only used in RPROP
"etas" pair of multiplicative increase and decrease factors. Default is (0.5, 1.2). Only used in RPROP
"centered" if TRUE, compute the centered RMSProp where the gradient is normalized by an estimation of its variance weight_decay (L2 penalty). Default to FALSE. Only used in RMSPROP
The list of parameters config_post
controls the post-treatment processing (for most PLN*()
functions), with the following entries (defaults may vary depending on the specific function, check config_post_default_*
for defaults values):
jackknife boolean indicating whether jackknife should be performed to evaluate bias and variance of the model parameters. Default is FALSE.
bootstrap integer indicating the number of bootstrap resamples generated to evaluate the variance of the model parameters. Default is 0 (inactivated).
variational_var boolean indicating whether variational Fisher information matrix should be computed to estimate the variance of the model parameters (highly underestimated). Default is FALSE.
sandwich_var boolean indicating whether sandwich estimation should be used to estimate the variance of the model parameters (highly underestimated). Default is FALSE.
rsquared boolean indicating whether approximation of R2 based on deviance should be computed. Default is TRUE
Value
list of parameters configuring the fit.
An R6 Class to represent a collection of PLNPCAfit
Description
The function PLNPCA()
produces an instance of this class.
This class comes with a set of methods, some of them being useful for the user:
See the documentation for getBestModel()
,
getModel()
and plot()
.
Super class
PLNmodels::PLNfamily
-> PLNPCAfamily
Active bindings
ranks
the dimensions of the successively fitted models
Methods
Public methods
Inherited methods
Method new()
Initialize all models in the collection.
Usage
PLNPCAfamily$new( ranks, responses, covariates, offsets, weights, formula, control )
Arguments
ranks
the dimensions of the successively fitted models
responses
the matrix of responses common to every models
covariates
the matrix of covariates common to every models
offsets
the matrix of offsets common to every models
weights
the vector of observation weights
formula
model formula used for fitting, extracted from the formula in the upper-level call
control
list controlling the optimization and the model
Method optimize()
Call to the C++ optimizer on all models of the collection
Usage
PLNPCAfamily$optimize(config)
Arguments
config
list controlling the optimization.
Method getModel()
Extract model from collection and add "PCA" class for compatibility with factoextra::fviz()
Usage
PLNPCAfamily$getModel(var, index = NULL)
Arguments
var
value of the parameter (rank for PLNPCA, sparsity for PLNnetwork) that identifies the model to be extracted from the collection. If no exact match is found, the model with closest parameter value is returned with a warning.
index
Integer index of the model to be returned. Only the first value is taken into account.
Returns
a PLNPCAfit
object
Method getBestModel()
Extract best model in the collection
Usage
PLNPCAfamily$getBestModel(crit = c("ICL", "BIC"))
Arguments
crit
a character for the criterion used to performed the selection. Either "ICL", "BIC". Default is
ICL
Returns
a PLNPCAfit
object
Method plot()
Lineplot of selected criteria for all models in the collection
Usage
PLNPCAfamily$plot(criteria = c("loglik", "BIC", "ICL"), reverse = FALSE)
Arguments
criteria
A valid model selection criteria for the collection of models. Any of "loglik", "BIC" or "ICL" (all).
reverse
A logical indicating whether to plot the value of the criteria in the "natural" direction (loglik - penalty) or in the "reverse" direction (-2 loglik + penalty). Default to FALSE, i.e use the natural direction, on the same scale as the log-likelihood.
Returns
A ggplot2::ggplot
object
Method show()
User friendly print method
Usage
PLNPCAfamily$show()
Method clone()
The objects of this class are cloneable with this method.
Usage
PLNPCAfamily$clone(deep = FALSE)
Arguments
deep
Whether to make a deep clone.
See Also
The function PLNPCA()
, the class PLNPCAfit()
Examples
data(trichoptera)
trichoptera <- prepare_data(trichoptera$Abundance, trichoptera$Covariate)
myPCAs <- PLNPCA(Abundance ~ 1 + offset(log(Offset)), data = trichoptera, ranks = 1:5)
class(myPCAs)
An R6 Class to represent a PLNfit in a PCA framework
Description
The function PLNPCA()
produces a collection of models which are instances of object with class PLNPCAfit
.
This class comes with a set of methods, some of them being useful for the user:
See the documentation for the methods inherited by PLNfit
and the plot()
methods for PCA visualization
Super class
PLNmodels::PLNfit
-> PLNPCAfit
Active bindings
rank
the dimension of the current model
vcov_model
character: the model used for the residual covariance
nb_param
number of parameters in the current PLN model
entropy
entropy of the variational distribution
latent_pos
a matrix: values of the latent position vector (Z) without covariates effects or offset
model_par
a list with the matrices associated with the estimated parameters of the pPCA model: B (covariates), Sigma (covariance), Omega (precision) and C (loadings)
percent_var
the percent of variance explained by each axis
corr_circle
a matrix of correlations to plot the correlation circles
scores
a matrix of scores to plot the individual factor maps (a.k.a. principal components)
rotation
a matrix of rotation of the latent space
eig
description of the eigenvalues, similar to percent_var but for use with external methods
var
a list of data frames with PCA results for the variables:
coord
(coordinates of the variables),cor
(correlation between variables and dimensions),cos2
(Cosine of the variables) andcontrib
(contributions of the variable to the axes)ind
a list of data frames with PCA results for the individuals:
coord
(coordinates of the individuals),cos2
(Cosine of the individuals),contrib
(contributions of individuals to an axis inertia) anddist
(distance of individuals to the origin).call
Hacky binding for compatibility with factoextra functions
Methods
Public methods
Inherited methods
Method new()
Initialize a PLNPCAfit
object
Usage
PLNPCAfit$new(rank, responses, covariates, offsets, weights, formula, control)
Arguments
rank
rank of the PCA (or equivalently, dimension of the latent space)
responses
the matrix of responses (called Y in the model). Will usually be extracted from the corresponding field in
PLNfamily
covariates
design matrix (called X in the model). Will usually be extracted from the corresponding field in
PLNfamily
offsets
offset matrix (called O in the model). Will usually be extracted from the corresponding field in
PLNfamily
weights
an optional vector of observation weights to be used in the fitting process.
formula
model formula used for fitting, extracted from the formula in the upper-level call
control
a list for controlling the optimization. See details.
Method update()
Update a PLNPCAfit
object
Usage
PLNPCAfit$update( B = NA, Sigma = NA, Omega = NA, C = NA, M = NA, S = NA, Z = NA, A = NA, Ji = NA, R2 = NA, monitoring = NA )
Arguments
B
matrix of regression matrix
Sigma
variance-covariance matrix of the latent variables
Omega
precision matrix of the latent variables. Inverse of Sigma.
C
matrix of PCA loadings (in the latent space)
M
matrix of mean vectors for the variational approximation
S
matrix of variance vectors for the variational approximation
Z
matrix of latent vectors (includes covariates and offset effects)
A
matrix of fitted values
Ji
vector of variational lower bounds of the log-likelihoods (one value per sample)
R2
approximate R^2 goodness-of-fit criterion
monitoring
a list with optimization monitoring quantities
Returns
Update the current PLNPCAfit
object
Method optimize()
Call to the C++ optimizer and update of the relevant fields
Usage
PLNPCAfit$optimize(responses, covariates, offsets, weights, config)
Arguments
responses
the matrix of responses (called Y in the model). Will usually be extracted from the corresponding field in
PLNfamily
covariates
design matrix (called X in the model). Will usually be extracted from the corresponding field in
PLNfamily
offsets
offset matrix (called O in the model). Will usually be extracted from the corresponding field in
PLNfamily
weights
an optional vector of observation weights to be used in the fitting process.
config
part of the
control
argument which configures the optimizer
Method optimize_vestep()
Result of one call to the VE step of the optimization procedure: optimal variational parameters (M, S) and corresponding log likelihood values for fixed model parameters (C, B). Intended to position new data in the latent space for further use with PCA.
Usage
PLNPCAfit$optimize_vestep( covariates, offsets, responses, weights = rep(1, self$n), control = PLNPCA_param(backend = "nlopt") )
Arguments
covariates
design matrix (called X in the model). Will usually be extracted from the corresponding field in
PLNfamily
offsets
offset matrix (called O in the model). Will usually be extracted from the corresponding field in
PLNfamily
responses
the matrix of responses (called Y in the model). Will usually be extracted from the corresponding field in
PLNfamily
weights
an optional vector of observation weights to be used in the fitting process.
control
a list for controlling the optimization. See details.
Returns
A list with three components:
the matrix
M
of variational means,the matrix
S2
of variational variancesthe vector
log.lik
of (variational) log-likelihood of each new observation
Method project()
Project new samples into the PCA space using one VE step
Usage
PLNPCAfit$project(newdata, control = PLNPCA_param(), envir = parent.frame())
Arguments
newdata
A data frame in which to look for variables, offsets and counts with which to predict.
control
a list for controlling the optimization. See
PLN()
for details.envir
Environment in which the projection is evaluated
Returns
the named matrix of scores for the newdata, expressed in the same coordinate system as
self$scores
Method setVisualization()
Compute PCA scores in the latent space and update corresponding fields.
Usage
PLNPCAfit$setVisualization(scale.unit = FALSE)
Arguments
scale.unit
Logical. Should PCA scores be rescaled to have unit variance
Method postTreatment()
Update R2, fisher, std_err fields and set up visualization
Usage
PLNPCAfit$postTreatment( responses, covariates, offsets, weights, config_post, config_optim, nullModel )
Arguments
responses
the matrix of responses (called Y in the model). Will usually be extracted from the corresponding field in
PLNfamily
covariates
design matrix (called X in the model). Will usually be extracted from the corresponding field in
PLNfamily
offsets
offset matrix (called O in the model). Will usually be extracted from the corresponding field in
PLNfamily
weights
an optional vector of observation weights to be used in the fitting process.
config_post
a list for controlling the post-treatments (optional bootstrap, jackknife, R2, etc.). See details
config_optim
a list for controlling the optimizer (either "nlopt" or "torch" backend). See details
nullModel
null model used for approximate R2 computations. Defaults to a GLM model with same design matrix but not latent variable.
Details
The list of parameters config_post
controls the post-treatment processing, with the following entries:
jackknife boolean indicating whether jackknife should be performed to evaluate bias and variance of the model parameters. Default is FALSE.
bootstrap integer indicating the number of bootstrap resamples generated to evaluate the variance of the model parameters. Default is 0 (inactivated).
variational_var boolean indicating whether variational Fisher information matrix should be computed to estimate the variance of the model parameters (highly underestimated). Default is FALSE.
rsquared boolean indicating whether approximation of R2 based on deviance should be computed. Default is TRUE
trace integer for verbosity. should be > 1 to see output in post-treatments
Method plot_individual_map()
Plot the factorial map of the PCA
Usage
PLNPCAfit$plot_individual_map( axes = 1:min(2, self$rank), main = "Individual Factor Map", plot = TRUE, cols = "default" )
Arguments
axes
numeric, the axes to use for the plot when map = "individual" or "variable". Default it c(1,min(rank))
main
character. A title for the single plot (individual or variable factor map). If NULL (the default), an hopefully appropriate title will be used.
plot
logical. Should the plot be displayed or sent back as ggplot object
cols
a character, factor or numeric to define the color associated with the individuals. By default, all individuals receive the default color of the current palette.
Returns
a ggplot2::ggplot
graphic
Method plot_correlation_circle()
Plot the correlation circle of a specified axis for a PLNLDAfit
object
Usage
PLNPCAfit$plot_correlation_circle( axes = 1:min(2, self$rank), main = "Variable Factor Map", cols = "default", plot = TRUE )
Arguments
axes
numeric, the axes to use for the plot when map = "individual" or "variable". Default it c(1,min(rank))
main
character. A title for the single plot (individual or variable factor map). If NULL (the default), an hopefully appropriate title will be used.
cols
a character, factor or numeric to define the color associated with the variables. By default, all variables receive the default color of the current palette.
plot
logical. Should the plot be displayed or sent back as ggplot object
Returns
a ggplot2::ggplot
graphic
Method plot_PCA()
Plot a summary of the PLNPCAfit
object
Usage
PLNPCAfit$plot_PCA( nb_axes = min(3, self$rank), ind_cols = "ind_cols", var_cols = "var_cols", plot = TRUE )
Arguments
nb_axes
scalar: the number of axes to be considered when map = "both". The default is min(3,rank).
ind_cols
a character, factor or numeric to define the color associated with the individuals. By default, all variables receive the default color of the current palette.
var_cols
a character, factor or numeric to define the color associated with the variables. By default, all variables receive the default color of the current palette.
plot
logical. Should the plot be displayed or sent back as ggplot object
Returns
a grob
object
Method show()
User friendly print method
Usage
PLNPCAfit$show()
Method clone()
The objects of this class are cloneable with this method.
Usage
PLNPCAfit$clone(deep = FALSE)
Arguments
deep
Whether to make a deep clone.
See Also
The function PLNPCA
, the class PLNPCAfamily
Examples
data(trichoptera)
trichoptera <- prepare_data(trichoptera$Abundance, trichoptera$Covariate)
myPCAs <- PLNPCA(Abundance ~ 1 + offset(log(Offset)), data = trichoptera, ranks = 1:5)
myPCA <- getBestModel(myPCAs)
class(myPCA)
print(myPCA)
Control of a PLN fit
Description
Helper to define list of parameters to control the PLN fit. All arguments have defaults.
Usage
PLN_param(
backend = c("nlopt", "torch"),
trace = 1,
covariance = c("full", "diagonal", "spherical", "fixed"),
Omega = NULL,
config_post = list(),
config_optim = list(),
inception = NULL
)
Arguments
backend |
optimization back used, either "nlopt" or "torch". Default is "nlopt" |
trace |
a integer for verbosity. |
covariance |
character setting the model for the covariance matrix. Either "full", "diagonal", "spherical" or "fixed". Default is "full". |
Omega |
precision matrix of the latent variables. Inverse of Sigma. Must be specified if |
config_post |
a list for controlling the post-treatments (optional bootstrap, jackknife, R2, etc.). See details |
config_optim |
a list for controlling the optimizer (either "nlopt" or "torch" backend). See details |
inception |
Set up the parameters initialization: by default, the model is initialized with a multivariate linear model applied on log-transformed data, and with the same formula as the one provided by the user. However, the user can provide a PLNfit (typically obtained from a previous fit), which sometimes speeds up the inference. |
Details
The list of parameters config_optim
controls the optimizers. When "nlopt" is chosen the following entries are relevant
"algorithm" the optimization method used by NLOPT among LD type, e.g. "CCSAQ", "MMA", "LBFGS". See NLOPT documentation for further details. Default is "CCSAQ".
"maxeval" stop when the number of iteration exceeds maxeval. Default is 10000
"ftol_rel" stop when an optimization step changes the objective function by less than ftol multiplied by the absolute value of the parameter. Default is 1e-8
"xtol_rel" stop when an optimization step changes every parameters by less than xtol multiplied by the absolute value of the parameter. Default is 1e-6
"ftol_abs" stop when an optimization step changes the objective function by less than ftol_abs. Default is 0.0 (disabled)
"xtol_abs" stop when an optimization step changes every parameters by less than xtol_abs. Default is 0.0 (disabled)
"maxtime" stop when the optimization time (in seconds) exceeds maxtime. Default is -1 (disabled)
When "torch" backend is used (only for PLN and PLNLDA for now), the following entries are relevant:
"algorithm" the optimizer used by torch among RPROP (default), RMSPROP, ADAM and ADAGRAD
"maxeval" stop when the number of iteration exceeds maxeval. Default is 10 000
"numepoch" stop training once this number of epochs exceeds numepoch. Set to -1 to enable infinite training. Default is 1 000
"num_batch" number of batches to use during training. Defaults to 1 (use full dataset at each epoch)
"ftol_rel" stop when an optimization step changes the objective function by less than ftol multiplied by the absolute value of the parameter. Default is 1e-8
"xtol_rel" stop when an optimization step changes every parameters by less than xtol multiplied by the absolute value of the parameter. Default is 1e-6
"lr" learning rate. Default is 0.1.
"momentum" momentum factor. Default is 0 (no momentum). Only used in RMSPROP
"weight_decay" Weight decay penalty. Default is 0 (no decay). Not used in RPROP
"step_sizes" pair of minimal (default: 1e-6) and maximal (default: 50) allowed step sizes. Only used in RPROP
"etas" pair of multiplicative increase and decrease factors. Default is (0.5, 1.2). Only used in RPROP
"centered" if TRUE, compute the centered RMSProp where the gradient is normalized by an estimation of its variance weight_decay (L2 penalty). Default to FALSE. Only used in RMSPROP
The list of parameters config_post
controls the post-treatment processing (for most PLN*()
functions), with the following entries (defaults may vary depending on the specific function, check config_post_default_*
for defaults values):
jackknife boolean indicating whether jackknife should be performed to evaluate bias and variance of the model parameters. Default is FALSE.
bootstrap integer indicating the number of bootstrap resamples generated to evaluate the variance of the model parameters. Default is 0 (inactivated).
variational_var boolean indicating whether variational Fisher information matrix should be computed to estimate the variance of the model parameters (highly underestimated). Default is FALSE.
sandwich_var boolean indicating whether sandwich estimation should be used to estimate the variance of the model parameters (highly underestimated). Default is FALSE.
rsquared boolean indicating whether approximation of R2 based on deviance should be computed. Default is TRUE
Value
list of parameters configuring the fit.
An R6 Class to represent a collection of PLNfit
Description
super class for PLNPCAfamily
and PLNnetworkfamily
.
Public fields
responses
the matrix of responses common to every models
covariates
the matrix of covariates common to every models
offsets
the matrix of offsets common to every models
weights
the vector of observation weights
inception
a PLNfit object, obtained when no sparsifying penalty is applied.
models
a list of PLNfit object, one per penalty.
Active bindings
criteria
a data frame with the values of some criteria (approximated log-likelihood, BIC, ICL, etc.) for the collection of models / fits BIC and ICL are defined so that they are on the same scale as the model log-likelihood, i.e. with the form, loglik - 0.5 penalty
convergence
sends back a data frame with some convergence diagnostics associated with the optimization process (method, optimal value, etc)
Methods
Public methods
Method new()
Create a new PLNfamily
object.
Usage
PLNfamily$new(responses, covariates, offsets, weights, control)
Arguments
responses
the matrix of responses common to every models
covariates
the matrix of covariates common to every models
offsets
the matrix of offsets common to every models
weights
the vector of observation weights
control
list controlling the optimization and the model
Returns
A new PLNfamily
object
Method postTreatment()
Update fields after optimization
Usage
PLNfamily$postTreatment(config_post, config_optim)
Arguments
config_post
a list for controlling the post-treatments (optional bootstrap, jackknife, R2, etc.).
config_optim
a list for controlling the optimization parameters used during post_treatments
Method getModel()
Extract a model from a collection of models
Usage
PLNfamily$getModel(var, index = NULL)
Arguments
var
value of the parameter (
rank
for PLNPCA,sparsity
for PLNnetwork) that identifies the model to be extracted from the collection. If no exact match is found, the model with closest parameter value is returned with a warning.index
Integer index of the model to be returned. Only the first value is taken into account.
Returns
A PLNfit
object
Method plot()
Lineplot of selected criteria for all models in the collection
Usage
PLNfamily$plot(criteria, reverse)
Arguments
criteria
A valid model selection criteria for the collection of models. Includes loglik, BIC (all), ICL (PLNPCA) and pen_loglik, EBIC (PLNnetwork)
reverse
A logical indicating whether to plot the value of the criteria in the "natural" direction (loglik - penalty) or in the "reverse" direction (-2 loglik + penalty). Default to FALSE, i.e use the natural direction, on the same scale as the log-likelihood.
Returns
A ggplot2::ggplot
object
Method show()
User friendly print method
Usage
PLNfamily$show()
Method print()
User friendly print method
Usage
PLNfamily$print()
Method clone()
The objects of this class are cloneable with this method.
Usage
PLNfamily$clone(deep = FALSE)
Arguments
deep
Whether to make a deep clone.
See Also
An R6 Class to represent a PLNfit in a standard, general framework
Description
The function PLN()
fit a model which is an instance of a object with class PLNfit
.
Objects produced by the functions PLNnetwork()
, PLNPCA()
, PLNmixture()
and PLNLDA()
also enjoy the methods of PLNfit()
by inheritance.
This class comes with a set of R6 methods, some of them being useful for the user and exported as S3 methods.
See the documentation for coef()
, sigma()
, predict()
, vcov()
and standard_error()
.
Fields are accessed via active binding and cannot be changed by the user.
Active bindings
n
number of samples
q
number of dimensions of the latent space
p
number of species
d
number of covariates
nb_param
number of parameters in the current PLN model
model_par
a list with the matrices of the model parameters: B (covariates), Sigma (covariance), Omega (precision matrix), plus some others depending on the variant)
var_par
a list with the matrices of the variational parameters: M (means) and S2 (variances)
optim_par
a list with parameters useful for monitoring the optimization
latent
a matrix: values of the latent vector (Z in the model)
latent_pos
a matrix: values of the latent position vector (Z) without covariates effects or offset
fitted
a matrix: fitted values of the observations (A in the model)
vcov_coef
matrix of sandwich estimator of the variance-covariance of B (need fixed -ie known- covariance at the moment)
vcov_model
character: the model used for the residual covariance
weights
observational weights
loglik
(weighted) variational lower bound of the loglikelihood
loglik_vec
element-wise variational lower bound of the loglikelihood
BIC
variational lower bound of the BIC
entropy
Entropy of the variational distribution
ICL
variational lower bound of the ICL
R_squared
approximated goodness-of-fit criterion
criteria
a vector with loglik, BIC, ICL and number of parameters
Methods
Public methods
Method new()
Initialize a PLNfit
model
Usage
PLNfit$new(responses, covariates, offsets, weights, formula, control)
Arguments
responses
the matrix of responses (called Y in the model). Will usually be extracted from the corresponding field in PLNfamily-class
covariates
design matrix (called X in the model). Will usually be extracted from the corresponding field in PLNfamily-class
offsets
offset matrix (called O in the model). Will usually be extracted from the corresponding field in PLNfamily-class
weights
an optional vector of observation weights to be used in the fitting process.
formula
model formula used for fitting, extracted from the formula in the upper-level call
control
a list-like structure for controlling the fit, see
PLN_param()
.
Method update()
Update a PLNfit
object
Usage
PLNfit$update( B = NA, Sigma = NA, Omega = NA, M = NA, S = NA, Ji = NA, R2 = NA, Z = NA, A = NA, monitoring = NA )
Arguments
B
matrix of regression matrix
Sigma
variance-covariance matrix of the latent variables
Omega
precision matrix of the latent variables. Inverse of Sigma.
M
matrix of variational parameters for the mean
S
matrix of variational parameters for the variance
Ji
vector of variational lower bounds of the log-likelihoods (one value per sample)
R2
approximate R^2 goodness-of-fit criterion
Z
matrix of latent vectors (includes covariates and offset effects)
A
matrix of fitted values
monitoring
a list with optimization monitoring quantities
Returns
Update the current PLNfit
object
Method optimize()
Call to the NLopt or TORCH optimizer and update of the relevant fields
Usage
PLNfit$optimize(responses, covariates, offsets, weights, config)
Arguments
responses
the matrix of responses (called Y in the model). Will usually be extracted from the corresponding field in PLNfamily-class
covariates
design matrix (called X in the model). Will usually be extracted from the corresponding field in PLNfamily-class
offsets
offset matrix (called O in the model). Will usually be extracted from the corresponding field in PLNfamily-class
weights
an optional vector of observation weights to be used in the fitting process.
config
part of the
control
argument which configures the optimizer
Method optimize_vestep()
Result of one call to the VE step of the optimization procedure: optimal variational parameters (M, S) and corresponding log likelihood values for fixed model parameters (Sigma, B). Intended to position new data in the latent space.
Usage
PLNfit$optimize_vestep( covariates, offsets, responses, weights, B = self$model_par$B, Omega = self$model_par$Omega, control = PLN_param(backend = "nlopt") )
Arguments
covariates
design matrix (called X in the model). Will usually be extracted from the corresponding field in PLNfamily-class
offsets
offset matrix (called O in the model). Will usually be extracted from the corresponding field in PLNfamily-class
responses
the matrix of responses (called Y in the model). Will usually be extracted from the corresponding field in PLNfamily-class
weights
an optional vector of observation weights to be used in the fitting process.
B
Optional fixed value of the regression parameters
Omega
precision matrix of the latent variables. Inverse of Sigma.
control
a list-like structure for controlling the fit, see
PLN_param()
.Sigma
variance-covariance matrix of the latent variables
Returns
A list with three components:
the matrix
M
of variational means,the matrix
S2
of variational variancesthe vector
log.lik
of (variational) log-likelihood of each new observation
Method postTreatment()
Update R2, fisher and std_err fields after optimization
Usage
PLNfit$postTreatment( responses, covariates, offsets, weights = rep(1, nrow(responses)), config_post, config_optim, nullModel = NULL )
Arguments
responses
the matrix of responses (called Y in the model). Will usually be extracted from the corresponding field in PLNfamily-class
covariates
design matrix (called X in the model). Will usually be extracted from the corresponding field in PLNfamily-class
offsets
offset matrix (called O in the model). Will usually be extracted from the corresponding field in PLNfamily-class
weights
an optional vector of observation weights to be used in the fitting process.
config_post
a list for controlling the post-treatments (optional bootstrap, jackknife, R2, etc.). See details
config_optim
a list for controlling the optimization (optional bootstrap, jackknife, R2, etc.). See details
nullModel
null model used for approximate R2 computations. Defaults to a GLM model with same design matrix but not latent variable.
Details
The list of parameters config
controls the post-treatment processing, with the following entries:
jackknife boolean indicating whether jackknife should be performed to evaluate bias and variance of the model parameters. Default is FALSE.
bootstrap integer indicating the number of bootstrap resamples generated to evaluate the variance of the model parameters. Default is 0 (inactivated).
variational_var boolean indicating whether variational Fisher information matrix should be computed to estimate the variance of the model parameters (highly underestimated). Default is FALSE.
sandwich_var boolean indicating whether sandwich estimator should be computed to estimate the variance of the model parameters (highly underestimated). Default is FALSE.
trace integer for verbosity. should be > 1 to see output in post-treatments
Method predict()
Predict position, scores or observations of new data.
Usage
PLNfit$predict( newdata, responses = NULL, type = c("link", "response"), level = 1, envir = parent.frame() )
Arguments
newdata
A data frame in which to look for variables with which to predict. If omitted, the fitted values are used.
responses
Optional data frame containing the count of the observed variables (matching the names of the provided as data in the PLN function), assuming the interest in in testing the model.
type
Scale used for the prediction. Either
link
(default, predicted positions in the latent space) orresponse
(predicted counts).level
Optional integer value the level to be used in obtaining the predictions. Level zero corresponds to the population predictions (default if
responses
is not provided) while level one (default) corresponds to predictions after evaluating the variational parameters for the new data.envir
Environment in which the prediction is evaluated
Details
Note that level = 1
can only be used if responses are provided,
as the variational parameters can't be estimated otherwise. In the absence of responses, level
is ignored and the fitted values are returned
Returns
A matrix with predictions scores or counts.
Method predict_cond()
Predict position, scores or observations of new data, conditionally on the observation of a (set of) variables
Usage
PLNfit$predict_cond( newdata, cond_responses, type = c("link", "response"), var_par = FALSE, envir = parent.frame() )
Arguments
newdata
a data frame containing the covariates of the sites where to predict
cond_responses
a data frame containing the count of the observed variables (matching the names of the provided as data in the PLN function)
type
Scale used for the prediction. Either
link
(default, predicted positions in the latent space) orresponse
(predicted counts).var_par
Boolean. Should new estimations of the variational parameters of mean and variance be sent back, as attributes of the matrix of predictions. Default to
FALSE
.envir
Environment in which the prediction is evaluated
Returns
A matrix with predictions scores or counts.
Method show()
User friendly print method
Usage
PLNfit$show( model = paste("A multivariate Poisson Lognormal fit with", self$vcov_model, "covariance model.\n") )
Arguments
model
First line of the print output
Method print()
User friendly print method
Usage
PLNfit$print()
Method clone()
The objects of this class are cloneable with this method.
Usage
PLNfit$clone(deep = FALSE)
Arguments
deep
Whether to make a deep clone.
Examples
## Not run:
data(trichoptera)
trichoptera <- prepare_data(trichoptera$Abundance, trichoptera$Covariate)
myPLN <- PLN(Abundance ~ 1, data = trichoptera)
class(myPLN)
print(myPLN)
## End(Not run)
An R6 Class to represent a PLNfit in a standard, general framework, with diagonal residual covariance
Description
The function PLNLDA()
produces an instance of an object with class PLNLDAfit
.
This class comes with a set of methods, some of them being useful for the user:
See the documentation for the methods inherited by PLNfit()
, the plot()
method for
LDA visualization and predict()
method for prediction
Super class
PLNmodels::PLNfit
-> PLNfit_diagonal
Active bindings
nb_param
number of parameters in the current PLN model
vcov_model
character: the model used for the residual covariance
Methods
Public methods
Inherited methods
Method new()
Initialize a PLNfit
model
Usage
PLNfit_diagonal$new(responses, covariates, offsets, weights, formula, control)
Arguments
responses
the matrix of responses (called Y in the model). Will usually be extracted from the corresponding field in PLNfamily-class
covariates
design matrix (called X in the model). Will usually be extracted from the corresponding field in PLNfamily-class
offsets
offset matrix (called O in the model). Will usually be extracted from the corresponding field in PLNfamily-class
weights
an optional vector of observation weights to be used in the fitting process.
formula
model formula used for fitting, extracted from the formula in the upper-level call
control
a list for controlling the optimization. See details.
Method clone()
The objects of this class are cloneable with this method.
Usage
PLNfit_diagonal$clone(deep = FALSE)
Arguments
deep
Whether to make a deep clone.
Super classes
PLNmodels::PLNfit
-> PLNmodels::PLNLDAfit
-> PLNLDAfit_spherical
Active bindings
vcov_model
character: the model used for the residual covariance
nb_param
number of parameters in the current PLN model
Methods
Public methods
Inherited methods
PLNmodels::PLNfit$optimize_vestep()
PLNmodels::PLNfit$predict_cond()
PLNmodels::PLNfit$print()
PLNmodels::PLNfit$update()
PLNmodels::PLNLDAfit$optimize()
PLNmodels::PLNLDAfit$plot_LDA()
PLNmodels::PLNLDAfit$plot_correlation_map()
PLNmodels::PLNLDAfit$plot_individual_map()
PLNmodels::PLNLDAfit$postTreatment()
PLNmodels::PLNLDAfit$predict()
PLNmodels::PLNLDAfit$setVisualization()
PLNmodels::PLNLDAfit$show()
Method new()
Initialize a PLNfit
model
Usage
PLNLDAfit_spherical$new( grouping, responses, covariates, offsets, weights, formula, control )
Arguments
grouping
a factor specifying the class of each observation used for discriminant analysis.
responses
the matrix of responses (called Y in the model). Will usually be extracted from the corresponding field in PLNfamily-class
covariates
design matrix (called X in the model). Will usually be extracted from the corresponding field in PLNfamily-class
offsets
offset matrix (called O in the model). Will usually be extracted from the corresponding field in PLNfamily-class
weights
an optional vector of observation weights to be used in the fitting process.
formula
model formula used for fitting, extracted from the formula in the upper-level call
control
a list for controlling the optimization. See details.
Method clone()
The objects of this class are cloneable with this method.
Usage
PLNLDAfit_spherical$clone(deep = FALSE)
Arguments
deep
Whether to make a deep clone.
Examples
## Not run:
data(trichoptera)
trichoptera <- prepare_data(trichoptera$Abundance, trichoptera$Covariate)
myPLN <- PLN(Abundance ~ 1, data = trichoptera)
class(myPLN)
print(myPLN)
## End(Not run)
## Not run:
data(trichoptera)
trichoptera <- prepare_data(trichoptera$Abundance, trichoptera$Covariate)
myPLNLDA <- PLNLDA(Abundance ~ 1, data = trichoptera, control = PLN_param(covariance = "spherical"))
class(myPLNLDA)
print(myPLNLDA)
## End(Not run)
An R6 Class to represent a PLNfit in a standard, general framework, with fixed (inverse) residual covariance
Description
An R6 Class to represent a PLNfit in a standard, general framework, with fixed (inverse) residual covariance
An R6 Class to represent a PLNfit in a standard, general framework, with fixed (inverse) residual covariance
Super class
PLNmodels::PLNfit
-> PLNfit_fixedcov
Active bindings
nb_param
number of parameters in the current PLN model
vcov_model
character: the model used for the residual covariance
vcov_coef
matrix of sandwich estimator of the variance-covariance of B (needs known covariance at the moment)
Methods
Public methods
Inherited methods
Method new()
Initialize a PLNfit
model
Usage
PLNfit_fixedcov$new(responses, covariates, offsets, weights, formula, control)
Arguments
responses
the matrix of responses (called Y in the model). Will usually be extracted from the corresponding field in PLNfamily-class
covariates
design matrix (called X in the model). Will usually be extracted from the corresponding field in PLNfamily-class
offsets
offset matrix (called O in the model). Will usually be extracted from the corresponding field in PLNfamily-class
weights
an optional vector of observation weights to be used in the fitting process.
formula
model formula used for fitting, extracted from the formula in the upper-level call
control
a list for controlling the optimization. See details.
Method optimize()
Call to the NLopt or TORCH optimizer and update of the relevant fields
Usage
PLNfit_fixedcov$optimize(responses, covariates, offsets, weights, config)
Arguments
responses
the matrix of responses (called Y in the model). Will usually be extracted from the corresponding field in PLNfamily-class
covariates
design matrix (called X in the model). Will usually be extracted from the corresponding field in PLNfamily-class
offsets
offset matrix (called O in the model). Will usually be extracted from the corresponding field in PLNfamily-class
weights
an optional vector of observation weights to be used in the fitting process.
config
part of the
control
argument which configures the optimizer
Method clone()
The objects of this class are cloneable with this method.
Usage
PLNfit_fixedcov$clone(deep = FALSE)
Arguments
deep
Whether to make a deep clone.
Examples
## Not run:
data(trichoptera)
trichoptera <- prepare_data(trichoptera$Abundance, trichoptera$Covariate)
myPLN <- PLN(Abundance ~ 1, data = trichoptera)
class(myPLN)
print(myPLN)
## End(Not run)
An R6 Class to represent a PLNfit in a standard, general framework, with spherical residual covariance
Description
An R6 Class to represent a PLNfit in a standard, general framework, with spherical residual covariance
An R6 Class to represent a PLNfit in a standard, general framework, with spherical residual covariance
Super class
PLNmodels::PLNfit
-> PLNfit_spherical
Active bindings
nb_param
number of parameters in the current PLN model
vcov_model
character: the model used for the residual covariance
Methods
Public methods
Inherited methods
Method new()
Initialize a PLNfit
model
Usage
PLNfit_spherical$new(responses, covariates, offsets, weights, formula, control)
Arguments
responses
the matrix of responses (called Y in the model). Will usually be extracted from the corresponding field in PLNfamily-class
covariates
design matrix (called X in the model). Will usually be extracted from the corresponding field in PLNfamily-class
offsets
offset matrix (called O in the model). Will usually be extracted from the corresponding field in PLNfamily-class
weights
an optional vector of observation weights to be used in the fitting process.
formula
model formula used for fitting, extracted from the formula in the upper-level call
control
a list for controlling the optimization. See details.
Method clone()
The objects of this class are cloneable with this method.
Usage
PLNfit_spherical$clone(deep = FALSE)
Arguments
deep
Whether to make a deep clone.
Examples
## Not run:
data(trichoptera)
trichoptera <- prepare_data(trichoptera$Abundance, trichoptera$Covariate)
myPLN <- PLN(Abundance ~ 1, data = trichoptera)
class(myPLN)
print(myPLN)
## End(Not run)
Poisson lognormal mixture model
Description
Fit the mixture variants of the Poisson lognormal with a variational algorithm. Use the (g)lm syntax for model specification (covariates, offsets).
Usage
PLNmixture(formula, data, subset, clusters = 1:5, control = PLNmixture_param())
Arguments
formula |
an object of class "formula": a symbolic description of the model to be fitted. |
data |
an optional data frame, list or environment (or object coercible by as.data.frame to a data frame) containing the variables in the model. If not found in data, the variables are taken from environment(formula), typically the environment from which lm is called. |
subset |
an optional vector specifying a subset of observations to be used in the fitting process. |
clusters |
a vector of integer containing the successive number of clusters (or components) to be considered |
control |
a list-like structure for controlling the optimization, with default generated by |
Value
an R6 object with class PLNmixturefamily
, which contains
a collection of models with class PLNmixturefit
See Also
The classes PLNmixturefamily
, PLNmixturefit
and PLNmixture_param()
Examples
## Use future to dispatch the computations on 2 workers
## Not run:
future::plan("multisession", workers = 2)
## End(Not run)
data(trichoptera)
trichoptera <- prepare_data(trichoptera$Abundance, trichoptera$Covariate)
myMixtures <- PLNmixture(Abundance ~ 1 + offset(log(Offset)), clusters = 1:4, data = trichoptera,
control = PLNmixture_param(smoothing = 'none'))
# Shut down parallel workers
## Not run:
future::plan("sequential")
## End(Not run)
Control of a PLNmixture fit
Description
Helper to define list of parameters to control the PLNmixture fit. All arguments have defaults.
Usage
PLNmixture_param(
backend = "nlopt",
trace = 1,
covariance = "spherical",
init_cl = "kmeans",
smoothing = "both",
config_optim = list(),
config_post = list(),
inception = NULL
)
Arguments
backend |
optimization back used, either "nlopt" or "torch". Default is "nlopt" |
trace |
a integer for verbosity. |
covariance |
character setting the model for the covariance matrices of the mixture components. Either "full", "diagonal" or "spherical". Default is "spherical". |
init_cl |
The initial clustering to apply. Either, 'kmeans', CAH' or a user defined clustering given as a list of clusterings, the size of which is equal to the number of clusters considered. Default is 'kmeans'. |
smoothing |
The smoothing to apply. Either, 'none', forward', 'backward' or 'both'. Default is 'both'. |
config_optim |
a list for controlling the optimizer (either "nlopt" or "torch" backend). See details |
config_post |
a list for controlling the post-treatments (optional bootstrap, jackknife, R2, etc.). |
inception |
Set up the parameters initialization: by default, the model is initialized with a multivariate linear model applied on log-transformed data, and with the same formula as the one provided by the user. However, the user can provide a PLNfit (typically obtained from a previous fit), which sometimes speeds up the inference. |
Details
See PLN_param()
for a full description of the generic optimization parameters. PLNmixture_param() also has additional parameters controlling the optimization due the inner-outer loop structure of the optimizer:
"ftol_out" outer solver stops when an optimization step changes the objective function by less than xtol multiplied by the absolute value of the parameter. Default is 1e-6
"maxit_out" outer solver stops when the number of iteration exceeds maxit_out. Default is 50
"it_smoothing" number of the iterations of the smoothing procedure. Default is 1.
Value
list of parameters configuring the fit.
See Also
An R6 Class to represent a collection of PLNmixturefit
Description
The function PLNmixture()
produces an instance of this class.
This class comes with a set of methods, some of them being useful for the user:
See the documentation for getBestModel()
, getModel()
and plot()
.
Super class
PLNmodels::PLNfamily
-> PLNmixturefamily
Active bindings
clusters
vector indicating the number of clusters considered is the successively fitted models
Methods
Public methods
Inherited methods
Method new()
helper function for forward smoothing: split a group
Initialize all models in the collection.
Usage
PLNmixturefamily$new( clusters, responses, covariates, offsets, formula, control )
Arguments
clusters
the dimensions of the successively fitted models
responses
the matrix of responses common to every models
covariates
the matrix of covariates common to every models
offsets
the matrix of offsets common to every models
formula
model formula used for fitting, extracted from the formula in the upper-level call
control
a list for controlling the optimization. See details.
control
a list for controlling the optimization. See details.
Method optimize()
Call to the optimizer on all models of the collection
Usage
PLNmixturefamily$optimize(config)
Arguments
config
a list for controlling the optimization
Method smooth()
function to restart clustering to avoid local minima by smoothing the loglikelihood values as a function of the number of clusters
Usage
PLNmixturefamily$smooth(control)
Arguments
control
a list to control the smoothing process
Method plot()
Lineplot of selected criteria for all models in the collection
Usage
PLNmixturefamily$plot(criteria = c("loglik", "BIC", "ICL"), reverse = FALSE)
Arguments
criteria
A valid model selection criteria for the collection of models. Any of "loglik", "BIC" or "ICL" (all).
reverse
A logical indicating whether to plot the value of the criteria in the "natural" direction (loglik - 0.5 penalty) or in the "reverse" direction (-2 loglik + penalty). Default to FALSE, i.e use the natural direction, on the same scale as the log-likelihood..
Returns
A ggplot2::ggplot
object
Method plot_objective()
Plot objective value of the optimization problem along the penalty path
Usage
PLNmixturefamily$plot_objective()
Returns
a ggplot2::ggplot
graph
Method getBestModel()
Extract best model in the collection
Usage
PLNmixturefamily$getBestModel(crit = c("BIC", "ICL", "loglik"))
Arguments
crit
a character for the criterion used to performed the selection. Either "BIC", "ICL" or "loglik". Default is
ICL
Returns
a PLNmixturefit
object
Method show()
User friendly print method
Usage
PLNmixturefamily$show()
Method print()
User friendly print method
Usage
PLNmixturefamily$print()
Method clone()
The objects of this class are cloneable with this method.
Usage
PLNmixturefamily$clone(deep = FALSE)
Arguments
deep
Whether to make a deep clone.
See Also
The function PLNmixture
, the class PLNmixturefit
An R6 Class to represent a PLNfit in a mixture framework
Description
The function PLNmixture
produces a collection of models which are instances of object with class PLNmixturefit
.
A PLNmixturefit
(say, with k components) is itself a collection of k PLNfit
.
This class comes with a set of methods, some of them being useful for the user: See the documentation for ...
Active bindings
n
number of samples
p
number of dimensions of the latent space
k
number of components
d
number of covariates
components
components of the mixture (PLNfits)
latent
a matrix: values of the latent vector (Z in the model)
latent_pos
a matrix: values of the latent position vector (Z) without covariates effects or offset
posteriorProb
matrix ofposterior probability for cluster belonging
memberships
vector for cluster index
mixtureParam
vector of cluster proportions
optim_par
a list with parameters useful for monitoring the optimization
nb_param
number of parameters in the current PLN model
entropy_clustering
Entropy of the variational distribution of the cluster (multinomial)
entropy_latent
Entropy of the variational distribution of the latent vector (Gaussian)
entropy
Full entropy of the variational distribution (latent vector + clustering)
loglik
variational lower bound of the loglikelihood
loglik_vec
element-wise variational lower bound of the loglikelihood
BIC
variational lower bound of the BIC
ICL
variational lower bound of the ICL (include entropy of both the clustering and latent distributions)
R_squared
approximated goodness-of-fit criterion
criteria
a vector with loglik, BIC, ICL, and number of parameters
model_par
a list with the matrices of parameters found in the model (Theta, Sigma, Mu and Pi)
vcov_model
character: the model used for the covariance (either "spherical", "diagonal" or "full")
fitted
a matrix: fitted values of the observations (A in the model)
group_means
a matrix of group mean vectors in the latent space.
Methods
Public methods
Method new()
Optimize a the
Initialize a PLNmixturefit
model
Usage
PLNmixturefit$new( responses, covariates, offsets, posteriorProb, formula, control )
Arguments
responses
the matrix of responses common to every models
covariates
the matrix of covariates common to every models
offsets
the matrix of offsets common to every models
posteriorProb
matrix ofposterior probability for cluster belonging
formula
model formula used for fitting, extracted from the formula in the upper-level call
control
a list for controlling the optimization.
Method optimize()
Optimize a PLNmixturefit
model
Usage
PLNmixturefit$optimize(responses, covariates, offsets, config)
Arguments
responses
the matrix of responses common to every models
covariates
the matrix of covariates common to every models
offsets
the matrix of offsets common to every models
config
a list for controlling the optimization
Method predict()
Predict group of new samples
Usage
PLNmixturefit$predict( newdata, type = c("posterior", "response", "position"), prior = matrix(rep(1/self$k, self$k), nrow(newdata), self$k, byrow = TRUE), control = PLNmixture_param(), envir = parent.frame() )
Arguments
newdata
A data frame in which to look for variables, offsets and counts with which to predict.
type
The type of prediction required. The default
posterior
are posterior probabilities for each group ,response
is the group with maximal posterior probability andlatent
is the averaged latent coordinate (without offset and nor covariate effects), with weights equal to the posterior probabilities.prior
User-specified prior group probabilities in the new data. The default uses a uniform prior.
control
a list-like structure for controlling the fit. See
PLNmixture_param()
for details.envir
Environment in which the prediction is evaluated
Method plot_clustering_data()
Plot the matrix of expected mean counts (without offsets, without covariate effects) reordered according the inferred clustering
Usage
PLNmixturefit$plot_clustering_data( main = "Expected counts reorder by clustering", plot = TRUE, log_scale = TRUE )
Arguments
main
character. A title for the plot. An hopefully appropriate title will be used by default.
plot
logical. Should the plot be displayed or sent back as
ggplot2::ggplot
objectlog_scale
logical. Should the color scale values be log-transform before plotting? Default is
TRUE
.
Returns
a ggplot2::ggplot
graphic
Method plot_clustering_pca()
Plot the individual map of a PCA performed on the latent coordinates, where individuals are colored according to the memberships
Usage
PLNmixturefit$plot_clustering_pca( main = "Clustering labels in Individual Factor Map", plot = TRUE )
Arguments
main
character. A title for the plot. An hopefully appropriate title will be used by default.
plot
logical. Should the plot be displayed or sent back as
ggplot2::ggplot
object
Returns
a ggplot2::ggplot
graphic
Method postTreatment()
Update fields after optimization
Usage
PLNmixturefit$postTreatment( responses, covariates, offsets, weights, config_post, config_optim, nullModel )
Arguments
responses
the matrix of responses common to every models
covariates
the matrix of covariates common to every models
offsets
the matrix of offsets common to every models
weights
an optional vector of observation weights to be used in the fitting process.
config_post
a list for controlling the post-treatment
config_optim
a list for controlling the optimization during the post-treatment computations
nullModel
null model used for approximate R2 computations. Defaults to a GLM model with same design matrix but not latent variable.
Method show()
User friendly print method
Usage
PLNmixturefit$show()
Method print()
User friendly print method
Usage
PLNmixturefit$print()
Method clone()
The objects of this class are cloneable with this method.
Usage
PLNmixturefit$clone(deep = FALSE)
Arguments
deep
Whether to make a deep clone.
See Also
The function PLNmixture
, the class PLNmixturefamily
Sparse Poisson lognormal model for network inference
Description
Perform sparse inverse covariance estimation for the Zero Inflated Poisson lognormal model using a variational algorithm. Iterate over a range of logarithmically spaced sparsity parameter values. Use the (g)lm syntax to specify the model (including covariates and offsets).
Usage
PLNnetwork(
formula,
data,
subset,
weights,
penalties = NULL,
control = PLNnetwork_param()
)
Arguments
formula |
an object of class "formula": a symbolic description of the model to be fitted. |
data |
an optional data frame, list or environment (or object coercible by as.data.frame to a data frame) containing the variables in the model. If not found in data, the variables are taken from environment(formula), typically the environment from which lm is called. |
subset |
an optional vector specifying a subset of observations to be used in the fitting process. |
weights |
an optional vector of observation weights to be used in the fitting process. |
penalties |
an optional vector of positive real number controlling the level of sparsity of the underlying network. if NULL (the default), will be set internally. See |
control |
a list-like structure for controlling the optimization, with default generated by |
Value
an R6 object with class PLNnetworkfamily
, which contains
a collection of models with class PLNnetworkfit
See Also
The classes PLNnetworkfamily
and PLNnetworkfit
, and the and the configuration function PLNnetwork_param()
.
Examples
data(trichoptera)
trichoptera <- prepare_data(trichoptera$Abundance, trichoptera$Covariate)
fits <- PLNnetwork(Abundance ~ 1, data = trichoptera)
Control of PLNnetwork fit
Description
Helper to define list of parameters to control the PLN fit. All arguments have defaults.
Usage
PLNnetwork_param(
backend = c("nlopt", "torch"),
inception_cov = c("full", "spherical", "diagonal"),
trace = 1,
n_penalties = 30,
min_ratio = 0.1,
penalize_diagonal = TRUE,
penalty_weights = NULL,
config_post = list(),
config_optim = list(),
inception = NULL
)
Arguments
backend |
optimization back used, either "nlopt" or "torch". Default is "nlopt" |
inception_cov |
Covariance structure used for the inception model used to initialize the PLNfamily. Defaults to "full" and can be constrained to "diagonal" and "spherical". |
trace |
a integer for verbosity. |
n_penalties |
an integer that specifies the number of values for the penalty grid when internally generated. Ignored when penalties is non |
min_ratio |
the penalty grid ranges from the minimal value that produces a sparse to this value multiplied by |
penalize_diagonal |
boolean: should the diagonal terms be penalized in the graphical-Lasso? Default is |
penalty_weights |
either a single or a list of p x p matrix of weights (default: all weights equal to 1) to adapt the amount of shrinkage to each pairs of node. Must be symmetric with positive values. |
config_post |
a list for controlling the post-treatment (optional bootstrap, jackknife, R2, etc). |
config_optim |
a list for controlling the optimizer (either "nlopt" or "torch" backend). See details |
inception |
Set up the parameters initialization: by default, the model is initialized with a multivariate linear model applied on log-transformed data, and with the same formula as the one provided by the user. However, the user can provide a PLNfit (typically obtained from a previous fit), which sometimes speeds up the inference. |
Details
See PLN_param()
for a full description of the generic optimization parameters. PLNnetwork_param() also has two additional parameters controlling the optimization due the inner-outer loop structure of the optimizer:
"ftol_out" outer solver stops when an optimization step changes the objective function by less than ftol multiplied by the absolute value of the parameter. Default is 1e-6
"maxit_out" outer solver stops when the number of iteration exceeds maxit_out. Default is 50
Value
list of parameters configuring the fit.
See Also
An R6 Class to represent a collection of PLNnetworkfit
s
Description
The function PLNnetwork()
produces an instance of this class.
This class comes with a set of methods mostly used to compare
network fits (in terms of goodness of fit) or extract one from
the family (based on penalty parameter and/or goodness of it).
See the documentation for getBestModel()
,
getModel()
and plot() for the user-facing ones.
Super classes
PLNmodels::PLNfamily
-> PLNmodels::Networkfamily
-> PLNnetworkfamily
Methods
Public methods
Inherited methods
PLNmodels::PLNfamily$getModel()
PLNmodels::PLNfamily$postTreatment()
PLNmodels::PLNfamily$print()
PLNmodels::Networkfamily$coefficient_path()
PLNmodels::Networkfamily$getBestModel()
PLNmodels::Networkfamily$optimize()
PLNmodels::Networkfamily$plot()
PLNmodels::Networkfamily$plot_objective()
PLNmodels::Networkfamily$plot_stars()
PLNmodels::Networkfamily$show()
Method new()
Initialize all models in the collection
Usage
PLNnetworkfamily$new(penalties, data, control)
Arguments
penalties
a vector of positive real number controlling the level of sparsity of the underlying network.
data
a named list used internally to carry the data matrices
control
a list for controlling the optimization.
Returns
Update current PLNnetworkfit
with smart starting values
Method stability_selection()
Compute the stability path by stability selection
Usage
PLNnetworkfamily$stability_selection( subsamples = NULL, control = PLNnetwork_param() )
Arguments
subsamples
a list of vectors describing the subsamples. The number of vectors (or list length) determines the number of subsamples used in the stability selection. Automatically set to 20 subsamples with size
10*sqrt(n)
ifn >= 144
and0.8*n
otherwise following Liu et al. (2010) recommendations.control
a list controlling the main optimization process in each call to
PLNnetwork()
. SeePLNnetwork()
andPLN_param()
for details.
Method clone()
The objects of this class are cloneable with this method.
Usage
PLNnetworkfamily$clone(deep = FALSE)
Arguments
deep
Whether to make a deep clone.
See Also
The function PLNnetwork()
, the class PLNnetworkfit
Examples
data(trichoptera)
trichoptera <- prepare_data(trichoptera$Abundance, trichoptera$Covariate)
fits <- PLNnetwork(Abundance ~ 1, data = trichoptera)
class(fits)
An R6 Class to represent a PLNfit in a sparse inverse covariance framework
Description
The function PLNnetwork()
produces a collection of models which are instances of object with class PLNnetworkfit
.
This class comes with a set of methods, some of them being useful for the user:
See the documentation for plot()
and methods inherited from PLNfit
.
Super classes
PLNmodels::PLNfit
-> PLNmodels::PLNfit_fixedcov
-> PLNnetworkfit
Active bindings
vcov_model
character: the model used for the residual covariance
penalty
the global level of sparsity in the current model
penalty_weights
a matrix of weights controlling the amount of penalty element-wise.
n_edges
number of edges if the network (non null coefficient of the sparse precision matrix)
nb_param
number of parameters in the current PLN model
pen_loglik
variational lower bound of the l1-penalized loglikelihood
EBIC
variational lower bound of the EBIC
density
proportion of non-null edges in the network
criteria
a vector with loglik, penalized loglik, BIC, EBIC, ICL, R_squared, number of parameters, number of edges and graph density
Methods
Public methods
Inherited methods
Method new()
Initialize a PLNnetworkfit
object
Usage
PLNnetworkfit$new(data, control)
Arguments
data
a named list used internally to carry the data matrices
control
a list for controlling the optimization.
Method optimize()
Call to the C++ optimizer and update of the relevant fields
Usage
PLNnetworkfit$optimize(data, config)
Arguments
data
a named list used internally to carry the data matrices
config
a list for controlling the optimization
Method latent_network()
Extract interaction network in the latent space
Usage
PLNnetworkfit$latent_network(type = c("partial_cor", "support", "precision"))
Arguments
type
edge value in the network. Can be "support" (binary edges), "precision" (coefficient of the precision matrix) or "partial_cor" (partial correlation between species)
Returns
a square matrix of size PLNnetworkfit$n
Method plot_network()
plot the latent network.
Usage
PLNnetworkfit$plot_network( type = c("partial_cor", "support"), output = c("igraph", "corrplot"), edge.color = c("#F8766D", "#00BFC4"), remove.isolated = FALSE, node.labels = NULL, layout = layout_in_circle, plot = TRUE )
Arguments
type
edge value in the network. Either "precision" (coefficient of the precision matrix) or "partial_cor" (partial correlation between species).
output
Output type. Either
igraph
(for the network) orcorrplot
(for the adjacency matrix)edge.color
Length 2 color vector. Color for positive/negative edges. Default is
c("#F8766D", "#00BFC4")
. Only relevant for igraph output.remove.isolated
if
TRUE
, isolated node are remove before plotting. Only relevant for igraph output.node.labels
vector of character. The labels of the nodes. The default will use the column names ot the response matrix.
layout
an optional igraph layout. Only relevant for igraph output.
plot
logical. Should the final network be displayed or only sent back to the user. Default is
TRUE
.
Method show()
User friendly print method
Usage
PLNnetworkfit$show()
Method clone()
The objects of this class are cloneable with this method.
Usage
PLNnetworkfit$clone(deep = FALSE)
Arguments
deep
Whether to make a deep clone.
See Also
The function PLNnetwork()
, the class PLNnetworkfamily
Examples
## Not run:
data(trichoptera)
trichoptera <- prepare_data(trichoptera$Abundance, trichoptera$Covariate)
nets <- PLNnetwork(Abundance ~ 1, data = trichoptera)
myPLNnet <- getBestModel(nets)
class(myPLNnet)
print(myPLNnet)
## End(Not run)
Zero Inflated Poisson lognormal model
Description
Fit the multivariate Zero Inflated Poisson lognormal model with a variational algorithm. Use the (g)lm syntax for model specification (covariates, offsets, subset).
Usage
ZIPLN(
formula,
data,
subset,
zi = c("single", "row", "col"),
control = ZIPLN_param()
)
Arguments
formula |
an object of class "formula": a symbolic description of the model to be fitted. |
data |
an optional data frame, list or environment (or object coercible by as.data.frame to a data frame) containing the variables in the model. If not found in data, the variables are taken from environment(formula), typically the environment from which PLN is called. |
subset |
an optional vector specifying a subset of observations to be used in the fitting process. |
zi |
a character describing the model used for zero inflation, either of
|
control |
a list-like structure for controlling the optimization, with default generated by |
Details
Covariates for the Zero-Inflation parameter (using a logistic regression model) can be specified in the formula RHS using the pipe
(~ PLN effect | ZI effect
) to separate covariates for the PLN part of the model from those for the Zero-Inflation part.
Note that different covariates can be used for each part.
Value
an R6 object with class ZIPLNfit
See Also
The class ZIPLNfit
Examples
data(trichoptera)
trichoptera <- prepare_data(trichoptera$Abundance, trichoptera$Covariate)
## Use different models for zero-inflation...
myZIPLN_single <- ZIPLN(Abundance ~ 1, data = trichoptera, zi = "single")
## Not run:
myZIPLN_row <- ZIPLN(Abundance ~ 1, data = trichoptera, zi = "row")
myZIPLN_col <- ZIPLN(Abundance ~ 1, data = trichoptera, zi = "col")
## ...including logistic regression on covariates
myZIPLN_covar <- ZIPLN(Abundance ~ 1 | 1 + Wind, data = trichoptera)
## End(Not run)
Control of a ZIPLN fit
Description
Helper to define list of parameters to control the PLN fit. All arguments have defaults.
Usage
ZIPLN_param(
backend = c("nlopt"),
trace = 1,
covariance = c("full", "diagonal", "spherical", "fixed", "sparse"),
Omega = NULL,
penalty = 0,
penalize_diagonal = TRUE,
penalty_weights = NULL,
config_post = list(),
config_optim = list(),
inception = NULL
)
Arguments
backend |
optimization back used, either "nlopt" or "torch". Default is "nlopt" |
trace |
a integer for verbosity. |
covariance |
character setting the model for the covariance matrix. Either "full", "diagonal", "spherical" or "fixed". Default is "full". |
Omega |
precision matrix of the latent variables. Inverse of Sigma. Must be specified if |
penalty |
a user-defined penalty to sparsify the residual covariance. Defaults to 0 (no sparsity). |
penalize_diagonal |
boolean: should the diagonal terms be penalized in the graphical-Lasso? Default is |
penalty_weights |
either a single or a list of p x p matrix of weights (default: all weights equal to 1) to adapt the amount of shrinkage to each pairs of node. Must be symmetric with positive values. |
config_post |
a list for controlling the post-treatments (optional bootstrap, jackknife, R2, etc.). See details |
config_optim |
a list for controlling the optimizer (either "nlopt" or "torch" backend). See details |
inception |
Set up the parameters initialization: by default, the model is initialized with a multivariate linear model applied on log-transformed data, and with the same formula as the one provided by the user. However, the user can provide a PLNfit (typically obtained from a previous fit), which sometimes speeds up the inference. |
Details
See PLN_param()
and PLNnetwork_param()
for a full description of the generic optimization parameters. Like PLNnetwork_param()
, ZIPLN_param() has two parameters controlling the optimization due the inner-outer loop structure of the optimizer:
"ftol_out" outer solver stops when an optimization step changes the objective function by less than
ftol_out
multiplied by the absolute value of the parameter. Default is 1e-6"maxit_out" outer solver stops when the number of iteration exceeds
maxit_out
. Default is 100 and one additional parameter controlling the form of the variational approximation of the zero inflation:"approx_ZI" either uses an exact or approximated conditional distribution for the zero inflation. Default is FALSE
Value
list of parameters used during the fit and post-processing steps
An R6 Class to represent a ZIPLNfit
Description
The function ZIPLN()
fits a model which is an instance of an object with class ZIPLNfit
.
This class comes with a set of R6 methods, some of which are useful for the end-user and exported as S3 methods.
See the documentation for coef()
, sigma()
, predict()
.
Fields are accessed via active binding and cannot be changed by the user.
Details
Covariates for the Zero-Inflation parameter (using a logistic regression model) can be specified in the formula RHS using the pipe
(~ PLN effect | ZI effect
) to separate covariates for the PLN part of the model from those for the Zero-Inflation part.
Note that different covariates can be used for each part.
Active bindings
n
number of samples/sites
q
number of dimensions of the latent space
p
number of variables/species
d
number of covariates in the PLN part
d0
number of covariates in the ZI part
nb_param_zi
number of parameters in the ZI part of the model
nb_param_pln
number of parameters in the PLN part of the model
nb_param
number of parameters in the ZIPLN model
model_par
a list with the matrices of parameters found in the model (B, Sigma, plus some others depending on the variant)
var_par
a list with two matrices, M and S2, which are the estimated parameters in the variational approximation
optim_par
a list with parameters useful for monitoring the optimization
latent
a matrix: values of the latent vector (Z in the model)
latent_pos
a matrix: values of the latent position vector (Z) without covariates effects or offset
fitted
a matrix: fitted values of the observations (A in the model)
vcov_model
character: the model used for the covariance (either "spherical", "diagonal", "full" or "sparse")
zi_model
character: the model used for the zero inflation (either "single", "row", "col" or "covar")
loglik
(weighted) variational lower bound of the loglikelihood
loglik_vec
element-wise variational lower bound of the loglikelihood
BIC
variational lower bound of the BIC
entropy
Entropy of the variational distribution
entropy_ZI
Entropy of the variational distribution
entropy_PLN
Entropy of the Gaussian variational distribution in the PLN component
ICL
variational lower bound of the ICL
criteria
a vector with loglik, BIC, ICL and number of parameters
Methods
Public methods
Method update()
Update a ZIPLNfit
object
Usage
ZIPLNfit$update( B = NA, B0 = NA, Pi = NA, Omega = NA, Sigma = NA, M = NA, S = NA, R = NA, Ji = NA, Z = NA, A = NA, monitoring = NA )
Arguments
B
matrix of regression parameters in the Poisson lognormal component
B0
matrix of regression parameters in the zero inflated component
Pi
Zero inflated probability parameter (either scalar, row-vector, col-vector or matrix)
Omega
precision matrix of the latent variables
Sigma
covariance matrix of the latent variables
M
matrix of mean vectors for the variational approximation
S
matrix of standard deviation parameters for the variational approximation
R
matrix of probabilities for the variational approximation
Ji
vector of variational lower bounds of the log-likelihoods (one value per sample)
Z
matrix of latent vectors (includes covariates and offset effects)
A
matrix of fitted values
monitoring
a list with optimization monitoring quantities
Returns
Update the current ZIPLNfit
object
Method new()
Initialize a ZIPLNfit
model
Usage
ZIPLNfit$new(data, control)
Arguments
data
a named list used internally to carry the data matrices
control
a list for controlling the optimization. See details.
Method optimize()
Call to the Cpp optimizer and update of the relevant fields
Usage
ZIPLNfit$optimize(data, control)
Arguments
data
a named list used internally to carry the data matrices
control
a list for controlling the optimization. See details.
Method optimize_vestep()
Result of one call to the VE step of the optimization procedure: optimal variational parameters (M, S, R) and corresponding log likelihood values for fixed model parameters (Sigma, B, B0). Intended to position new data in the latent space.
Usage
ZIPLNfit$optimize_vestep( data, B = self$model_par$B, B0 = self$model_par$B0, Omega = self$model_par$Omega, control = ZIPLN_param(backend = "nlopt")$config_optim )
Arguments
data
a named list used internally to carry the data matrices
B
Optional fixed value of the regression parameters in the PLN component
B0
Optional fixed value of the regression parameters in the ZI component
Omega
inverse variance-covariance matrix of the latent variables
control
a list for controlling the optimization. See details.
Returns
A list with three components:
the matrix
M
of variational means,the matrix
S
of variational standard deviationsthe matrix
R
of variational ZI probabilitiesthe vector
Ji
of (variational) log-likelihood of each new observationa list
monitoring
with information about convergence status
Method predict()
Predict position, scores or observations of new data. See predict.ZIPLNfit()
for the S3 method and additional details
Usage
ZIPLNfit$predict( newdata, responses = NULL, type = c("link", "response", "deflated"), level = 1, envir = parent.frame() )
Arguments
newdata
A data frame in which to look for variables with which to predict. If omitted, the fitted values are used.
responses
Optional data frame containing the count of the observed variables (matching the names of the provided as data in the PLN function), assuming the interest in in testing the model.
type
Scale used for the prediction. Either
"link"
(default, predicted positions in the latent space),"response"
(predicted average counts, accounting for zero-inflation) or"deflated"
(predicted average counts, not accounting for zero-inflation and using only the PLN part of the model).level
Optional integer value the level to be used in obtaining the predictions. Level zero corresponds to the population predictions (default if
responses
is not provided) while level one (default) corresponds to predictions after evaluating the variational parameters for the new data.envir
Environment in which the prediction is evaluated
Returns
A matrix with predictions scores or counts.
Method show()
User friendly print method
Usage
ZIPLNfit$show( model = paste("A multivariate Zero Inflated Poisson Lognormal fit with", self$vcov_model, "covariance model.\n") )
Arguments
model
First line of the print output
Method print()
User friendly print method
Usage
ZIPLNfit$print()
Method clone()
The objects of this class are cloneable with this method.
Usage
ZIPLNfit$clone(deep = FALSE)
Arguments
deep
Whether to make a deep clone.
Examples
## Not run:
# See other examples in function ZIPLN
data(trichoptera)
trichoptera <- prepare_data(trichoptera$Abundance, trichoptera$Covariate)
myPLN <- ZIPLN(Abundance ~ 1, data = trichoptera)
class(myPLN)
print(myPLN)
## End(Not run)
An R6 Class to represent a ZIPLNfit in a standard, general framework, with diagonal residual covariance
Description
An R6 Class to represent a ZIPLNfit in a standard, general framework, with diagonal residual covariance
An R6 Class to represent a ZIPLNfit in a standard, general framework, with diagonal residual covariance
Super class
PLNmodels::ZIPLNfit
-> ZIPLNfit_diagonal
Active bindings
nb_param_pln
number of parameters in the PLN part of the current model
vcov_model
character: the model used for the residual covariance
Methods
Public methods
Inherited methods
Method new()
Initialize a ZIPLNfit_diagonal
model
Usage
ZIPLNfit_diagonal$new(data, control)
Arguments
data
a named list used internally to carry the data matrices
control
a list for controlling the optimization. See details.
Method clone()
The objects of this class are cloneable with this method.
Usage
ZIPLNfit_diagonal$clone(deep = FALSE)
Arguments
deep
Whether to make a deep clone.
Examples
## Not run:
# See other examples in function ZIPLN
data(trichoptera)
trichoptera <- prepare_data(trichoptera$Abundance, trichoptera$Covariate)
myPLN <- ZIPLN(Abundance ~ 1, data = trichoptera, control = ZIPLN_param(covariance = "diagonal"))
class(myPLN)
print(myPLN)
## End(Not run)
An R6 Class to represent a ZIPLNfit in a standard, general framework, with fixed (inverse) residual covariance
Description
An R6 Class to represent a ZIPLNfit in a standard, general framework, with fixed (inverse) residual covariance
An R6 Class to represent a ZIPLNfit in a standard, general framework, with fixed (inverse) residual covariance
Super class
PLNmodels::ZIPLNfit
-> ZIPLNfit_fixed
Active bindings
nb_param_pln
number of parameters in the PLN part of the current model
vcov_model
character: the model used for the residual covariance
Methods
Public methods
Inherited methods
Method new()
Initialize a ZIPLNfit_fixed
model
Usage
ZIPLNfit_fixed$new(data, control)
Arguments
data
a named list used internally to carry the data matrices
control
a list for controlling the optimization. See details.
Method clone()
The objects of this class are cloneable with this method.
Usage
ZIPLNfit_fixed$clone(deep = FALSE)
Arguments
deep
Whether to make a deep clone.
Examples
## Not run:
# See other examples in function ZIPLN
data(trichoptera)
trichoptera <- prepare_data(trichoptera$Abundance, trichoptera$Covariate)
myPLN <- ZIPLN(Abundance ~ 1, data = trichoptera,
control = ZIPLN_param(Omega = diag(ncol(trichoptera$Abundance))))
class(myPLN)
print(myPLN)
## End(Not run)
An R6 Class to represent a ZIPLNfit in a standard, general framework, with sparse inverse residual covariance
Description
An R6 Class to represent a ZIPLNfit in a standard, general framework, with sparse inverse residual covariance
An R6 Class to represent a ZIPLNfit in a standard, general framework, with sparse inverse residual covariance
Super class
PLNmodels::ZIPLNfit
-> ZIPLNfit_sparse
Active bindings
penalty
the global level of sparsity in the current model
penalty_weights
a matrix of weights controlling the amount of penalty element-wise.
n_edges
number of edges if the network (non null coefficient of the sparse precision matrix)
nb_param_pln
number of parameters in the PLN part of the current model
vcov_model
character: the model used for the residual covariance
pen_loglik
variational lower bound of the l1-penalized loglikelihood
EBIC
variational lower bound of the EBIC
density
proportion of non-null edges in the network
criteria
a vector with loglik, penalized loglik, BIC, EBIC, ICL, R_squared, number of parameters, number of edges and graph density
Methods
Public methods
Inherited methods
Method new()
Initialize a ZIPLNfit_fixed
model
Usage
ZIPLNfit_sparse$new(data, control)
Arguments
data
a named list used internally to carry the data matrices
control
a list for controlling the optimization. See details.
Method latent_network()
Extract interaction network in the latent space
Usage
ZIPLNfit_sparse$latent_network(type = c("partial_cor", "support", "precision"))
Arguments
type
edge value in the network. Can be "support" (binary edges), "precision" (coefficient of the precision matrix) or "partial_cor" (partial correlation between species)
Returns
a square matrix of size ZIPLNfit_sparse$n
Method plot_network()
plot the latent network.
Usage
ZIPLNfit_sparse$plot_network( type = c("partial_cor", "support"), output = c("igraph", "corrplot"), edge.color = c("#F8766D", "#00BFC4"), remove.isolated = FALSE, node.labels = NULL, layout = layout_in_circle, plot = TRUE )
Arguments
type
edge value in the network. Either "precision" (coefficient of the precision matrix) or "partial_cor" (partial correlation between species).
output
Output type. Either
igraph
(for the network) orcorrplot
(for the adjacency matrix)edge.color
Length 2 color vector. Color for positive/negative edges. Default is
c("#F8766D", "#00BFC4")
. Only relevant for igraph output.remove.isolated
if
TRUE
, isolated node are remove before plotting. Only relevant for igraph output.node.labels
vector of character. The labels of the nodes. The default will use the column names ot the response matrix.
layout
an optional igraph layout. Only relevant for igraph output.
plot
logical. Should the final network be displayed or only sent back to the user. Default is
TRUE
.
Method clone()
The objects of this class are cloneable with this method.
Usage
ZIPLNfit_sparse$clone(deep = FALSE)
Arguments
deep
Whether to make a deep clone.
Examples
## Not run:
# See other examples in function ZIPLN
data(trichoptera)
trichoptera <- prepare_data(trichoptera$Abundance, trichoptera$Covariate)
myPLN <- ZIPLN(Abundance ~ 1, data = trichoptera, control= ZIPLN_param(penalty = 1))
class(myPLN)
print(myPLN)
plot(myPLN)
## End(Not run)
An R6 Class to represent a ZIPLNfit in a standard, general framework, with spherical residual covariance
Description
An R6 Class to represent a ZIPLNfit in a standard, general framework, with spherical residual covariance
An R6 Class to represent a ZIPLNfit in a standard, general framework, with spherical residual covariance
Super class
PLNmodels::ZIPLNfit
-> ZIPLNfit_spherical
Active bindings
nb_param_pln
number of parameters in the PLN part of the current model
vcov_model
character: the model used for the residual covariance
Methods
Public methods
Inherited methods
Method new()
Initialize a ZIPLNfit_spherical
model
Usage
ZIPLNfit_spherical$new(data, control)
Arguments
data
a named list used internally to carry the data matrices
control
a list for controlling the optimization. See details.
Method clone()
The objects of this class are cloneable with this method.
Usage
ZIPLNfit_spherical$clone(deep = FALSE)
Arguments
deep
Whether to make a deep clone.
Examples
## Not run:
# See other examples in function ZIPLN
data(trichoptera)
trichoptera <- prepare_data(trichoptera$Abundance, trichoptera$Covariate)
myPLN <- ZIPLN(Abundance ~ 1, data = trichoptera, control = ZIPLN_param(covariance = "spherical"))
class(myPLN)
print(myPLN)
## End(Not run)
Zero Inflated Sparse Poisson lognormal model for network inference
Description
Perform sparse inverse covariance estimation for the Zero Inflated Poisson lognormal model using a variational algorithm. Iterate over a range of logarithmically spaced sparsity parameter values. Use the (g)lm syntax to specify the model (including covariates and offsets).
Usage
ZIPLNnetwork(
formula,
data,
subset,
weights,
zi = c("single", "row", "col"),
penalties = NULL,
control = ZIPLNnetwork_param()
)
Arguments
formula |
an object of class "formula": a symbolic description of the model to be fitted. |
data |
an optional data frame, list or environment (or object coercible by as.data.frame to a data frame) containing the variables in the model. If not found in data, the variables are taken from environment(formula), typically the environment from which lm is called. |
subset |
an optional vector specifying a subset of observations to be used in the fitting process. |
weights |
an optional vector of observation weights to be used in the fitting process. |
zi |
a character describing the model used for zero inflation, either of
|
penalties |
an optional vector of positive real number controlling the level of sparsity of the underlying network. if NULL (the default), will be set internally. See |
control |
a list-like structure for controlling the optimization, with default generated by |
Details
Covariates for the Zero-Inflation parameter (using a logistic regression model) can be specified in the formula RHS using the pipe
(~ PLN effect | ZI effect
) to separate covariates for the PLN part of the model from those for the Zero-Inflation part.
Note that different covariates can be used for each part.
Value
an R6 object with class ZIPLNnetworkfamily
See Also
The classes ZIPLNfit
and ZIPLNnetworkfamily
Examples
data(trichoptera)
trichoptera <- prepare_data(trichoptera$Abundance, trichoptera$Covariate)
myZIPLNs <- ZIPLNnetwork(Abundance ~ 1, data = trichoptera, zi = "single")
Control of ZIPLNnetwork fit
Description
Helper to define list of parameters to control the ZIPLNnetwork fit. All arguments have defaults.
Usage
ZIPLNnetwork_param(
backend = c("nlopt"),
inception_cov = c("full", "spherical", "diagonal"),
trace = 1,
n_penalties = 30,
min_ratio = 0.1,
penalize_diagonal = TRUE,
penalty_weights = NULL,
config_post = list(),
config_optim = list(),
inception = NULL
)
Arguments
backend |
optimization back used, either "nlopt" or "torch". Default is "nlopt" |
inception_cov |
Covariance structure used for the inception model used to initialize the PLNfamily. Defaults to "full" and can be constrained to "diagonal" and "spherical". |
trace |
a integer for verbosity. |
n_penalties |
an integer that specifies the number of values for the penalty grid when internally generated. Ignored when penalties is non |
min_ratio |
the penalty grid ranges from the minimal value that produces a sparse to this value multiplied by |
penalize_diagonal |
boolean: should the diagonal terms be penalized in the graphical-Lasso? Default is |
penalty_weights |
either a single or a list of p x p matrix of weights (default: all weights equal to 1) to adapt the amount of shrinkage to each pairs of node. Must be symmetric with positive values. |
config_post |
a list for controlling the post-treatment (optional bootstrap, jackknife, R2, etc). |
config_optim |
a list for controlling the optimizer (either "nlopt" or "torch" backend). See details |
inception |
Set up the parameters initialization: by default, the model is initialized with a multivariate linear model applied on log-transformed data, and with the same formula as the one provided by the user. However, the user can provide a PLNfit (typically obtained from a previous fit), which sometimes speeds up the inference. |
Details
See PLNnetwork_param()
for a full description of the optimization parameters. Note that some defaults values are different than those used in PLNnetwork_param()
:
"ftol_out" (outer loop convergence tolerance the objective function) is set by default to 1e-6
"maxit_out" (max number of iterations for the outer loop) is set by default to 100
Value
list of parameters configuring the fit.
See Also
PLNnetwork_param()
and PLN_param()
An R6 Class to represent a collection of ZIPLNnetwork
Description
The function ZIPLNnetwork()
produces an instance of this class.
This class comes with a set of methods, some of them being useful for the user:
See the documentation for getBestModel()
,
getModel()
and plot()
Super classes
PLNmodels::PLNfamily
-> PLNmodels::Networkfamily
-> ZIPLNnetworkfamily
Public fields
covariates0
the matrix of covariates included in the ZI component
Methods
Public methods
Inherited methods
PLNmodels::PLNfamily$getModel()
PLNmodels::PLNfamily$postTreatment()
PLNmodels::PLNfamily$print()
PLNmodels::Networkfamily$coefficient_path()
PLNmodels::Networkfamily$getBestModel()
PLNmodels::Networkfamily$optimize()
PLNmodels::Networkfamily$plot()
PLNmodels::Networkfamily$plot_objective()
PLNmodels::Networkfamily$plot_stars()
PLNmodels::Networkfamily$show()
Method new()
Initialize all models in the collection
Usage
ZIPLNnetworkfamily$new(penalties, data, control)
Arguments
penalties
a vector of positive real number controlling the level of sparsity of the underlying network.
data
a named list used internally to carry the data matrices
control
a list for controlling the optimization.
Returns
Update current PLNnetworkfit
with smart starting values
Method stability_selection()
Compute the stability path by stability selection
Usage
ZIPLNnetworkfamily$stability_selection( subsamples = NULL, control = ZIPLNnetwork_param() )
Arguments
subsamples
a list of vectors describing the subsamples. The number of vectors (or list length) determines the number of subsamples used in the stability selection. Automatically set to 20 subsamples with size
10*sqrt(n)
ifn >= 144
and0.8*n
otherwise following Liu et al. (2010) recommendations.control
a list controlling the main optimization process in each call to
PLNnetwork()
. SeeZIPLNnetwork()
andZIPLN_param()
for details.
Method clone()
The objects of this class are cloneable with this method.
Usage
ZIPLNnetworkfamily$clone(deep = FALSE)
Arguments
deep
Whether to make a deep clone.
See Also
The function ZIPLNnetwork()
, the class ZIPLNfit_sparse
Examples
data(trichoptera)
trichoptera <- prepare_data(trichoptera$Abundance, trichoptera$Covariate)
fits <- PLNnetwork(Abundance ~ 1, data = trichoptera)
class(fits)
Barents fish data set
Description
This data set gives the abundance of 30 fish species observed in 89 sites in the Barents sea. For each site, 4 additional covariates are known. Subsample of the original datasets studied by Fossheim et al, 2006.
Usage
barents
Format
A data frame with 6 variables:
Abundance: A 30 fish species by 89 sites count matrix
Offset: A 30 fish species by 89 samples offset matrix, measuring the sampling effort in each site
4 covariates for latitude, longitude, depth (in meters), temperature (in Celsius degrees).
Source
Data from M. Fossheim and coauthors.
References
Fossheim, Maria, Einar M. Nilssen, and Michaela Aschan. "Fish assemblages in the Barents Sea." Marine Biology Research 2.4 (2006). doi:10.1080/17451000600815698
Examples
data(barents)
Extracts model coefficients from objects returned by PLNLDA()
Description
The method for objects returned by PLNLDA()
only returns
coefficients associated to the
\Theta
part of the model (see the PLNLDA vignette for mathematical details).
Usage
## S3 method for class 'PLNLDAfit'
coef(object, ...)
Arguments
object |
an R6 object with class PLNLDAfit |
... |
additional parameters for S3 compatibility. Not used |
Value
Either NULL or a matrix of coefficients extracted from the PLNLDAfit model.
Examples
data(trichoptera)
trichoptera <- prepare_data(trichoptera$Abundance, trichoptera$Covariate)
myPLNLDA <- PLNLDA(Abundance ~ Wind, grouping = Group, data = trichoptera)
coef(myPLNLDA)
Extract model coefficients
Description
Extracts model coefficients from objects returned by PLN()
and its variants
Usage
## S3 method for class 'PLNfit'
coef(object, type = c("main", "covariance"), ...)
Arguments
object |
an R6 object with class |
type |
type of parameter that should be extracted. Either "main" (default) for
or "covariance" for
|
... |
additional parameters for S3 compatibility. Not used |
Value
A matrix of coefficients extracted from the PLNfit model.
See Also
sigma.PLNfit()
, vcov.PLNfit()
, standard_error.PLNfit()
Examples
data(trichoptera)
trichoptera <- prepare_data(trichoptera$Abundance, trichoptera$Covariate)
myPLN <- PLN(Abundance ~ 1 + offset(log(Offset)), data = trichoptera)
coef(myPLN) ## B
coef(myPLN, type = "covariance") ## Sigma
Extract model coefficients
Description
Extracts model coefficients from objects returned by PLN()
and its variants
Usage
## S3 method for class 'PLNmixturefit'
coef(object, type = c("main", "means", "covariance", "mixture"), ...)
Arguments
object |
an R6 object with class |
type |
type of parameter that should be extracted. Either "main" (default) for
, "means" for
, "mixture" for
or "covariance" for
|
... |
additional parameters for S3 compatibility. Not used |
Value
A matrix of coefficients extracted from the PLNfit model.
See Also
Examples
data(trichoptera)
trichoptera <- prepare_data(trichoptera$Abundance, trichoptera$Covariate)
myPLN <- PLNmixture(Abundance ~ 1 + offset(log(Offset)),
data = trichoptera, control = PLNmixture_param(smoothing = "none")) %>% getBestModel()
coef(myPLN) ## Theta - empty here
coef(myPLN, type = "mixture") ## pi
coef(myPLN, type = "means") ## mu
coef(myPLN, type = "covariance") ## Sigma
Extract model coefficients
Description
Extracts model coefficients from objects returned by ZIPLN()
and its variants
Usage
## S3 method for class 'ZIPLNfit'
coef(object, type = c("count", "zero", "precision", "covariance"), ...)
Arguments
object |
an R6 object with class |
type |
type of parameter that should be extracted. Either "count" (default) for |
... |
additional parameters for S3 compatibility. Not used |
Value
A matrix of coefficients extracted from the ZIPLNfit model.
See Also
Examples
data(scRNA)
# data subsample: only 100 random cell and the 50 most varying transcript
subset <- sample.int(nrow(scRNA), 100)
myPLN <- ZIPLN(counts[, 1:50] ~ 1 + offset(log(total_counts)), subset = subset, data = scRNA)
Extract the regularization path of a PLNnetwork fit
Description
Extract the regularization path of a PLNnetwork fit
Usage
coefficient_path(Robject, precision = TRUE, corr = TRUE)
Arguments
Robject |
an object with class |
precision |
a logical, should the coefficients of the precision matrix Omega or the covariance matrix Sigma be sent back. Default is |
corr |
a logical, should the correlation (partial in case |
Value
Sends back a tibble/data.frame.
Examples
data(trichoptera)
trichoptera <- prepare_data(trichoptera$Abundance, trichoptera$Covariate)
fits <- PLNnetwork(Abundance ~ 1, data = trichoptera)
head(coefficient_path(fits))
Helper function for PLN initialization.
Description
Barebone function to compute starting points for B, M and S when fitting a PLN. Mostly intended for internal use.
Usage
compute_PLN_starting_point(Y, X, O, w, s = 0.1)
Arguments
Y |
Response count matrix |
X |
Covariate matrix |
O |
Offset matrix (in log-scale) |
w |
Weight vector (defaults to 1) |
s |
Scale parameter for S (defaults to 0.1) |
Details
The default strategy to estimate B and M is to fit a linear model with covariates X
to the response count matrix (after adding a pseudocount of 1, scaling by the offset and taking the log). The regression matrix is used to initialize B
and the residuals to initialize M
. S
is initialized as a constant conformable matrix with value s
.
Value
a named list of starting values for model parameter B and variational parameters M and S used in the iterative optimization algorithm of PLN()
Examples
## Not run:
data(barents)
Y <- barents$Abundance
X <- model.matrix(Abundance ~ Latitude + Longitude + Depth + Temperature, data = barents)
O <- log(barents$Offset)
w <-- rep(1, nrow(Y))
compute_PLN_starting_point(Y, X, O, w)
## End(Not run)
Compute offsets from a count data using one of several normalization schemes
Description
Computes offsets from the count table using one of several normalization schemes (TSS, CSS, RLE, GMPR, Wrench, TMM, etc) described in the literature.
Usage
compute_offset(
counts,
offset = c("TSS", "GMPR", "RLE", "CSS", "Wrench", "TMM", "none"),
scale = c("none", "count"),
...
)
Arguments
counts |
Required. An abundance count table, preferably with dimensions names and species as columns. |
offset |
Optional. Normalization scheme used to compute scaling factors used as offset during PLN inference. Available schemes are "TSS" (Total Sum Scaling, default), "CSS" (Cumulative Sum Scaling, used in metagenomeSeq), "RLE" (Relative Log Expression, used in DESeq2), "GMPR" (Geometric Mean of Pairwise Ratio, introduced in Chen et al., 2018), Wrench (introduced in Kumar et al., 2018) or "none". Alternatively the user can supply its own vector or matrix of offsets (see note for specification of the user-supplied offsets). |
scale |
Either |
... |
Additional parameters passed on to specific methods (for now CSS and RLE) |
Details
RLE has additional pseudocounts
and type
arguments to add pseudocounts to the observed counts (defaults to 0L) and to compute offsets using only positive counts (if type == "poscounts"
). This mimics the behavior of DESeq2::DESeq()
when using sfType == "poscounts"
. CSS has an additional reference
argument to choose the location function used to compute the reference quantiles (defaults to median
as in the Nature publication but can be set to mean
to reproduce behavior of functions cumNormStat* from metagenomeSeq). Wrench has two additional parameters: groups
to specify sample groups and type
to either reproduce exactly the default Wrench::wrench()
behavior (type = "wrench"
, default) or to use simpler heuristics (type = "simple"
). Note that (i) CSS normalization fails when the median absolute deviation around quantiles does not become instable for high quantiles (limited count variations both within and across samples) and/or one sample has less than two positive counts, (ii) RLE fails when there are no common species across all samples (unless type == "poscounts"
has been specified) and (iii) GMPR fails if a sample does not share any species with all other samples.
TMM code between two libraries is simplified and adapted from M. Robinson (edgeR:::.calcFactorTMM).
The final output is however different from the one produced by edgeR:::.calcFactorTMM as they are intended
to be used as such in the model (whereas they need to be multiplied by sequencing depths in edgeR)
Value
If offset = "none"
, NULL
else a vector of length nrow(counts)
with one offset per sample.
References
Chen, L., Reeve, J., Zhang, L., Huang, S., Wang, X. and Chen, J. (2018) GMPR: A robust normalization method for zero-inflated count data with application to microbiome sequencing data. PeerJ, 6, e4600 doi:10.7717/peerj.4600
Paulson, J. N., Colin Stine, O., Bravo, H. C. and Pop, M. (2013) Differential abundance analysis for microbial marker-gene surveys. Nature Methods, 10, 1200-1202 doi:10.1038/nmeth.2658
Anders, S. and Huber, W. (2010) Differential expression analysis for sequence count data. Genome Biology, 11, R106 doi:10.1186/gb-2010-11-10-r106
Kumar, M., Slud, E., Okrah, K. et al. (2018) Analysis and correction of compositional bias in sparse sequencing count data. BMC Genomics 19, 799 doi:10.1186/s12864-018-5160-5
Robinson, M.D., Oshlack, A. (2010) A scaling normalization method for differential expression analysis of RNA-seq data. Genome Biol 11, R25 doi:10.1186/gb-2010-11-3-r25
Examples
data(trichoptera)
counts <- trichoptera$Abundance
compute_offset(counts)
## Other normalization schemes
compute_offset(counts, offset = "RLE", pseudocounts = 1)
compute_offset(counts, offset = "Wrench", groups = trichoptera$Covariate$Group)
compute_offset(counts, offset = "GMPR")
compute_offset(counts, offset = "TMM")
## User supplied offsets
my_offset <- setNames(rep(1, nrow(counts)), rownames(counts))
compute_offset(counts, offset = my_offset)
Extract edge selection frequency in bootstrap subsamples
Description
Extracts edge selection frequency in networks reconstructed from bootstrap subsamples during the stars stability selection procedure, as either a matrix or a named vector. In the latter case, edge names follow igraph naming convention.
Usage
extract_probs(
Robject,
penalty = NULL,
index = NULL,
crit = c("StARS", "BIC", "EBIC"),
format = c("matrix", "vector"),
tol = 1e-05
)
Arguments
Robject |
an object with class |
penalty |
penalty used for the bootstrap subsamples |
index |
Integer index of the model to be returned. Only the first value is taken into account. |
crit |
a character for the criterion used to performed the selection. Either
"BIC", "ICL", "EBIC", "StARS", "R_squared". Default is |
format |
output format. Either a matrix (default) or a named vector. |
tol |
tolerance for rounding error when comparing penalties. |
Value
Either a matrix or named vector of edge-wise probabilities. In the latter case, edge names follow igraph convention.
Examples
data(trichoptera)
trichoptera <- prepare_data(trichoptera$Abundance, trichoptera$Covariate)
nets <- PLNnetwork(Abundance ~ 1 + offset(log(Offset)), data = trichoptera)
## Not run:
stability_selection(nets)
probs <- extract_probs(nets, crit = "StARS", format = "vector")
probs
## End(Not run)
## Not run:
## Add edge attributes to graph using igraph
net_stars <- getBestModel(nets, "StARS")
g <- plot(net_stars, type = "partial_cor", plot=F)
library(igraph)
E(g)$prob <- probs[as_ids(E(g))]
g
## End(Not run)
Extracts model fitted values from objects returned by PLN()
and its variants
Description
Extracts model fitted values from objects returned by PLN()
and its variants
Usage
## S3 method for class 'PLNfit'
fitted(object, ...)
Arguments
object |
an R6 object with class |
... |
additional parameters for S3 compatibility. Not used |
Value
A matrix of Fitted values extracted from the object object.
Extracts model fitted values from objects returned by PLNmixture()
and its variants
Description
Extracts model fitted values from objects returned by PLNmixture()
and its variants
Usage
## S3 method for class 'PLNmixturefit'
fitted(object, ...)
Arguments
object |
an R6 object with class |
... |
additional parameters for S3 compatibility. Not used |
Value
A matrix of Fitted values extracted from the object object.
Extracts model fitted values from objects returned by ZIPLN()
and its variants
Description
Extracts model fitted values from objects returned by ZIPLN()
and its variants
Usage
## S3 method for class 'ZIPLNfit'
fitted(object, ...)
Arguments
object |
an R6 object with class |
... |
additional parameters for S3 compatibility. Not used |
Value
A matrix of Fitted values extracted from the object object.
Best model extraction from a collection of models
Description
Best model extraction from a collection of models
Usage
## S3 method for class 'PLNPCAfamily'
getBestModel(Robject, crit = c("ICL", "BIC"), ...)
getBestModel(Robject, crit, ...)
## S3 method for class 'PLNmixturefamily'
getBestModel(Robject, crit = c("ICL", "BIC"), ...)
## S3 method for class 'Networkfamily'
getBestModel(Robject, crit = c("BIC", "EBIC", "StARS"), ...)
## S3 method for class 'PLNnetworkfamily'
getBestModel(Robject, crit = c("BIC", "EBIC", "StARS"), ...)
## S3 method for class 'ZIPLNnetworkfamily'
getBestModel(Robject, crit = c("BIC", "EBIC", "StARS"), ...)
Arguments
Robject |
an object with class PLNPCAfamilly ot PLNnetworkfamily |
crit |
a character for the criterion used to performed the selection. Either
"BIC", "ICL", "EBIC", "StARS", "R_squared". Default is |
... |
additional parameters for StARS criterion (only for |
Value
Send back an object with class PLNPCAfit
or PLNnetworkfit
Methods (by class)
-
getBestModel(PLNPCAfamily)
: Model extraction forPLNPCAfamily
-
getBestModel(PLNmixturefamily)
: Model extraction forPLNmixturefamily
-
getBestModel(Networkfamily)
: Model extraction forPLNnetworkfamily
orZIPLNnetworkfamily
-
getBestModel(PLNnetworkfamily)
: Model extraction forPLNnetworkfamily
-
getBestModel(ZIPLNnetworkfamily)
: Model extraction forZIPLNnetworkfamily
Examples
## Not run:
data(trichoptera)
trichoptera <- prepare_data(trichoptera$Abundance, trichoptera$Covariate)
myPCA <- PLNPCA(Abundance ~ 1 + offset(log(Offset)), data = trichoptera, ranks = 1:4)
myModel <- getBestModel(myPCA)
## End(Not run)
Model extraction from a collection of models
Description
Model extraction from a collection of models
Usage
## S3 method for class 'PLNPCAfamily'
getModel(Robject, var, index = NULL)
getModel(Robject, var, index)
## S3 method for class 'PLNmixturefamily'
getModel(Robject, var, index = NULL)
## S3 method for class 'Networkfamily'
getModel(Robject, var, index = NULL)
## S3 method for class 'PLNnetworkfamily'
getModel(Robject, var, index = NULL)
## S3 method for class 'ZIPLNnetworkfamily'
getModel(Robject, var, index = NULL)
Arguments
Robject |
an R6 object with class |
var |
value of the parameter ( |
index |
Integer index of the model to be returned. Only the first value is taken into account. |
Value
Sends back an object with class PLNPCAfit
or PLNnetworkfit
.
Methods (by class)
-
getModel(PLNPCAfamily)
: Model extraction forPLNPCAfamily
-
getModel(PLNmixturefamily)
: Model extraction forPLNmixturefamily
-
getModel(Networkfamily)
: Model extraction forPLNnetworkfamily
orZIPLNnetworkfamily
-
getModel(PLNnetworkfamily)
: Model extraction forPLNnetworkfamily
-
getModel(ZIPLNnetworkfamily)
: Model extraction forZIPLNnetworkfamily
Examples
## Not run:
data(trichoptera)
trichoptera <- prepare_data(trichoptera$Abundance, trichoptera$Covariate)
myPCA <- PLNPCA(Abundance ~ 1 + offset(log(Offset)), data = trichoptera, ranks = 1:5)
myModel <- getModel(myPCA, 2)
## End(Not run)
Mollusk data set
Description
This data set gives the abundance of 32 mollusk species in 163 samples. For each sample, 4 additional covariates are known.
Usage
mollusk
Format
A list with 2 two data frames:
- Abundance
a 163 x 32 data frame of abundancies/counts (163 samples and 32 mollusk species)
- Covariate
a 163 x 4 data frame of covariates:
- site
a factor with 8 levels indicating the sampling site
- season
a factor with 4 levels indicating the season
- method
a factor with 2 levels for the method of sampling - wood or string
- duration
a numeric with 3 levels for the time of exposure in week
In order to prepare the data for using formula in multivariate analysis (multiple outputs and inputs), use prepare_data()
.
Original data set has been extracted from ade4.
Source
Data from Richardot-Coulet, Chessel and Bournaud.
References
Richardot-Coulet, M., Chessel D. and Bournaud M. (1986) Typological value of the benthos of old beds of a large river. Methodological approach. Archiv fùr Hydrobiologie, 107, 363–383.
See Also
Examples
data(mollusk)
mollusc <- prepare_data(mollusk$Abundance, mollusk$Covariate)
Oaks amplicon data set
Description
This data set gives the abundance of 114 taxa (66 bacterial OTU, 48 fungal OTUs) in 116 samples. For each sample, 11 additional covariates are known.
Usage
oaks
Format
A data frame with 13 variables:
Abundance: A 114 taxa by 116 samples count matrix
Offset: A 114 taxa by 116 samples offset matrix
Sample: Unique sample id
tree: Tree status with respect to the pathogen (susceptible, intermediate or resistant)
branch: Unique branch id in each tree (4 branches were sampled in each tree, with 10 leaves per branch)
leafNO: Unique leaf id in each tree (40 leaves were sampled in each tree)
distTObase: Distance of the sampled leaf to the base of the branch
distTOtrunk: Distance of the sampled leaf to the base of the tree trunk
distTOground: Distance of the sampled leaf to the base of the ground
pmInfection: Powdery mildew infection, proportion of the upper leaf area displaying mildew symptoms
orientation: Orientation of the branch (South-West SW or North-East NE)
readsTOTfun: Total number of ITS1 reads for that leaf
readsTOTbac: Total number of 16S reads for that leaf
Source
Data from B. Jakuschkin and coauthors.
References
Jakuschkin, B., Fievet, V., Schwaller, L. et al. Deciphering the Pathobiome: Intra- and Interkingdom Interactions Involving the Pathogen Erysiphe alphitoides . Microb Ecol 72, 870–880 (2016). doi:10.1007/s00248-016-0777-x
See Also
Examples
data(oaks)
## Not run:
oaks_networks <- PLNnetwork(formula = Abundance ~ 1 + offset(log(Offset)), data = oaks)
## End(Not run)
Display various outputs (goodness-of-fit criteria, robustness, diagnostic) associated with a collection of network fits (either PLNnetworkfamily
or ZIPLNnetworkfamily
)
Description
Display various outputs (goodness-of-fit criteria, robustness, diagnostic) associated with a collection of network fits (either PLNnetworkfamily
or ZIPLNnetworkfamily
)
Usage
## S3 method for class 'Networkfamily'
plot(
x,
type = c("criteria", "stability", "diagnostic"),
criteria = c("loglik", "pen_loglik", "BIC", "EBIC"),
reverse = FALSE,
log.x = TRUE,
stability = 0.9,
...
)
## S3 method for class 'PLNnetworkfamily'
plot(
x,
type = c("criteria", "stability", "diagnostic"),
criteria = c("loglik", "pen_loglik", "BIC", "EBIC"),
reverse = FALSE,
log.x = TRUE,
stability = 0.9,
...
)
## S3 method for class 'ZIPLNnetworkfamily'
plot(
x,
type = c("criteria", "stability", "diagnostic"),
criteria = c("loglik", "pen_loglik", "BIC", "EBIC"),
reverse = FALSE,
log.x = TRUE,
stability = 0.9,
...
)
Arguments
x |
an R6 object with class |
type |
a character, either "criteria", "stability" or "diagnostic" for the type of plot. |
criteria |
Vector of criteria to plot, to be selected among "loglik" (log-likelihood),
"BIC", "ICL", "R_squared", "EBIC" and "pen_loglik" (penalized log-likelihood).
Default is c("loglik", "pen_loglik", "BIC", "EBIC"). Only used when |
reverse |
A logical indicating whether to plot the value of the criteria in the "natural" direction (loglik - 0.5 penalty) or in the "reverse" direction (-2 loglik + penalty). Default to FALSE, i.e use the natural direction, on the same scale as the log-likelihood. |
log.x |
logical: should the x-axis be represented in log-scale? Default is |
stability |
scalar: the targeted level of stability in stability plot. Default is .9. |
... |
additional parameters for S3 compatibility. Not used |
Details
The BIC and ICL criteria have the form 'loglik - 1/2 * penalty'
so that they are on the same scale as the model log-likelihood. You can change this direction and use the alternate form '-2*loglik + penalty', as some authors do, by setting reverse = TRUE
.
Value
Produces either a diagnostic plot (with type = 'diagnostic'
), a stability plot
(with type = 'stability'
) or the evolution of the criteria of the different models considered
(with type = 'criteria'
, the default).
Functions
-
plot(PLNnetworkfamily)
: Display various outputs associated with a collection of network fits -
plot(ZIPLNnetworkfamily)
: Display various outputs associated with a collection of network fits
Examples
data(trichoptera)
trichoptera <- prepare_data(trichoptera$Abundance, trichoptera$Covariate)
fits <- PLNnetwork(Abundance ~ 1, data = trichoptera)
## Not run:
plot(fits)
## End(Not run)
LDA visualization (individual and/or variable factor map(s)) for a PLNPCAfit
object
Description
LDA visualization (individual and/or variable factor map(s)) for a PLNPCAfit
object
Usage
## S3 method for class 'PLNLDAfit'
plot(
x,
map = c("both", "individual", "variable"),
nb_axes = min(3, x$rank),
axes = seq.int(min(2, x$rank)),
var_cols = "var_colors",
plot = TRUE,
main = NULL,
...
)
Arguments
x |
an R6 object with class PLNPCAfit |
map |
the type of output for the PCA visualization: either "individual", "variable" or "both". Default is "both". |
nb_axes |
scalar: the number of axes to be considered when map = "both". The default is min(3,rank). |
axes |
numeric, the axes to use for the plot when map = "individual" or "variable". Default it c(1,min(rank)) |
var_cols |
a character or factor to define the color associated with the variables. By default, all variables receive the default color of the current palette. |
plot |
logical. Should the plot be displayed or sent back as |
main |
character. A title for the single plot (individual or variable factor map). If NULL (the default), an hopefully appropriate title will be used. |
... |
Not used (S3 compatibility). |
Value
displays an individual and/or variable factor maps for the corresponding axes, and/or sends back a ggplot2::ggplot
or gtable object
Examples
data(trichoptera)
trichoptera <- prepare_data(trichoptera$Abundance, trichoptera$Covariate)
myPLNLDA <- PLNLDA(Abundance ~ 1, grouping = Group, data = trichoptera)
## Not run:
plot(myPLNLDA, map = "individual", nb_axes = 2)
## End(Not run)
Display the criteria associated with a collection of PLNPCA fits (a PLNPCAfamily)
Description
Display the criteria associated with a collection of PLNPCA fits (a PLNPCAfamily)
Usage
## S3 method for class 'PLNPCAfamily'
plot(x, criteria = c("loglik", "BIC", "ICL"), reverse = FALSE, ...)
Arguments
x |
an R6 object with class |
criteria |
vector of characters. The criteria to plot in c("loglik", "BIC", "ICL"). Default is c("loglik", "BIC", "ICL"). |
reverse |
A logical indicating whether to plot the value of the criteria in the "natural" direction (loglik - 0.5 penalty) or in the "reverse" direction (-2 loglik + penalty). Default to FALSE, i.e use the natural direction, on the same scale as the log-likelihood. |
... |
additional parameters for S3 compatibility. Not used |
Details
The BIC and ICL criteria have the form 'loglik - 1/2 * penalty'
so that they are on the same scale as the model log-likelihood. You can change this direction and use the alternate form '-2*loglik + penalty', as some authors do, by setting reverse = TRUE
.
Value
Produces a plot representing the evolution of the criteria of the different models considered, highlighting the best model in terms of BIC and ICL (see details).
Examples
data(trichoptera)
trichoptera <- prepare_data(trichoptera$Abundance, trichoptera$Covariate)
myPCAs <- PLNPCA(Abundance ~ 1 + offset(log(Offset)), data = trichoptera, ranks = 1:5)
## Not run:
plot(myPCAs)
## End(Not run)
PCA visualization (individual and/or variable factor map(s)) for a PLNPCAfit
object
Description
PCA visualization (individual and/or variable factor map(s)) for a PLNPCAfit
object
Usage
## S3 method for class 'PLNPCAfit'
plot(
x,
map = c("both", "individual", "variable"),
nb_axes = min(3, x$rank),
axes = seq.int(min(2, x$rank)),
ind_cols = "ind_colors",
var_cols = "var_colors",
plot = TRUE,
main = NULL,
...
)
Arguments
x |
an R6 object with class PLNPCAfit |
map |
the type of output for the PCA visualization: either "individual", "variable" or "both". Default is "both". |
nb_axes |
scalar: the number of axes to be considered when |
axes |
numeric, the axes to use for the plot when |
ind_cols |
a character, factor or numeric to define the color associated with the individuals. By default, all variables receive the default color of the current palette. |
var_cols |
a character, factor or numeric to define the color associated with the variables. By default, all variables receive the default color of the current palette. |
plot |
logical. Should the plot be displayed or sent back as |
main |
character. A title for the single plot (individual or variable factor map). If NULL (the default), an hopefully appropriate title will be used. |
... |
Not used (S3 compatibility). |
Value
displays an individual and/or variable factor maps for the corresponding axes, and/or sends back a ggplot2::ggplot
or gtable object
Examples
data(trichoptera)
trichoptera <- prepare_data(trichoptera$Abundance, trichoptera$Covariate)
myPCAs <- PLNPCA(Abundance ~ 1 + offset(log(Offset)), data = trichoptera, ranks = 1:5)
myPCA <- getBestModel(myPCAs)
## Not run:
plot(myPCA, map = "individual", nb_axes=2, ind_cols = trichoptera$Group)
plot(myPCA, map = "variable", nb_axes=2)
plot(myPCA, map = "both", nb_axes=2, ind_cols = trichoptera$Group)
## End(Not run)
Display the criteria associated with a collection of PLN fits (a PLNfamily)
Description
Display the criteria associated with a collection of PLN fits (a PLNfamily)
Usage
## S3 method for class 'PLNfamily'
plot(x, criteria = c("loglik", "BIC", "ICL"), reverse = FALSE, ...)
Arguments
x |
an R6 object with class |
criteria |
vector of characters. The criteria to plot in c("loglik", "BIC", "ICL"). Default is c("loglik", "BIC", "ICL"). |
reverse |
A logical indicating whether to plot the value of the criteria in the "natural" direction (loglik - 0.5 penalty) or in the "reverse" direction (-2 loglik + penalty). Default to FALSE, i.e use the natural direction, on the same scale as the log-likelihood. |
... |
additional parameters for S3 compatibility. Not used |
Details
The BIC and ICL criteria have the form 'loglik - 1/2 * penalty'
so that they are on the same scale as the model log-likelihood. You can change this direction and use the alternate form '-2*loglik + penalty', as some authors do, by setting reverse = TRUE
.
Value
Produces a plot representing the evolution of the criteria of the different models considered, highlighting the best model in terms of BIC and ICL (see details).
See Also
plot.PLNPCAfamily()
and plot.PLNnetworkfamily()
Examples
data(trichoptera)
trichoptera <- prepare_data(trichoptera$Abundance, trichoptera$Covariate)
myPCAs <- PLNPCA(Abundance ~ 1 + offset(log(Offset)), data = trichoptera, ranks = 1:5)
## Not run:
plot(myPCAs)
## End(Not run)
Display the criteria associated with a collection of PLNmixture fits (a PLNmixturefamily)
Description
Display the criteria associated with a collection of PLNmixture fits (a PLNmixturefamily)
Usage
## S3 method for class 'PLNmixturefamily'
plot(
x,
type = c("criteria", "diagnostic"),
criteria = c("loglik", "BIC", "ICL"),
reverse = FALSE,
...
)
Arguments
x |
an R6 object with class |
type |
a character, either |
criteria |
vector of characters. The criteria to plot in c("loglik", "BIC", "ICL"). Default is c("loglik", "BIC", "ICL"). |
reverse |
A logical indicating whether to plot the value of the criteria in the "natural" direction (loglik - 0.5 penalty) or in the "reverse" direction (-2 loglik + penalty). Default to FALSE, i.e use the natural direction, on the same scale as the log-likelihood. |
... |
additional parameters for S3 compatibility. Not used |
Details
The BIC and ICL criteria have the form 'loglik - 1/2 * penalty'
so that they are on the same scale as the model log-likelihood. You can change this direction and use the alternate form '-2*loglik + penalty', as some authors do, by setting reverse = TRUE
.
Value
Produces either a diagnostic plot (with type = 'diagnostic'
) or the evolution of the criteria
of the different models considered (with type = 'criteria'
, the default).
Examples
data(trichoptera)
trichoptera <- prepare_data(trichoptera$Abundance, trichoptera$Covariate)
myMixtures <- PLNmixture(Abundance ~ 1 + offset(log(Offset)),
data = trichoptera, control = PLNmixture_param(smoothing = "none"))
plot(myMixtures, reverse = TRUE)
Mixture visualization of a PLNmixturefit
object
Description
Represent the result of the clustering either by coloring the individual in a two-dimension PCA factor map, or by representing the expected matrix of count reorder according to the clustering.
Usage
## S3 method for class 'PLNmixturefit'
plot(x, type = c("pca", "matrix"), main = NULL, plot = TRUE, ...)
Arguments
x |
an R6 object with class |
type |
character for the type of plot, either "pca", for or "matrix". Default is |
main |
character. A title for the plot. If NULL (the default), an hopefully appropriate title will be used. |
plot |
logical. Should the plot be displayed or sent back as |
... |
Not used (S3 compatibility). |
Value
a ggplot2::ggplot
graphic
Examples
data(trichoptera)
trichoptera <- prepare_data(trichoptera$Abundance, trichoptera$Covariate)
myPLN <- PLNmixture(Abundance ~ 1 + offset(log(Offset)),
data = trichoptera, control = PLNmixture_param(smoothing = "none")) %>% getBestModel()
## Not run:
plot(myPLN, "pca")
plot(myPLN, "matrix")
## End(Not run)
Extract and plot the network (partial correlation, support or inverse covariance) from a PLNnetworkfit
object
Description
Extract and plot the network (partial correlation, support or inverse covariance) from a PLNnetworkfit
object
Usage
## S3 method for class 'PLNnetworkfit'
plot(
x,
type = c("partial_cor", "support"),
output = c("igraph", "corrplot"),
edge.color = c("#F8766D", "#00BFC4"),
remove.isolated = FALSE,
node.labels = NULL,
layout = layout_in_circle,
plot = TRUE,
...
)
Arguments
x |
an R6 object with class |
type |
character. Value of the weight of the edges in the network, either "partial_cor" (partial correlation) or "support" (binary). Default is |
output |
the type of output used: either 'igraph' or 'corrplot'. Default is |
edge.color |
Length 2 color vector. Color for positive/negative edges. Default is |
remove.isolated |
if |
node.labels |
vector of character. The labels of the nodes. The default will use the column names ot the response matrix. |
layout |
an optional igraph layout. Only relevant for igraph output. |
plot |
logical. Should the final network be displayed or only sent back to the user. Default is |
... |
Not used (S3 compatibility). |
Value
Send back an invisible object (igraph or Matrix, depending on the output chosen) and optionally displays a graph (via igraph or corrplot for large ones)
Examples
data(trichoptera)
trichoptera <- prepare_data(trichoptera$Abundance, trichoptera$Covariate)
fits <- PLNnetwork(Abundance ~ 1, data = trichoptera)
myNet <- getBestModel(fits)
## Not run:
plot(myNet)
## End(Not run)
Extract and plot the network (partial correlation, support or inverse covariance) from a ZIPLNfit_sparse
object
Description
Extract and plot the network (partial correlation, support or inverse covariance) from a ZIPLNfit_sparse
object
Usage
## S3 method for class 'ZIPLNfit_sparse'
plot(
x,
type = c("partial_cor", "support"),
output = c("igraph", "corrplot"),
edge.color = c("#F8766D", "#00BFC4"),
remove.isolated = FALSE,
node.labels = NULL,
layout = layout_in_circle,
plot = TRUE,
...
)
Arguments
x |
an R6 object with class |
type |
character. Value of the weight of the edges in the network, either "partial_cor" (partial correlation) or "support" (binary). Default is |
output |
the type of output used: either 'igraph' or 'corrplot'. Default is |
edge.color |
Length 2 color vector. Color for positive/negative edges. Default is |
remove.isolated |
if |
node.labels |
vector of character. The labels of the nodes. The default will use the column names ot the response matrix. |
layout |
an optional igraph layout. Only relevant for igraph output. |
plot |
logical. Should the final network be displayed or only sent back to the user. Default is |
... |
Not used (S3 compatibility). |
Value
Send back an invisible object (igraph or Matrix, depending on the output chosen) and optionally displays a graph (via igraph or corrplot for large ones)
Examples
data(trichoptera)
trichoptera <- prepare_data(trichoptera$Abundance, trichoptera$Covariate)
fit <- ZIPLN(Abundance ~ 1, data = trichoptera, control = ZIPLN_param(penalty = 0.1))
## Not run:
plot(fit)
## End(Not run)
Predict group of new samples
Description
Predict group of new samples
Usage
## S3 method for class 'PLNLDAfit'
predict(
object,
newdata,
type = c("posterior", "response", "scores"),
scale = c("log", "prob"),
prior = NULL,
control = PLN_param(backend = "nlopt"),
...
)
Arguments
object |
an R6 object with class |
newdata |
A data frame in which to look for variables, offsets and counts with which to predict. |
type |
The type of prediction required. The default are posterior probabilities for each group (in either unnormalized log-scale or natural probabilities, see "scale" for details), "response" is the group with maximal posterior probability and "scores" is the average score along each separation axis in the latent space, with weights equal to the posterior probabilities. |
scale |
The scale used for the posterior probability. Either log-scale ("log", default) or natural probabilities summing up to 1 ("prob"). |
prior |
User-specified prior group probabilities in the new data. If NULL (default), prior probabilities are computed from the learning set. |
control |
a list for controlling the optimization. See |
... |
additional parameters for S3 compatibility. Not used |
Value
A matrix of posterior probabilities for each group (if type = "posterior"), a matrix of (average) scores in the latent space (if type = "scores") or a vector of predicted groups (if type = "response").
Examples
data(trichoptera)
trichoptera <- prepare_data(trichoptera$Abundance, trichoptera$Covariate)
myLDA <- PLNLDA(Abundance ~ 0 + offset(log(Offset)),
grouping = Group,
data = trichoptera)
## Not run:
post_probs <- predict(myLDA, newdata = trichoptera, type = "posterior", scale = "prob")
head(round(post_probs, digits = 3))
predicted_group <- predict(myLDA, newdata = trichoptera, type = "response")
table(predicted_group, trichoptera$Group, dnn = c("predicted", "true"))
## End(Not run)
Predict counts of a new sample
Description
Predict counts of a new sample
Usage
## S3 method for class 'PLNfit'
predict(
object,
newdata,
responses = NULL,
level = 1,
type = c("link", "response"),
...
)
Arguments
object |
an R6 object with class |
newdata |
A data frame in which to look for variables and offsets with which to predict |
responses |
Optional data frame containing the count of the observed variables (matching the names of the provided as data in the PLN function), assuming the interest in in testing the model. |
level |
Optional integer value the level to be used in obtaining the predictions. Level zero corresponds to the population predictions (default if |
type |
The type of prediction required. The default is on the scale of the linear predictors (i.e. log average count) |
... |
additional parameters for S3 compatibility. Not used |
Value
A matrix of predicted log-counts (if type = "link"
) or predicted counts (if type = "response"
).
Prediction for a PLNmixturefit
object
Description
Predict either posterior probabilities for each group or latent positions based on new samples
Usage
## S3 method for class 'PLNmixturefit'
predict(
object,
newdata,
type = c("posterior", "response", "position"),
prior = matrix(rep(1/object$k, object$k), nrow(newdata), object$k, byrow = TRUE),
control = PLNmixture_param(),
...
)
Arguments
object |
an R6 object with class |
newdata |
A data frame in which to look for variables, offsets and counts with which to predict. |
type |
The type of prediction required. The default |
prior |
User-specified prior group probabilities in the new data. The default uses a uniform prior. |
control |
a list-like structure for controlling the fit. See |
... |
additional parameters for S3 compatibility. Not used |
Value
A matrix of posterior probabilities for each group (if type = "posterior"), a matrix of (average) position in the latent space (if type = "position") or a vector of predicted groups (if type = "response").
Examples
data(trichoptera)
trichoptera <- prepare_data(trichoptera$Abundance, trichoptera$Covariate)
myPLN <- PLNmixture(Abundance ~ 1 + offset(log(Offset)),
data = trichoptera, control = PLNmixture_param(smoothing = "none")) %>% getBestModel()
predict(myPLN, trichoptera, "posterior")
predict(myPLN, trichoptera, "position")
predict(myPLN, trichoptera, "response")
Predict counts of a new sample
Description
Predict counts of a new sample
Usage
## S3 method for class 'ZIPLNfit'
predict(
object,
newdata,
responses = NULL,
level = 1,
type = c("link", "response", "deflated"),
...
)
Arguments
object |
an R6 object with class |
newdata |
A data frame in which to look for variables and offsets with which to predict |
responses |
Optional data frame containing the count of the observed variables (matching the names of the provided as data in the PLN function), assuming the interest in in testing the model. |
level |
Optional integer value the level to be used in obtaining the predictions. Level zero corresponds to the population predictions (default if |
type |
Scale used for the prediction. Either |
... |
additional parameters for S3 compatibility. Not used |
Details
Note that level = 1
can only be used if responses are provided,
as the variational parameters can't be estimated otherwise. In the absence of responses, level
is ignored and the fitted values are returned
Note also that when type = "response"
corresponds to predicting
values with (1 - \pi)A
, where A
is the average count in
the PLN part of the model and \pi
the probability of zero-inflation,
whereas type = "deflated"
corresponds to A
.
Predict counts conditionally
Description
Predict counts of a new sample conditionally on a (set of) observed variables
Usage
predict_cond(
object,
newdata,
cond_responses,
type = c("link", "response"),
var_par = FALSE
)
## S3 method for class 'PLNfit'
predict_cond(
object,
newdata,
cond_responses,
type = c("link", "response"),
var_par = FALSE
)
Arguments
object |
an R6 object with class |
newdata |
A data frame in which to look for variables and offsets with which to predict |
cond_responses |
a data frame containing the counts of the observed variables (matching the names provided as data in the PLN function) |
type |
The type of prediction required. The default is on the scale of the linear predictors (i.e. log average count) |
var_par |
Boolean. Should new estimations of the variational parameters of mean and variance be sent back, as attributes of the matrix of predictions. Default to |
Value
A list containing:
pred |
A matrix of predicted log-counts (if |
M |
A matrix containing E(Z_uncond | Y_c) for each given site. |
S |
A matrix containing Var(Z_uncond | Y_c) for each given site (sites are the third dimension of the array) |
Methods (by class)
-
predict_cond(PLNfit)
: Predict counts of a new sample conditionally on a (set of) observed variables for aPLNfit
Examples
data(trichoptera)
trichoptera_prep <- prepare_data(trichoptera$Abundance, trichoptera$Covariate)
myPLN <- PLN(Abundance ~ Temperature + Wind, trichoptera_prep)
#Condition on the set of the first two species in the dataset (Hym, Hys) at the ten first sites
Yc <- trichoptera$Abundance[1:10, c(1, 2), drop=FALSE]
newX <- cbind(1, trichoptera$Covariate[1:10, c("Temperature", "Wind")])
pred <- predict_cond(myPLN, newX, Yc, type = "response")
Prepare data for use in PLN models
Description
Prepare data in proper format for use in PLN model and its variants. The function (i) merges a count table and a covariate data frame in the most comprehensive way and (ii) computes offsets from the count table using one of several normalization schemes (TSS, CSS, RLE, GMPR, Wrench, etc). The function fails with informative messages when the heuristics used for sample matching fail.
Usage
prepare_data(
counts,
covariates,
offset = "TSS",
call = rlang::caller_env(),
...
)
Arguments
counts |
Required. An abundance count table, preferably with dimensions names and species as columns. |
covariates |
Required. A covariates data frame, preferably with row names. |
offset |
Optional. Normalization scheme used to compute scaling factors used as offset during PLN inference. Available schemes are "TSS" (Total Sum Scaling, default), "CSS" (Cumulative Sum Scaling, used in metagenomeSeq), "RLE" (Relative Log Expression, used in DESeq2), "GMPR" (Geometric Mean of Pairwise Ratio, introduced in Chen et al., 2018), Wrench (introduced in Kumar et al., 2018) or "none". Alternatively the user can supply its own vector or matrix of offsets (see note for specification of the user-supplied offsets). |
call |
Optional. The execution environment in which to set the local error call. |
... |
Additional parameters passed on to |
Value
A data.frame suited for use in PLN()
and its variants with two specials components: an abundance count matrix (in component "Abundance") and an offset vector/matrix (in component "Offset", only if offset is not set to "none")
Note
User supplied offsets should be either vectors/column-matrices or have the same number of column as the original count matrix and either (i) dimension names or (ii) the same dimensions as the count matrix. Samples are trimmed in exactly the same way to remove empty samples.
References
Chen, L., Reeve, J., Zhang, L., Huang, S., Wang, X. and Chen, J. (2018) GMPR: A robust normalization method for zero-inflated count data with application to microbiome sequencing data. PeerJ, 6, e4600 doi:10.7717/peerj.4600
Paulson, J. N., Colin Stine, O., Bravo, H. C. and Pop, M. (2013) Differential abundance analysis for microbial marker-gene surveys. Nature Methods, 10, 1200-1202 doi:10.1038/nmeth.2658
Anders, S. and Huber, W. (2010) Differential expression analysis for sequence count data. Genome Biology, 11, R106 doi:10.1186/gb-2010-11-10-r106
Kumar, M., Slud, E., Okrah, K. et al. (2018) Analysis and correction of compositional bias in sparse sequencing count data. BMC Genomics 19, 799 doi:10.1186/s12864-018-5160-5
Robinson, M.D., Oshlack, A. (2010) A scaling normalization method for differential expression analysis of RNA-seq data. Genome Biol 11, R25 doi:10.1186/gb-2010-11-3-r25
See Also
compute_offset()
for details on the different normalization schemes
Examples
data(trichoptera)
proper_data <- prepare_data(
counts = trichoptera$Abundance,
covariates = trichoptera$Covariate,
offset = "GMPR",
scale = "count"
)
proper_data$Abundance
proper_data$Offset
PLN RNG
Description
Random generation for the PLN model with latent mean equal to mu, latent covariance matrix equal to Sigma and average depths (sum of counts in a sample) equal to depths
Usage
rPLN(
n = 10,
mu = rep(0, ncol(Sigma)),
Sigma = diag(1, 5, 5),
depths = rep(10000, n)
)
Arguments
n |
the sample size |
mu |
vectors of means of the latent variable |
Sigma |
covariance matrix of the latent variable |
depths |
Numeric vector of target depths. The first is recycled if there are not |
Details
The default value for mu and Sigma assume equal abundances and no correlation between the different species.
Value
a n * p count matrix, with row-sums close to depths, with an attribute "offsets" corresponding to the true generated offsets (in log-scale).
Examples
## 10 samples of 5 species with equal abundances, no covariance and target depths of 10,000
rPLN()
## 2 samples of 10 highly correlated species with target depths 1,000 and 100,000
## very different abundances
mu <- rep(c(1, -1), each = 5)
Sigma <- matrix(0.8, 10, 10); diag(Sigma) <- 1
rPLN(n=2, mu = mu, Sigma = Sigma, depths = c(1e3, 1e5))
Single cell RNA-seq data
Description
A dataset containing the counts of the 500 most varying transcripts in the mixtures of 5 cell lines in human liver (obtained with standard 10x scRNAseq Chromium protocol).
Usage
scRNA
Format
A data frame named 'scRNA' with 3918 rows (the cells) and 3 variables:
- counts
a 500 trancript by 3918 count matrix
- cell_line
factor, the cell line of the current row (among 5)
- total_counts
Total number of reads for that cell
...
Source
https://github.com/LuyiTian/sc_mixology/
Extract variance-covariance of residuals 'Sigma'
Description
Extract the variance-covariance matrix of the residuals, usually noted
\Sigma
in PLN models. This captures the correlation between the species in the latent space.
Usage
## S3 method for class 'PLNfit'
sigma(object, ...)
Arguments
object |
an R6 object with class |
... |
additional parameters for S3 compatibility. Not used |
Value
A semi definite positive matrix of size p, assuming there are p species in the model.
See Also
coef.PLNfit()
, standard_error.PLNfit()
and vcov.PLNfit()
for other ways to access
\Sigma
.
Examples
data(trichoptera)
trichoptera <- prepare_data(trichoptera$Abundance, trichoptera$Covariate)
myPLN <- PLN(Abundance ~ 1 + offset(log(Offset)), data = trichoptera)
sigma(myPLN) ## Sigma
Extract variance-covariance of residuals 'Sigma'
Description
Extract the variance-covariance matrix of the residuals, usually noted
\Sigma
in PLN models. This captures the correlation between the species in the latent space. or PLNmixture, it is a weighted mean of the variance-covariance matrices of each component.
Usage
## S3 method for class 'PLNmixturefit'
sigma(object, ...)
Arguments
object |
an R6 object with class |
... |
additional parameters for S3 compatibility. Not used |
Value
A semi definite positive matrix of size p, assuming there are p species in the model.
See Also
coef.PLNmixturefit()
for other ways to access
\Sigma
.
Examples
data(trichoptera)
trichoptera <- prepare_data(trichoptera$Abundance, trichoptera$Covariate)
myPLN <- PLNmixture(Abundance ~ 1 + offset(log(Offset)),
data = trichoptera, control = PLNmixture_param(smoothing = "none")) %>% getBestModel()
sigma(myPLN) ## Sigma
Extract variance-covariance of residuals 'Sigma'
Description
Extract the variance-covariance matrix of the residuals, usually noted \Sigma
in ZIPLN models.
Usage
## S3 method for class 'ZIPLNfit'
sigma(object, ...)
Arguments
object |
an R6 object with class |
... |
additional parameters for S3 compatibility. Not used |
Value
A semi definite positive matrix of size p, assuming there are p species in the model.
See Also
Compute the stability path by stability selection
Description
This function computes the StARS stability criteria over a path of penalties. If a path has already been computed, the functions stops with a message unless force = TRUE
has been specified.
Usage
stability_selection(
Robject,
subsamples = NULL,
control = PLNnetwork_param(),
force = FALSE
)
Arguments
Robject |
an object with class |
subsamples |
a list of vectors describing the subsamples. The number of vectors (or list length) determines th number of subsamples used in the stability selection. Automatically set to 20 subsamples with size |
control |
a list controlling the main optimization process in each call to |
force |
force computation of the stability path, even if a previous one has been detected. |
Value
the list of subsamples. The estimated probabilities of selection of the edges are stored in the fields stability_path
of the initial Robject with class Networkfamily
Examples
data(trichoptera)
trichoptera <- prepare_data(trichoptera$Abundance, trichoptera$Covariate)
fits <- PLNnetwork(Abundance ~ 1, data = trichoptera)
## Not run:
n <- nrow(trichoptera)
subs <- replicate(10, sample.int(n, size = n/2), simplify = FALSE)
stability_selection(nets, subsamples = subs)
## End(Not run)
Component-wise standard errors of B
Description
Extracts univariate standard errors for the estimated coefficient of B. Standard errors are computed from the (approximate) Fisher information matrix.
Usage
## S3 method for class 'PLNPCAfit'
standard_error(
object,
type = c("variational", "jackknife", "sandwich"),
parameter = c("B", "Omega")
)
standard_error(
object,
type = c("sandwich", "variational", "jackknife"),
parameter = c("B", "Omega")
)
## S3 method for class 'PLNfit'
standard_error(
object,
type = c("sandwich", "variational", "jackknife", "bootstrap"),
parameter = c("B", "Omega")
)
## S3 method for class 'PLNfit_fixedcov'
standard_error(
object,
type = c("sandwich", "variational", "jackknife", "bootstrap"),
parameter = c("B", "Omega")
)
## S3 method for class 'PLNmixturefit'
standard_error(
object,
type = c("variational", "jackknife", "sandwich"),
parameter = c("B", "Omega")
)
## S3 method for class 'PLNnetworkfit'
standard_error(
object,
type = c("variational", "jackknife", "sandwich"),
parameter = c("B", "Omega")
)
Arguments
object |
an R6 object with class PLNfit |
type |
string describing the type of variance approximation: "variational", "jackknife", "sandwich". Default is "sandwich". |
parameter |
string describing the target parameter: either B (regression coefficients) or Omega (inverse residual covariance) |
Value
A p * d positive matrix (same size as B
) with standard errors for the coefficients of B
Methods (by class)
-
standard_error(PLNPCAfit)
: Component-wise standard errors of B inPLNPCAfit
(not implemented yet) -
standard_error(PLNfit)
: Component-wise standard errors of B inPLNfit
-
standard_error(PLNfit_fixedcov)
: Component-wise standard errors of B inPLNfit_fixedcov
-
standard_error(PLNmixturefit)
: Component-wise standard errors of B inPLNmixturefit
(not implemented yet) -
standard_error(PLNnetworkfit)
: Component-wise standard errors of B inPLNnetworkfit
(not implemented yet)
See Also
vcov.PLNfit()
for the complete variance covariance estimation of the coefficient
Examples
data(trichoptera)
trichoptera <- prepare_data(trichoptera$Abundance, trichoptera$Covariate)
myPLN <- PLN(Abundance ~ 1 + offset(log(Offset)), data = trichoptera,
control = PLN_param(config_post = list(sandwich_var = TRUE)))
standard_error(myPLN)
Trichoptera data set
Description
Data gathered between 1959 and 1960 during 49 insect trapping nights. For each trapping night, the abundance of 17 Trichoptera species is recorded as well as 6 meteorological variables which may influence the abundance of each species. Finally, the observations (that is to say, the trapping nights), have been classified into 12 groups corresponding to contiguous nights between summer 1959 and summer 1960.
Usage
trichoptera
Format
A list with 2 two data frames:
- Abundance
a 49 x 17 matrix of abundancies/counts (49 trapping nights and 17 trichoptera species)
- Covariate
a 49 x 7 data frame of covariates:
- Temperature
Evening Temperature in Celsius
- Wind
Wind in m/s
- Pressure
Pressure in mm Hg
- Humidity
relative to evening humidity in percent
- Cloudiness
proportion of sky coverage at 9pm
- Precipitation
Nighttime precipitation in mm
- Group
a factor of 12 levels for the definition of the consecutive night groups
In order to prepare the data for using formula in multivariate analysis (multiple outputs and inputs), use prepare_data()
.
We only kept a subset of the original meteorological covariates for illustration purposes.
Source
Data from P. Usseglio-Polatera.
References
Usseglio-Polatera, P. and Auda, Y. (1987) Influence des facteurs météorologiques sur les résultats de piégeage lumineux. Annales de Limnologie, 23, 65–79. (code des espèces p. 76) See a data description at http://pbil.univ-lyon1.fr/R/pdf/pps034.pdf (in French)
See Also
Examples
data(trichoptera)
trichoptera <- prepare_data(trichoptera$Abundance, trichoptera$Covariate)
Calculate Variance-Covariance Matrix for a fitted PLN()
model object
Description
Returns the variance-covariance matrix of the main parameters of a fitted PLN()
model object. The main parameters of the model correspond to
B
, as returned by coef.PLNfit()
. The function can also be used to return the variance-covariance matrix of the residuals. The latter matrix can also be accessed via sigma.PLNfit()
Usage
## S3 method for class 'PLNfit'
vcov(object, type = c("main", "covariance"), ...)
Arguments
object |
an R6 object with class |
type |
type of parameter that should be extracted. Either "main" (default) for
or "covariance" for
|
... |
additional parameters for S3 compatibility. Not used |
Value
A matrix of variance/covariance extracted from the PLNfit model. If type="main" and B
is a matrix of size d * p, the result is a block-diagonal matrix with p (number of species) blocks of size d (number of covariates). if type="main", it is a symmetric matrix of size p.
.
See Also
sigma.PLNfit()
, coef.PLNfit()
, standard_error.PLNfit()
Examples
data(trichoptera)
trichoptera <- prepare_data(trichoptera$Abundance, trichoptera$Covariate)
myPLN <- PLN(Abundance ~ 1 + offset(log(Offset)), data = trichoptera)
vcov(myPLN, type = "covariance") ## Sigma