| Type: | Package |
| Title: | An R Package to Extend 'ACER ConQuest' |
| Version: | 1.5.1 |
| Description: | Extends 'ACER ConQuest' through a family of functions designed to improve graphical outputs and help with advanced analysis (e.g., differential item functioning). Allows R users to call 'ACER ConQuest' from within R and read 'ACER ConQuest' System Files (generated by the command ‘put' https://conquestmanual.acer.org/s4-00.html#put). Requires ’ACER ConQuest' version 5.40 or later. A demonstration version can be downloaded from https://shop.acer.org/acer-conquest-5.html. |
| License: | GPL-3 |
| URL: | https://www.acer.org/au/conquest, https://conquestmanual.acer.org, https://shop.acer.org/acer-conquest-5.html |
| Imports: | dplyr, ggplot2 (≥ 3.5.1), ggrepel, kableExtra, magrittr, methods, Rcpp, rlang, stats, stringr, tidyr, tidyselect, zlib |
| Suggests: | knitr, gridExtra, rmarkdown, testthat (≥ 3.2.1) |
| LinkingTo: | Rcpp |
| VignetteBuilder: | knitr |
| Config/testthat/edition: | 3 |
| Encoding: | UTF-8 |
| RoxygenNote: | 7.3.2 |
| SystemRequirements: | ACER ConQuest (>=5.40.0) |
| Collate: | "RcppExports.R" "ReadConQuestLibrary.R" "ReadConQuestRout_createDF.R" "ReadConQuestState.R" "postProcessCqSysfile.R" "ReadConQuestState_createDF.R" "conquestr.R" "conquestrFunc.R" "generateItems.R" "generateHelpers.R" "infoHelpers.R" "itanalHelpers.R" "plotGeneral.R" "plotRout.R" "pvHelpers.R" "residHelpers.R" "showHelpers.R" "thrstThrsh.R" "cleaningHelpers.R" |
| Depends: | R (≥ 4.1.0) |
| NeedsCompilation: | yes |
| Packaged: | 2025-05-18 07:26:21 UTC; acercloneyd |
| Author: | Dan Cloney  [aut,
cre],
Ray Adams [aut] |
| Maintainer: | Dan Cloney <dan.cloney@acer.org> |
| Repository: | CRAN |
| Date/Publication: | 2025-05-18 07:50:02 UTC |
ConQuestCall
Description
Call an instance of 'ACER ConQuest' at the command line and run a control file (syntax).
Usage
ConQuestCall(cqc, cqExe, stdout = "")
Arguments
cqc |
The location of the control file (syntax) to be run. |
cqExe |
The path to the 'ACER ConQuest' executable. Note, if this argument is missing, conquestr will find a local installation of ACER ConQuest by first searching the default installation locations (Program Files on Windows and Applications on Mac) then searching other local directories (Appdata and the HOME path). |
stdout |
On Mac only, can be toggled to NULL (or a connection) to suppress output to R console. |
Value
prints 'ACER ConQuest' output to stdout.
Examples
## Not run:
ConQuestCall()
## End(Not run)
ConQuestRout
Description
Read an 'ACER ConQuest' rout file (a binary file)
created by a plot
command in 'ACER ConQuest'.
Usage
ConQuestRout(myRout)
Arguments
myRout |
The path to the binary rout file. |
Value
A list containing the data objects to recreate 'ACER ConQuest' plots.
Examples
myPlot <- ConQuestRout()
## Not run:
# the default example is an ICC plot from Example 1
# <https://conquestmanual.acer.org/s2-00.html#s2-02>.
str(myPlot)
## End(Not run)
ConQuestSys
Description
Read an ”ACER ConQuest” system file created by a put command in 'ACER ConQuest'.
The system file must not be compressed. Use the option ‘compressed=no“ in the put command within ’ACER ConQuest'.
Usage
ConQuestSys(myCqs, isMini = FALSE)
Arguments
myCqs |
The location of an uncompressed 'ACER ConQuest' system file created by 'ACER ConQuest' > 4.35. |
isMini |
A boolean, set to TRUE if the system file is a mini system file created by 'ACER ConQuest' command put with option "mini = yes". |
Value
A list containing the data objects created by 'ACER ConQuest'.
Examples
mySysData <- ConQuestSys()
myEx1SysData <- ConQuestSys(myCqs = system.file("extdata", "mysysfile.cqs", package = "conquestr"))
## Not run:
# if you run the above example this will return your original 'ACER ConQuest' syntax.
cat(unlist(myEx1SysData$gCommandHistory))
## End(Not run)
DecompressSys
Description
Internal function to decompress an 'ACER ConQuest' system file that has been compressed using zlib.
Usage
DecompressSys(myFile)
Arguments
myFile |
An connection to a compressed 'ACER ConQuest' system file
created by the |
Value
A connection to an uncompressed system file in the users temp dir.
See Also
conquestr::ConQuestSys()
ItemDfStdZ
Description
Calculates centred and scaled item parameter estimates. Also calculates standardised standard errors of item parameter estimates to complement scaled item parameter estimates.
Usage
ItemDfStdZ(myDf)
Arguments
myDf |
a data frame. |
Value
a data frame.
See Also
conquestr::sysToItemDifDf()
ItemDfStdZMerge
Description
Calculates Z test on the common items from 2 data frames
returned from conquestr::ItemDfStdZ.
Usage
ItemDfStdZMerge(myDf1, myDf2, mySuffixes)
Arguments
myDf1 |
a data frame. |
myDf2 |
a data frame. |
mySuffixes |
a vector of strings specifying the names for the two
groups being analysed, e.g., if the two system files are an analysis of boys and girls, the vector may be |
Value
a data frame.
See Also
conquestr::sysToItemDifDf()
ReadADesignMatrices
Description
ReadSys Read the A design matrix (A list of length gNGins of matrices. For each matrix the number of rows is gItemSteps (for that item) and the number of columns is gNParameters_C).
Usage
ReadADesignMatrices(myFile, Columns, Items, ItemSteps)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Columns |
An integer representation of 'ACER ConQuest' object gNParameters. |
Items |
An integer representation of 'ACER ConQuest' object gNGins. |
ItemSteps |
An integer representation of 'ACER ConQuest' object gItemSteps. |
Value
A list
ReadAllCaseEstimates
Description
ReadAllCaseEstimates
Usage
ReadAllCaseEstimates(myFile, Dimensions, N, NPlausibles)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Dimensions |
An integer representation of 'ACER ConQuest' object gNDim. |
N |
An integer representation of 'ACER ConQuest' object gNCases |
NPlausibles |
An integer representation of 'ACER ConQuest' object gNPlausibles. |
Value
A list
ReadAllGroupsData
Description
ReadAllGroupsData
Usage
ReadAllGroupsData(myFile, N, GroupVariables, AllVariables)
Arguments
myFile |
An 'ACER ConQuest' system file. |
N |
An integer representation of 'ACER ConQuest' object gNCases. |
GroupVariables |
A list of group variables. |
AllVariables |
A list of variables. |
Value
A list
ReadAllResponseData
Description
ReadAllResponseData
Usage
ReadAllResponseData(myFile, N)
Arguments
myFile |
An 'ACER ConQuest' system file. |
N |
An integer representation of 'ACER ConQuest' object gNCases. |
Value
A list
ReadAllY
Description
ReadAllY
Usage
ReadAllY(myFile, N, NReg)
Arguments
myFile |
An 'ACER ConQuest' system file. |
N |
An integer representation of 'ACER ConQuest' object gNCases |
NReg |
An integer representing the number of regressors in the model, a representation of 'ACER ConQuest' object gNReg. |
ReadAnchor
Description
ReadAnchor
Usage
ReadAnchor(myFile)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A list
ReadAnchorList
Description
ReadAnchorList
Usage
ReadAnchorList(myFile)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A list
ReadBDesignMatrices
Description
ReadSys Read the B design matrix (A list of length gNGins of lists, one per item. For each item a list of length gItemSteps of matrices).
Usage
ReadBDesignMatrices(myFile, ItemSteps, Items)
Arguments
myFile |
An 'ACER ConQuest' system file. |
ItemSteps |
An integer representation of 'ACER ConQuest' object gItemSteps. |
Items |
An integer representation of 'ACER ConQuest' object gNGins. |
Value
A list
ReadBandDefine
Description
ReadBandDefine
Usage
ReadBandDefine(myFile)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A list
ReadBandDefinesList
Description
ReadBandDefinesList
Usage
ReadBandDefinesList(myFile)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A list
ReadBitSet
Description
ReadBitSet
Usage
ReadBitSet(myFile)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A list
ReadBoolean
Description
ReadBoolean
Usage
ReadBoolean(myFile)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A list
ReadBooleanList
Description
ReadBooleanList
Usage
ReadBooleanList(myFile)
Arguments
myFile |
An uncompress 'ACER ConQuest' system file created by 'ACER ConQuest'. |
Value
A list
ReadCDesignMatrices
Description
ReadSys Read the C design matrix (A list of length gNGins of lists, one per item. For each item a list of length gItemSteps of matrices).
Usage
ReadCDesignMatrices(myFile, Dimensions, ItemSteps, Items)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Dimensions |
An integer representation of 'ACER ConQuest' object gNDim. |
ItemSteps |
An integer representation of 'ACER ConQuest' object gItemSteps. |
Items |
An integer representation of 'ACER ConQuest' object gNGins. |
Value
A list
ReadCategorise
Description
ReadCategorise
Usage
ReadCategorise(myFile)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A list
ReadCategoriseLegacy
Description
ReadCategoriseLegacy
Usage
ReadCategoriseLegacy(myFile)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A list
ReadCategoriseList
Description
ReadCategoriseList
Usage
ReadCategoriseList(myFile)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A list
ReadCategoriseListLegacy
Description
ReadCategoriseListLegacy
Usage
ReadCategoriseListLegacy(myFile)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A list
ReadCodeList
Description
ReadCodeList
Usage
ReadCodeList(myFile)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A list
ReadDataRecord
Description
ReadDataRecord
Usage
ReadDataRecord(myFile)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A list
ReadDouble
Description
ReadDouble
Usage
ReadDouble(myFile)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A list
ReadDoubleList
Description
ReadDoubleList
Usage
ReadDoubleList(myFile)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A list
ReadErrors
Description
ReadErrors
Usage
ReadErrors(myFile)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A list
ReadEstimatesRecord
Description
ReadEstimatesRecord
Usage
ReadEstimatesRecord(myFile, Dimensions, NPlausibles, n)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Dimensions |
An integer representation of 'ACER ConQuest' object gNDim. |
NPlausibles |
An integer representation of 'ACER ConQuest' object gNPlausibles. |
n |
An integer representation of 'ACER ConQuest' object gNCases. |
Value
A list
ReadFit
Description
ReadFit
Usage
ReadFit(myFile)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A list
ReadFitList
Description
ReadFitList
Usage
ReadFitList(myFile)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A list
ReadGExportOptions
Description
ReadGExportOptions
Usage
ReadGExportOptions(myFile)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A list of a single ExportOption (e.g., used in ExportXsi())
ReadGExportOptionsList
Description
ReadGExportOptionsList
Usage
ReadGExportOptionsList(myFile)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A list of ExportOptions
ReadGraph
Description
ReadGraph
Usage
ReadGraph(myFile)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A list
ReadGroupsOneCase
Description
ReadGroupsOneCase
Usage
ReadGroupsOneCase(myFile, GroupVariables, AllVariables, CaseNum)
Arguments
myFile |
An 'ACER ConQuest' system file. |
GroupVariables |
A list of group variables for this case. |
AllVariables |
A list of variables for this case. |
CaseNum |
An integer representing the case number used in the lookup tables. |
Value
A list
ReadHistory
Description
ReadHistory
Usage
ReadHistory(myFile)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A list
ReadIRecode
Description
ReadIRecode
Usage
ReadIRecode(myFile)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A list
ReadIRecodeList
Description
ReadIRecodeList
Usage
ReadIRecodeList(myFile)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A list
ReadImplicitVar
Description
ReadImplicitVar
Usage
ReadImplicitVar(myFile)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A list
ReadIntArray2
Description
ReadIntArray2
Usage
ReadIntArray2(myFile)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A matrix
ReadInteger
Description
ReadInteger
Usage
ReadInteger(myFile)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A list
ReadIntegerList
Description
ReadIntegerList
Usage
ReadIntegerList(myFile)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A list
ReadIntegerListList
Description
ReadIntegerListList
Usage
ReadIntegerListList(myFile)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A list
ReadItemSet
Description
ReadItemSet
Usage
ReadItemSet(myFile)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A list
ReadItemSetList
Description
ReadItemSetList
Usage
ReadItemSetList(myFile)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A list
ReadKey
Description
ReadKey
Usage
ReadKey(myFile)
ReadKeyList
Description
ReadKeyList
Usage
ReadKeyList(myFile)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A list
ReadLabel
Description
ReadLabel
Usage
ReadLabel(myFile)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A list
ReadLabelList
Description
ReadLabelList
Usage
ReadLabelList(myFile)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A list
ReadLookUp
Description
ReadLookUp
Usage
ReadLookUp(myFile)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A list
ReadLookUpList
Description
ReadLookUpList
Usage
ReadLookUpList(myFile)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A list
ReadMatrix
Description
ReadMatrix
Usage
ReadMatrix(myFile)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A list
ReadMatrixList
Description
ReadMatrixList
Usage
ReadMatrixList(myFile)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A list
ReadMatrixVars
Description
ReadMatrixVars
Usage
ReadMatrixVars(myFile)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A list
ReadNamedStringList
Description
ReadNamedStringList
Usage
ReadNamedStringList(myFile)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A data frame
ReadParameters
Description
ReadParameters
Usage
ReadParameters(myFile)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A list
ReadParametersList
Description
ReadParametersList
Usage
ReadParametersList(myFile)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A list
ReadPoint
Description
ReadPoint
Usage
ReadPoint(myFile)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A list
ReadRandomStructure
Description
ReadRandomStructure
Usage
ReadRandomStructure(myFile)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A list
ReadRegression
Description
ReadRegression
Usage
ReadRegression(myFile)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A list
ReadRegressionList
Description
ReadRegressionList
Usage
ReadRegressionList(myFile)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A list
ReadRegressionListLeg
Description
ReadRegressionListLeg
Usage
ReadRegressionListLeg(myFile)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A list
ReadRegressors
Description
ReadRegressors
Usage
ReadRegressors(myFile)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A list
ReadResponse
Description
ReadResponse
Usage
ReadResponse(myFile)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A list
ReadResponseList
Description
ReadResponseList
Usage
ReadResponseList(myFile)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A list
ReadSeries
Description
ReadSeries
Usage
ReadSeries(myFile)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A list
ReadString
Description
ReadString
Usage
ReadString(myFile)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A list
ReadStringList
Description
ReadStringList
Usage
ReadStringList(myFile)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A list
ReadSys
Description
Internal function to read an 'ACER ConQuest' system file. Called by conquestr::ConQuestSys.
Usage
ReadSys(myFile, isMini)
Arguments
myFile |
An connection to an 'ACER ConQuest' system file created by the
|
isMini |
A boolean, set to TRUE if the system file is a mini system file created by 'ACER ConQuest' command put with option "mini = yes". |
Value
A list containing the data objects created by 'ACER ConQuest'.
See Also
conquestr::ConQuestSys()
ReadSysMini
Description
Internal function to read an 'ACER ConQuest' system file. Called by conquestr::ConQuestSys.
Usage
ReadSysMini(myFile, Dimensions, N, NPlausibles, isDebug)
Arguments
myFile |
An 'ACER ConQuest' mini system file created by the |
Dimensions |
. |
N |
. |
NPlausibles |
. |
isDebug |
. |
Value
A list containing the data objects created by 'ACER ConQuest'.
See Also
conquestr::ConQuestSys()
ReadTerm
Description
ReadTerm
Usage
ReadTerm(myFile)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A list
ReadTerms
Description
ReadTerms
Usage
ReadTerms(myFile, cqs_version)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A list
ReadTermsList
Description
ReadTermsList
ReadTermsList
Usage
ReadTermsList(myFile, cqs_version)
ReadTermsList(myFile, cqs_version)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A list
A list
ReadVarInfo
Description
ReadVarInfo
Usage
ReadVarInfo(myFile)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A list
ReadVarList
Description
ReadVarList
Usage
ReadVarList(myFile)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A list
ReadVariable
Description
ReadVariable
Usage
ReadVariable(myFile)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A list
ReadVariableList
Description
ReadVariableList
Usage
ReadVariableList(myFile)
Arguments
myFile |
An 'ACER ConQuest' system file. |
Value
A list
ReadYOneCase
Description
ReadYOneCase
Usage
ReadYOneCase(myFile, NReg)
Arguments
myFile |
An 'ACER ConQuest' system file. |
NReg |
An integer representing the number of regressors in the model, a representation of 'ACER ConQuest' object gNReg. |
Value
A list
checkItemRespValid
Description
Check that the item responses in raw data are: (1) valid, (2) each valid response mapped to an item appears at least once, and (3) each valid reponse mapped to an item has sufficently many responses (defaults to a minimum of 10 observations for each response category)
Usage
checkItemRespValid(data, caseID, validMap, varLabel, validLabel)
Arguments
data |
Raw data, a data frame. |
caseID |
A string indicating the name of the case id variable in the data. |
validMap |
A data frame which contains a mapping of valid responses to item lables. This data frame shoudl be in long format, with each valis response * item conbination representing a row. |
varLabel |
A string indicating the name of the variable in validMap that identidies the valis items names/lables. |
validLabel |
A string indicating the name of the variable in validMap that contains the valid codes/responses for each item. This shoudl include missing values (e.g., "99") |
Value
A list of lists: one list per item in validMap$varLabel. Within each list, there can be up to three dfs: (1) the case ids and invalid responses for the item, (2) the valid codes not observed in the data set, and (3) the valid codes observed fewer than 10 times in the data. NOTE: a wanring is thrown if the validMap$varLabel is not found in the data.
checkNoExtraVars
Description
Check that the raw data does not include extraneous variables.
Usage
checkNoExtraVars(data, varNames, except = NULL)
Arguments
data |
Raw data, a data frame. |
varNames |
Vector of valid variable names. |
except |
A vector of variable names to be excluded form the check. |
Value
A list.
checkVars
Description
Check raw data: are all required variables preseent and ensure there are no extraneous variables.
Usage
checkVars(data, varNames, except = NULL)
Arguments
data |
Raw data, a data frame. |
varNames |
Vector of valid variable names. |
except |
A vector of variable names to be excluded form the check. |
Value
A list.
checkVarsExist
Description
Check that all required variables exist in raw data.
Usage
checkVarsExist(data, varNames)
Arguments
data |
Raw data, a data frame. |
varNames |
Vector of valid variable names. |
Value
A list.
cnvrtItemParam
Description
takes an item in one model's parameterisation and returns it in another parameterisation.
Usage
cnvrtItemParam(item, from = "muraki", to = "conquest", D = 1)
Arguments
item |
an item design matrix that is of size response categories (m) by four:
|
from |
a string, either "muraki" or "conquest" (default) (see 10.1177/0146621697211001). Describing the parameterisation of item |
to |
a string, either "muraki" or "conquest" (default) (see 10.1177/0146621697211001). Describing the output parameterisation of the returned item parameter matrix Note that "muraki" assumes the scaling constant D = 1.7 (to give the normal ogive metric) |
D |
a number, giving the scaling constant. Default is 1 (logistic metric). Other common values are D = 1.7 (to give the normal ogive metric) |
Value
an m x 4 matrix of item parameters. The same dimensions as the input, item
Examples
myTheta <- 0
myDelta <- 1.5
a <- 1.5
m <- 3
itemParamX <- seq(0, m-1, 1)
itemParamD <- rep(myDelta, m)
itemParamT <- c(0, -0.5, 0.5)
itemParamA <- rep(a, m)
itemParam <- cbind(itemParamX, itemParamD, itemParamT, itemParamA)
colnames(itemParam)<- c("x", "d", "t", "a")
myItem <- cnvrtItemParam(itemParam, from = "conquest", to = "muraki")
createConQuestProject
Description
creates a standard folder structure to work with 'ACER ConQuest' Projects.
Usage
createConQuestProject(prefix = getwd(), ...)
Arguments
prefix |
a valid file path where to create project folders. |
... |
optional params, including "setDebug" |
Value
Boolean TRUE.
Examples
## Not run:
createConQuestProject()
## End(Not run)
findConQuestExe
Description
Searches in common install paths to find ConQuest executable.
This is called by ConQuestCall when no executable is passed explicitly.
Usage
findConQuestExe()
Value
Char with path to ConQuest executable.
Examples
## Not run:
findConQuestExe()
## End(Not run)
fisherTrnsfrm
Description
Helper function to apply Fisher's transformation to a correlation matrix.
Usage
fisherTrnsfrm(myCorMat)
Arguments
myCorMat |
A correlation matrix. |
Value
A correlation matrix with Fisher's transform applied to values -1 > x > 1.
fmtCqItanal
Description
helper function to produce nicely formatted summary tables from a ConQuest Itanal.
Usage
fmtCqItanal(
cqItanal,
groups = "all",
itemNumber = "all",
ptBisFlag = 0,
textColHighlight = "red",
valueDecPlace = 2
)
Arguments
cqItanal |
An ACER ConQuest itanal list object returned by function |
groups |
a vector of group levels to include in the format. |
itemNumber |
a vector of generalised item numbers to format. |
ptBisFlag |
Something. |
textColHighlight |
Something. |
valueDecPlace |
Something. |
Value
A list
Examples
myEx1Sys <- ConQuestSys()
myEx1Sys_itanal <- getCqItanal(myEx1Sys)
myItanalSummary <- fmtCqItanal(myEx1Sys_itanal)
print(myItanalSummary[[1]])
fmtCqItanalSmry
Description
internal function to produce formatted itanal summary statistics seen at the end of a ConQuest itanal.
Note that this function is called by fmtCqItanal and would not usually be called by the user.
The returned table uses the library kable and will be formatted
based on the users settings.
Usage
fmtCqItanalSmry(cqItanalSmry, valueDecPlace)
Arguments
cqItanalSmry |
A single table in a cqItanal object (an element of type data.frame in a list of class "cqItanal". |
Value
A data frame.
fmtCqItanalTbl
Description
internal function to produce formatted itanal category statistics tables for a generalised item.
Note that this function is called by fmtCqItanal and would not usually be called by the user.
The returned table uses the library kable and will be formatted
based on the users settings.
Usage
fmtCqItanalTbl(
cqItanalTbl,
ptBisFlag,
textColHighlight,
valueDecPlace,
itemName
)
Arguments
cqItanalTbl |
A single table in a cqItanal object (an element of type data.frame in a list of class "cqItanal". |
Value
A data frame.
genItems
Description
Generates a list of item parameter matrices for use in
function like conquestr::genResponses and conquestr::informationWrightMap
Usage
genItems(n, scores = NULL, deltadots, taus, discrims = 1, centre = NULL)
Arguments
n |
How many items? |
scores |
When NULL it is assumed that all items have integer scoring, increasing for each category k, and beginning from 0. Otherwise a list where the elements are, in order:
|
deltadots |
A list that describes the sampling distribution from which item location paramters are drawn. The elements of the list are, in order:
|
taus |
A list that describes the sampling distribution from which taus are drawn. Taus are deviations away from the average item location parameter. The elements of the list are, in order:
|
discrims |
A list that describes the sampling distribution from which discrimination parameters are drawn.
|
centre |
A number indicating the value to centre the generated values in deltadots on. Typically 0 for identification purposes. If NULL then values are left at their generated values (e.g., deviating from the expected mean proportional to sampling error). |
Value
A list of item matrices.
See Also
simplef(), genResponses(), browseVignettes("conquestr")
Examples
myItem <- matrix(c(0, 0, 0, 0, 1, 1, 0, 1), ncol = 4, byrow = TRUE)
myItems <- list(myItem, myItem)
myItems[[2]][2, 2] <- -1 # make the second item delta equal to -1
myResponses <- genResponses(abilities = rnorm(100), itemParams = myItems)
genItems_deltaDots
Description
Internal function to parse deltaDots argument
to conquestr::genItems.
Usage
genItems_deltaDots(deltadots, n)
Arguments
deltadots |
A list that describes the sampling distribution from which item location parameters are drawn. |
n |
An integer describing the number of items being generated. |
Value
A vector of delta dots.
genItems_taus
Description
Internal function to parse taus argument
to conquestr::genItems.
Usage
genItems_taus(taus, n)
Arguments
taus |
A list that describes the sampling distribution from which item location parameters are drawn. |
n |
An integer describing the number of items being generated. |
Value
A list
genResponses
Description
Generates response vectors for n cases to i items given
known item parameters, person abilities, and (optionally) other inputs.
Usage
genResponses(
abilities,
groups = NULL,
itemParams,
BMatrix = 1,
mcarP = 0,
perturbR = NULL
)
Arguments
abilities |
A person by latent-dimension matrix of abilities. One column per dimension. |
groups |
A vector of factors of the same length as |
itemParams |
A list of item parameters of the structure used in |
BMatrix |
A simplified B-matrix mapping dimensions (columns) to items (rows). Or the integer "1" if items are dichotomous and ability is uni-dimensional. |
mcarP |
A double indicating the proportion of missing data under the MCAR assumption. |
perturbR |
A list of lists, where each element of the list refers to one item and contains a list of elements describing how responses to that item should be perturbed to model misfit. Each element of the list should contain, in order:
|
Value
A matrix, n cases by i items, of scored item responses.
See Also
simplef(), browseVignettes("conquestr")
Examples
myItem <- matrix(c(0, 0, 0, 0, 1, 1, 0, 1), ncol = 4, byrow = TRUE)
myItems <- list(myItem, myItem)
myItems[[2]][2, 2] <- -1 # make the second item delta equal to -1
myResponses <- genResponses(abilities = rnorm(100), itemParams = myItems)
geom_line_or_smooth
Description
helper functions for ggplot - conditionally creates call to
ggplot2::geom_smooth depending on the option linetype in the call to conquestr::plotCCC()
Usage
geom_line_or_smooth(thisData, thisLinetype)
Arguments
thisData |
the data frame being worked on in the call to |
thisLinetype |
a string, either "bins" or "regression" set in the call to |
Value
a list with a function call to ggplot2::geom_line.
Examples
myExample <- geom_line_or_smooth()
getCqChain
Description
creates a data frame representation of the estimation chain from an MCMC model. The burn is discarded and only the unskipped itterations in MCMC chain are retained.
Usage
getCqChain(myCqs)
Arguments
myCqs |
A system file. |
Value
A data frame.
Examples
## Not run:
getCqChain(ConQuestSys())
## End(Not run)
getCqData
Description
Get data objects from an R object of class ConQuestSys. This function returns person IDs, response data, case estimates, regression and weight data. Each data type is stored as a data frame, and each data frame is a named element of a list.
PID,
Responses,
Estimates,
Regression.
Usage
getCqData(mySys)
Arguments
mySys |
An R object of class ConQuestSys, returned by the function conquestr::ConQuestSys |
Value
A List of data frames.
See Also
conquestr::ConQuestSys()
Examples
mySys <- ConQuestSys()
myData <- getCqData(mySys)
getCqDataDf
Description
Takes a list object returned by conquestr::getCqData and coerces it to a wide data frame.
This can sometimes cause issues in complex data, for example where there are multiple response
vectors for each case (for example a many-facets model). This is because it is assumed that the data
can be reduced to a matrix of gNCases x m variables (where m is the number of id, item, estimate and
regression variables in the analysis). For more complex data, the user should use the outputs of
conquestr::getCqData to manually merge together a data frame.
Usage
getCqDataDf(cqData)
Arguments
cqData |
An R object of class list, returned by the function conquestr::getCqData |
Value
A data frame containing R data frames based on the list objects in the ConQuest system file that has been read in.
See Also
conquestr::ConQuestSys()
conquestr::getCqData
Examples
mySys <- ConQuestSys()
myData <- getCqData(mySys)
suppressWarnings(myDataDf <- getCqDataDf(myData)) # NAs introduced by coercion
getCqEsts
Description
Return ability estimates as a data frame.
Usage
getCqEsts(mySys)
Arguments
mySys |
An R object of class conQuestSysFile, returned by the function conquestr::ConQuestSys |
Value
A data frame containing ability estimates (missing if not estimated).
getCqFit
Description
creates a data frame representation of the fit of parameters in the item reponse model
Usage
getCqFit(myCqs)
Arguments
myCqs |
A system file. |
Value
A data frame.
Examples
## Not run:
getCqFit(ConQuestSys())
## End(Not run)
getCqHist
Description
creates a data frame representation of the iteration history for all parameters.
Usage
getCqHist(myCqs, labelParams = FALSE)
Arguments
myCqs |
An ACER ConQuest system file created using the conquest command, put. |
labelParams |
A boolean. When true, and if long (user) parameter labels are available, replace default history column names (e.g., "Xsi1") with user labels (e.g., "Item one"). Currently only available for Xsi and Tau. |
Value
A data frame.
See Also
getCqChain() which is a wrapper for this function
to use with models estimated by Markov chain Monte Carlo (MCMC) methods.
Examples
myHist <- getCqHist(ConQuestSys(), labelParams = TRUE)
str(myHist)
getCqItanal
Description
helper function to return list of lists, each list relates to one
generalised item from an ACER ConQuest itanal output.
Each list contains: (1) item-total and item-rest correlations ....
Usage
getCqItanal(sysFile, matrixPrefix = NULL, isDebug = FALSE)
Arguments
sysFile |
An ACER ConQuest system file. |
matrixPrefix |
The name of the itanal analysis defined in ACER ConQuest.
For example, in ACER ConQuest syntax |
isDebug |
A boolean to toggle on or off debug output |
Value
A list.
Examples
myItanal <- getCqItanal()
print(myItanal[[1]])
getCqItanalFacility
Description
returns an item facility for each item in itanal object created by ACER ConQuest. For a dichotomously scored Rasch-like item, facility is the percent correct. For a polytomously scored item, or with estimated scores, facility is given by: the sum of the number of cases in each response category, multiplied by the score for that category divided by the sum of all cases responding to the items times the maximum score for the item.
Usage
getCqItanalFacility(itan)
Arguments
itan |
A list of class "cqItanal" created by |
Value
A list.
Examples
mySys <- ConQuestSys()
myItan <- getCqItanal(mySys)
getCqItanalFacility(myItan)
getCqItanalSummary
Description
returns an itanal as a data frame in summary format: one row per generalised item with:
item label
valid N
facility (see
conquestr::getCqItanalFacility)item-rest correlation
item-total correlation
fit (infit/weighted MNSQ) if available
item locations (deltas)
Usage
getCqItanalSummary(itan)
Arguments
itan |
A list of class "cqItanal" created by |
Value
A data frame.
Examples
mySys <- ConQuestSys()
myItan <- getCqItanal(mySys)
getCqItanalSummary(myItan)
getCqKeys
Description
internal function to return keys associated with item categories in itanal tables.
Usage
getCqKeys(sysFile)
Arguments
sysFile |
An ACER ConQuest system file. |
Value
A data frame.
getCqLongLabs
Description
returns a vector of long gin labels returns vector of length 0 if there are no labels used (see command labels in conquest)
Usage
getCqLongLabs(sysFile)
Arguments
sysFile |
An ACER ConQuest system file read into R using conquestr::ConQuestSys. |
Value
A vector.
Examples
## Not run:
getCqLongLabs(ConQuestSys())
## End(Not run)
getCqParams
Description
creates a data frame representation of the parameters of the model, including both estimated, constrained, and anchored parameters.
Usage
getCqParams(sysFile)
Arguments
sysFile |
An ACER ConQuest system file read into R using conquestr::ConQuestSys. |
Value
A data frame.
Examples
## Not run:
getCqParams(ConQuestSys())
## End(Not run)
getCqPid
Description
Return PID as a data frame.
Usage
getCqPid(mySys)
Arguments
mySys |
An R object of class conQuestSysFile, returned by the function conquestr::ConQuestSys |
Value
A data frame containing sequence number and PID (if no PID is declared, this is the sequence number).
getCqResp
Description
Return item responses as a data frame.
Usage
getCqResp(mySys)
Arguments
mySys |
An R object of class conQuestSysFile, returned by the function conquestr::ConQuestSys |
Value
A data frame containing raw item responses (pre key) and scored item response (post key).
getCqRespModel
Description
produces a table of model parameter estimates, errors, fits, and scaled 2PL estimates if available.
Usage
getCqRespModel(sysFile)
Arguments
sysFile |
An ACER ConQuest system file read into R using conquestr::ConQuestSys |
Value
A List of data frames. Each data frame is a term in the response model
Examples
## Not run:
myShowRespMod <- getCqRespModel(conquestr::ConQuestSys())
## End(Not run)
getCqScores
Description
internal function to return scores associated with item categories in itanal tables.
Usage
getCqScores(sysFile)
Arguments
sysFile |
An ACER ConQuest system file. |
Value
A data frame.
getCqTerms
Description
creates a data frame representation of the terms of the model statement, including interactions.
Usage
getCqTerms(myCqs)
Arguments
myCqs |
A system file. |
Value
A data frame.
Examples
## Not run:
getCqTerms(ConQuestSys())
## End(Not run)
getCqVars
Description
creates a data frame representation of the variables in the model statement. Note that steps are not variables.
Usage
getCqVars(myCqs)
Arguments
myCqs |
A system file. |
Value
A data frame.
Examples
## Not run:
getCqVars(ConQuestSys())
## End(Not run)
getCqYData
Description
Return weight and regression data as a data frame.
Usage
getCqYData(mySys)
Arguments
mySys |
An R object of class conQuestSysFile, returned by the function conquestr::ConQuestSys |
Value
A data frame containing weight and regression data.
getItemMatrix
Description
generates an item matrix. Useful for
Usage
getItemMatrix(responses, itemParams, ...)
Arguments
responses |
a data frame made up of rows of vectors of item responses, one for each case. |
itemParams |
a list of item designs (each used in a call to |
... |
optional arguments, e.g., perfAdj. |
Value
a data frame.
ginsOnDims
Description
returns a list of length gNDims. Each element of the list contains a vector of the gins on this dim.
Usage
ginsOnDims(sysFile)
Arguments
sysFile |
An ACER ConQuest system file read into R using conquestr::ConQuestSys |
Value
a list
Examples
## Not run:
myResult <- ginsOnDims(conquestr::ConQuestSys())
## End(Not run)
guide_remove_groups
Description
helper functions for ggplot - conditionally creates call to
ggplot2::guides to remove legends that involve groups when there is
no groups in the call to conquestr::plotCCC()
Usage
guide_remove_groups(groups = TRUE)
Arguments
groups |
A bool indicating if there is groups in the call to |
Value
a list with a function call to ggplot2::guides.
Examples
myExample <- guide_remove_groups(TRUE)
guide_remove_linetype
Description
helper functions for ggplot - conditionally creates call to
ggplot2::guides to remove legends that involve groups when there is
no groups in the call to conquestr::plotCCC()
Usage
guide_remove_linetype(groups = TRUE)
Arguments
groups |
A bool indicating if there is groups in the call to |
Value
a list with a call to ggplot2::guides.
Examples
myExample <- guide_remove_linetype(TRUE)
infoWI
Description
Calculates an index representing the product of a test information function and an ability distribution.
Usage
infoWI(myItems, myAbilities, type = "empirical")
Arguments
myItems |
A vector of item deltas. |
myAbilities |
A vector of person abilities. |
type |
A character String. Should the test information be calculated empirically ("empirical" - default) or analytically using moments of distribution ("approx"). |
Value
A double.
Examples
infoWIOut <- infoWI(runif (10, -2, 3), rnorm(1000, 0, 1))
informationWrightMap
Description
Plots test information function, relative to ability density, and item locations.
Usage
informationWrightMap(
myItems,
myAbilities,
type = "empirical",
minTheta = NA,
maxTheta = NA,
stepTheta = NA,
scaleInfo = 1,
plotItemPoints = "deltadots"
)
Arguments
myItems |
A list of matricies describing item parameters. |
myAbilities |
A vector of person abilities on one dimension. |
type |
A character String. Should the test information be calculated empirically ("empirical" - default) or analytically using moments of distribution ("approx"). |
minTheta |
The smallest value of ability PDF to plot. |
maxTheta |
The largest value of ability PDF to plot. |
stepTheta |
The increment to iterate over the ability PDF. Defaults to 0.01. |
scaleInfo |
A scaling factor to apply to the plot of tesr information. Because ability distribution is a PDF with area one, and a test information function has area L, this can make the plot more interpretable. Defaults to 1. |
plotItemPoints |
A character string indicating what item points should be plotted along the x-axis. similar to the histogram of item locations plotted on a Wrightmap. Can be "none", "deltadots", "thresholds". |
Value
A ggplot2 object.
Examples
myDeltaDots <- data.frame(
id = c(1:10),
itemid = paste0("item", 1:10),
delta = rnorm(10)
)
MyTaus <- data.frame(
id = c(2L, 10L),
itemId = NA,
step = c(1L, 1L),
tau = rnorm(2)
)
myItemList <- makeItemList(deltaDot = myDeltaDots, tau = MyTaus)
myInfoPlot <- informationWrightMap(myItemList, rnorm(1000, 0, 1), minTheta=-5, maxTheta=5)
isCqConverged
Description
returns true is the ConQuest model has converged normally (system file).
Usage
isCqConverged(myCqs)
Arguments
myCqs |
A system file. |
Value
A boolean.
Examples
## Not run:
isCqConverged(ConQuestSys())
## End(Not run)
itemInfoAtTheta
Description
Calculates item information at a value of theta given a set of item parameters for one item.
Usage
itemInfoAtTheta(myItem, theta)
Arguments
myItem |
A matrix of item parameters of the structure used in |
theta |
A number. |
Examples
anItem <- matrix(c(0,0,0,1,1,1,0,1), nrow = 2, byrow = TRUE)
itemInfoAtTheta(anItem, 0)
itemInfoOverTheta
Description
Calculates item information over a rage of theta given a set of item parameters. Returns a data frame with item information at a discrete set of values of theta. This is useful for plotting item information functions.
Note this function is redundant - use testInfoOverTheta and pass a single item as a list.
Usage
itemInfoOverTheta(myItem, minTheta = -6, maxTheta = 6, stepTheta = 0.1)
Arguments
myItem |
A matrix of item parameters of the structure used in |
minTheta |
The smallest value of ability PDF to calculate info and to plot. Defaults to -6. |
maxTheta |
The largest value of ability PDF to calculate info and to plot. Defaults to 6. |
stepTheta |
The increment to iterate over the ability PDF. Defaults to 0.01. |
Examples
anItem <- matrix(c(0,0,0,1,1,1,0,1), nrow = 2, byrow = TRUE)
itemInfoOverTheta(anItem)
itemListToDeltaDots
Description
Taskes a list of item parameter matricies and returns a data frame containing delta dots. This is mostly an internal function used, for example to plot items on Wright Maps.
Usage
itemListToDeltaDots(myItems)
Value
A data frame including 4 columns:
id, an integer index reflecting which item this is, in the same order as myItems
itemid, a string with the names from the items in myItems (NA if item list is not named)
location, the value of the deta dot
Examples
myItem <- matrix(
c(
0, -0.58 , 0 , 1, # delta+tau thurst thresh (gamma)
1, -0.58 , 0.776 , 1, # 0.196 -1.14
2, -0.58 , -0.697 , 1, # -1.277 -0.93
3, -0.58 , -0.629 , 1, # -1.209 -0.64
4, -0.58 , 0.55 , 1 # -0.03 0.25
), ncol =4, byrow=TRUE
)
thrstThrsh(myItem)
itemListToThresholds
Description
Taskes a list of item parameter matricies and returns a data frame containing Thurstonian Thresholds (gammas) for all items. Thurstonian thresholds are the location on the trait/scale at which the cumulative probability of being in category k, or any higher category equals some probability (usually 0.5, the default). Thurstonian thresholds are considered a way of describing the difficulty of polytomously scored items and are usually the value used in visualisations like Wright maps. Thurstonian thresholds can only be calculated for items where response categories are scored such that each category can be placed in an order increasing scores (e.g., no ties as per the Ordered Partition model)
Usage
itemListToThresholds(
myItems,
threshP = 0.5,
minTheta = -20,
maxTheta = 20,
convC = 1e-05
)
Arguments
myItems |
A list of item parameter matricies of the structure used in |
threshP |
The probability at which the thresholds are calculated (defaults to the usual value of 0.5) |
minTheta |
The lower-bound starting value of the split-half search used to find the threshold for the category. |
maxTheta |
The upper-bound starting value of the split-half search used to find the threshold for the category. |
convC |
The convergence criteria used to determine when the threshold has been found. The difference between
|
Value
A data frame including 4 columns:
id, an integer index reflecting which item this is, in the same order as myItems
itemid, a string with the names from the items in myItems (NA if item list is not named)
step, which step does this threshold belong?
location, the value of the threshold
Examples
myItem <- matrix(
c(
0, -0.58 , 0 , 1, # delta+tau thurst thresh (gamma)
1, -0.58 , 0.776 , 1, # 0.196 -1.14
2, -0.58 , -0.697 , 1, # -1.277 -0.93
3, -0.58 , -0.629 , 1, # -1.209 -0.64
4, -0.58 , 0.55 , 1 # -0.03 0.25
), ncol =4, byrow=TRUE
)
itemListToThresholds(list(myItem))
itemResp
Description
Returns a probabilistic item response, given one ability and one set of item parameters.
Usage
itemResp(myAblty, myItem)
Arguments
myAblty |
A numeric ability. |
myItem |
A single item (a matrix k categories by four (category score, delta dot, tau, discrimination). |
Value
A numeric score, usually an integer in the range 0, 1, 2, ..., k-1. This is taken from the first column of the matrix of item parameters so may also contain a numeric score.
Examples
myItem <- matrix(c(0, 0, 0, 0, 1, 1, 0, 1), ncol = 4, byrow = TRUE)
itemResp(0, myItem)
makeItemDfs
Description
takes in a list of item matrices and returns a list of data frames
each representing the parameters given in the matrices. The return object is
suitable to pass into conquestr::makeItemList to construct a lit of matrices
where each matrix represent one item's set of item parameters. The structure of the
matrix is the same as used in conquestr::simplef
(a matrix of k categories by four (category score, delta dot, tau, discrimination)).
A common use for this function is turn a list of item matrices into a flat data
structure.
Usage
makeItemDfs(itemList)
Arguments
itemList |
a list of item matrices. The structure of each
matrix is the same as used in |
Value
a list.
Examples
nItems <- 10
myItemsDeltaDot <- data.frame(
id= seq(nItems),
itemid= NA,
delta = runif (nItems, -4, 1) # nItems items in range -4,1
)
myItemsList <- conquestr::makeItemList(deltaDot = myItemsDeltaDot)
makeItemList
Description
creates a list of item matrices.
Each matrix represent one item's set of item parameters. The structure of the
matrix is the same as used in conquestr::simplef
(a matrix of k categories by four (category score, delta dot, tau, discrimination)).
Usage
makeItemList(scores = NULL, deltaDot, tau = NULL, discrim = 1)
Arguments
scores |
a data frame or matrix containing category scores for each item.
If NULL, it is assumed increasing integer scoring starting at 0 is used for all items (that is, the
first category is scored 0, the second category is scored 1, the If a data frame, column labels should be "id", "itemid", "step", "score".
If a matrix, the column order should be: "id", a unique item ID for each item matched with values in If a data frame, or a matrix:
|
deltaDot |
a data frame or matrix of delta dots (average item location/difficulty for each item). If a data frame, column labels should be: "id", "itemid", "delta". "itemid" should be populated with an item label or be missing for all values. If a matrix, column order should be: "id", a unique item ID for each row; "itemid", item labels for each item (or NA); "delta", a delta dot. If a data frame, or a matrix:
|
tau |
NULL if all items are dichotomies.
A data frame or matrix of taus for polytomous items. Only polytomous items should be in this file.
If an item ID in Where a polytomous item has k categories, there should be k-2 rows for that item in If a data frame, column labels should be "id", "itemid", "step", "tau".
If a matrix, the column order should be: "id", a unique item ID for each item matched with values in If a data frame, or a matrix:
|
discrim |
a double, a data frame, or a matrix of item (or category) discrimination parameters. When a double is provided, the value is applied to all discrimination parameters. The default is 1. Setting the value to 1.7 is one approach to re-scale to the normal ogive metric. Otherwise a data.frame or matrix defining the discrimination parameter for each response category. If a data frame, column labels should be "id", "itemid", "step", "discrim". If step is NA and there is only one entry for an item "itemid", the discrimination is assumed to be constant for all response categories with the item. This is the case for named models like the GPCM and 2PL models, and can be a short hand way of defining the discrimination without specifying all categories. When discrimination varies across scoring categories, the Bock-nominal model is implied. In the case of discrimination varying across scoring categories, all categories must be defined. If a data frame, or a matrix:
|
Value
a list.
Examples
nItems <- 10
myItemsDeltaDot <- data.frame(
id= seq(nItems),
itemid= NA,
delta = runif (nItems, -4, 1) # nItems items in range -4,1
)
myItemsList <- conquestr::makeItemList(deltaDot = myItemsDeltaDot)
mleCalc
Description
returns the MLE for each case and asymptotic variance given a fixed set of item parameters. This is done by finding the root of the distance between the observed and expected score at theta. That is, the location where O-E = 0.
Usage
mleCalc(responses, itemParams, ...)
Arguments
responses |
a data frame made up of rows of vectors of item responses, one for each case. |
itemParams |
a list of item designs (each used in a call to |
... |
optional arguments, e.g., perfAdj. |
Value
a data frame.
myAbilitiesHelper
Description
helper function to return attributes of vector of abilities for use in information function and WI.
Usage
myAbilitiesHelper(myWhat = "ok", myAbilities = NA)
Arguments
myWhat |
A character string indicating what to check. |
myAbilities |
A numeric vector of person abilities. |
Value
A Boolean or a double.
myItemHelper
Description
helper function to return attributes of list of items for use in information function helpers and WI.
Usage
myItemHelper(myWhat = "ok", myItems)
Arguments
myWhat |
A character string indicating what to check. |
myItems |
A list of item matricies. |
Value
A Boolean or a double.
orderItanalCols
Description
internal function to order and rename itanal tables. Called by conquestr::fmtCqItanalTbl Safely orders and renames tables when ndim > 1.
Usage
orderItanalCols(itanalTbl)
Arguments
itanalTbl |
An itanal table being worked on by fmtCqItanalTbl. |
Value
A data frame.
pX
Description
returns response probabilities for given response x to an item.
Usage
pX(x, probs)
Arguments
x |
a scalar integer - a response to an item (usually in the range 0, k-1, where k is the number of response categories). |
probs |
a matrix returned from simplef. |
Value
a 1 x 1 matrix giving the response probability of x.
Examples
myTheta <- 0
myDelta <- 1.5
k <- 3
a <- 1.25
itemParamX <- seq(0, k-1, 1)
itemParamD <- rep(myDelta, k)
itemParamT <- c(0, -0.5, 0.5)
itemParamA <- rep(a, k)
itemParam <- cbind(itemParamX, itemParamD, itemParamT, itemParamA)
colnames(itemParam)<- c("x", "d", "t", "a")
myProbs <- simplef(myTheta, itemParam)
myProb <- pX(0, myProbs)
perturbResp
Description
Perturbs a response given specified (item) misfit to implied model.
Usage
perturbResp(ability, item, group, perturbation)
Arguments
ability |
a double - the location of the person on the measure. |
item |
a matrix - the item parameters in the format required by
|
group |
a string - the group this case belongs to. If NULL, the case is always in this group. |
perturbation |
A matrix - the description of the way this item should be
perturbed. In the format required by |
Value
A double - the observed response.
See Also
simplef(), genResponses(),
browseVignettes("conquestr")
Examples
myN <- 250
myMean <- 0
mySd <- 2
myGroups <- c("gfit", "bfit")
myAbilities <- rnorm(myN, myMean, mySd)
# students with large weights and unperturbed responses (good fit)
# and students with small weights and perturbed responses (bad fit)
myData <- data.frame(
ability = myAbilities,
group = factor(sample(x = myGroups, size = myN, replace = TRUE))
)
myData$weight <- ifelse(myData$group == myGroups[1], 1, 0.001)
myItems <- list()
myItems[[1]] <- matrix(c(
0, 0, 0 , 1,
1, 1, -0.2, 1,
2, 1, 0.2 , 1
), ncol = 4, byrow = TRUE)
myPerturbations<- list()
myPerturbations[[1]] <- list()
myPerturbations[[1]] <- append(myPerturbations[[1]], 1L)
myPerturbations[[1]] <- append(myPerturbations[[1]], "discrimination")
myPerturbations[[1]] <- append(myPerturbations[[1]], 0.50)
myPerturbations[[1]] <- append(myPerturbations[[1]], 0)
myPerturbations[[1]] <- append(myPerturbations[[1]], "bfit")
names(myPerturbations[[1]]) <- c("item", "type", "factor", "pivot", "group")
myResponses <- genResponses(
abilities = myData$ability, itemParams = myItems, perturbR = myPerturbations,
groups = myData$group
)
plotCCC
Description
Creates a plot of an item characteristic curve (by response category).
For a dichotomous item, this will yield a single curve, for polytomous items this
will produce a curve for each response category.
Note this is not for use with rout files. See the generic function plotRout for plotting rout files.
Usage
plotCCC(
item,
abilities,
responses,
weights = NULL,
groups = NULL,
range = c(-6, 6),
by = 0.1,
linetype = "bins",
bins = 10,
plotZero
)
Arguments
item |
A matrix of item parameters for a single item. Matrix should be of
the form used in |
abilities |
A vector of doubles estimated person abilities. |
responses |
A vector of integers giving the observed person responses to this item. |
weights |
A vector of doubles of sampling weights. |
groups |
A factor vector indicating groups. |
range |
Lower and upper bounds to plot over (defaults to |
by |
A double. The increment to the sequence along |
linetype |
A string. Should the empirical lines be based on "bins", or "regression". Defaults to "bins" |
bins |
If linetype is "bins", how many bins should be used to chunk the empirical lines? defaults to 10. Ignored otherwise. |
plotZero |
Should the zero category be plotted?
Defaults to |
Value
A ggplot2 object.
Examples
myRout <- ConQuestRout()
myPlot <- plotRout(myRout)
## Not run:
# if you run the above example you will have an ICC plot in the object `myPlot`.
plot(myPlot)
## End(Not run)
plotCqHist
Description
generates a plot from a history object.
Use getCqHist to create a history object from an 'ACER ConQuest' system file.
Usage
plotCqHist(
myHist,
centre = TRUE,
params = c("all"),
legend = FALSE,
plotProblems = NULL
)
Arguments
myHist |
an R object created by the |
centre |
a Boolean representing whether the iteration history should be mean centred (within parameter). This is helpful for plots that include all parameters to ensure the Y axis is sensible. Consider, for example, the readability of a plot with raw values of the Likelihood and item parameters on it. |
params |
A string of which params to plot. Must be one or more of "all", "Likelihood", "Beta", Variance", "Xsi", "Tau". Note the match when using "Beta", Variance", "Xsi", "Tau" is by regular expression, so "Xsi1" will plot item location parameter 1, 10-19, 100-199 and so on. |
legend |
Should a legend be plotted? |
plotProblems |
an optional list defining which potential problem parameters to plot.
|
Value
A ggplot2 object.
Examples
## Not run:
myHistPlot <- plotCqHist(getCqHist(ConQuestSys()))
## End(Not run)
plotDif
Description
Creates a plot (ggplot2 object) of item parameter estimates common to two system files (e.g., a DIF analysis).
Usage
plotDif(mySysToItemDifDf, myScale = "centred", mySuffixes)
Arguments
mySysToItemDifDf |
An R object of class data frame returned from conquestr::sysToItemDifDf |
myScale |
A string specifying if the item parameter estimates displayed should be "centred" (default), "scaled" (z scores), or "none" (raw). |
mySuffixes |
a vector of strings specifying the names for the two groups being analysed,
e.g., if the two system files are an analysis of boys and girls, the vector may be |
Value
A ggplot2 object.
See Also
conquestr::sysToItemDifDf()
Examples
mySys1 <- ConQuestSys()
mySys2 <- ConQuestSys()
mySysList <- list(mySys1, mySys2)
myDifDf <- sysToItemDifDf(mySysList, mySuffixes = c("_male", "_female"), myDims = "all")
myDifPlot <- plotDif (myDifDf,myScale = "centred", mySuffixes = c("_male", "_female"))
## Not run:
# if you run the above example you will have the plot in the object `myDifPlot`.
plot(myDifPlot)
## End(Not run)
plotItemMap
Description
Creates a plot (ggplot2 object) of item parameter
estimates and abilities on latent trait. Note this is not for
use with rout files. See the method method plotRout.itemMap
to the generic function plotRout
Usage
plotItemMap(mySys, myDims = "D1", ginLabs = "short", abilityType = "PV", ...)
Arguments
mySys |
An 'ACER ConQuest' system file object created using the conquestr::ConQuestSys function. |
myDims |
A string specifying which specific dimensions should be included. The default is "D1", Specific dimensions are specified by the label "D1" for dimensions 1 etc. |
ginLabs |
A string specifying whether short or long gin labels should be used. Default to "short". |
abilityType |
What kind of person ability estimate should be used? Defaults to plausible values. Alternatively WLE, MLE, EAP. |
... |
Optional arguments, mostly for debugging, e.g., |
Value
A ggplot2 object.
Examples
mySys1 <- ConQuestSys()
myItemMap <- plotItemMap(mySys1)
## Not run:
# if you run the above example you will have the plot in the object `myItemMap`.
plot(myItemMap)
## End(Not run)
plotModelCCC
Description
Creates a plot of a model implied category characteristic curve.
Note this is not for use with rout files. See the generic function plotRout for plotting rout files.
Usage
plotModelCCC(item, range = c(-6, 6), by = 0.1, plotZero)
Arguments
item |
Item parameters for a single item. |
range |
Lower and upper bounds to plot over (defaults to c(-6, 6). |
by |
Increment to the sequence along 'range“. |
plotZero |
Should the zero category be plotted?
Defaults to |
Value
A ggplot2 object.
Examples
myItem <- matrix(
c(
0, 0, 0, 1,
1, 1, 0, 1
),
ncol = 4, byrow=TRUE
)
myPlot <- plotModelCCC(myItem)
plotExpected
Description
Creates a plot of an item- or test- expected score curve.
If ability estimates are provided, both empirical and model curves are produced.
Can optionally handle weights and groups as required.
Note this is not for use with rout files. See the generic function plotRout for plotting rout files.
Usage
plotModelExp(
items,
range = c(-6, 6),
by = 0.1,
bins = NULL,
abilities = NULL,
weights = NULL,
group = NULL,
scale = FALSE
)
Arguments
items |
a list of one or more matrices of item parameters. Used in producing model-implied curves. |
range |
Lower and upper bounds to plot over (defaults to c(-6, 6). Used in producing model-implied curves. For empirical curves a range is chosen given the min and max values in abilities. |
by |
Increment to calculate expectation along |
bins |
A double. Optional. How many equally sized bins should abilities be broken up into? Used in producing empirical curves. If not provided and abilities are provided, a suitable value is chosen given the length of abilities. |
abilities |
A vector of doubles. Optional. |
weights |
A vector of doubles. Optional. |
group |
A vector of type factor. Optional. |
scale |
A Boolean. Whether plot should be scaled such that the Y-axis ranges from 0 to 1. |
Value
A ggplot2 object.
Examples
myItem <- matrix(
c(
0, 0, 0, 1,
1, 1, 0, 1
),
ncol = 4, byrow=TRUE
)
myPlot <- plotModelExp(list(myItem))
plotRout
Description
generates a plot from an 'ACER ConQuest' Rout file. use ConQuestRout to read in an Rout
file created by a plot command in 'ACER ConQuest'.
Usage
plotRout(myRout, ...)
## S3 method for class 'TestInfo'
plotRout(myRout, ...)
## S3 method for class 'InformationWithLatentDist'
plotRout(myRout, ...)
## S3 method for class 'ICC'
plotRout(myRout, ...)
## S3 method for class 'MCC'
plotRout(myRout, ...)
## S3 method for class 'TCC'
plotRout(myRout, ...)
## Default S3 method:
plotRout(myRout, ...)
Arguments
myRout |
an R object created by the |
... |
additional arguments passed into plotting functions |
Value
A ggplot2 object.
Examples
myRout <- ConQuestRout()
myPlot <- plotRout(myRout)
## to see why we import this, see https://ggplot2.tidyverse.org/articles/ggplot2-in-packages.html
postProcessGncases
Description
internal function to processing gNCases
Usage
postProcessGncases(this_gNCases, debug)
Arguments
this_gNCases |
An object of type gNCases from a list of class conQuestSysFile |
debug |
is this a debug run? |
Value
A list containing a documented gNCases object
See Also
conquestr::postProcessSys()
postProcessSys
Description
Post processing of ConQuest system file created by ConQuestSys. Adds names and attributes (e.g., descriptions) to objects in list.
Usage
postProcessSys(sysFile)
Arguments
sysFile |
A list of class conQuestSysFile |
Value
A list containing the data objects created by 'ACER ConQuest'. Object is of class conQuestSysFile.
See Also
conquestr::ConQuestSys()
pvMeanVar
Description
Applies the law of total variance (EVEs law) to calculate the mean and variance of a set of PVs for one dimension.
Usage
pvMeanVar(myData)
Arguments
myData |
A matrix of PVs for one dimension: m PVs by n cases. |
Value
A list containing the mean and variance of the PVs.
q3ExpCorrect
Description
Helper function to apply correction to correlation matrix. When working with standardised residuals, the expectation of the correlations is -1/(L-1) rather than 0 See DOI: 10.1177/0013164410379322
Usage
q3ExpCorrect(myCorMat)
Arguments
myCorMat |
A correlation matrix. |
Value
A correlation matrix with the Q3 statistic correction applied.
rawScore
Description
returns the adjusted (for zero and perfects) and unadjusted raw scores as well as the maximum score.
Usage
rawScore(x, itemParams, perfAdjust = 0.3)
Arguments
x |
a vector of scored item responses. Order of item responses is the same as the order of |
itemParams |
A list of item params of the structure used in |
perfAdjust |
the correction factor for zeros and perfects to be add/subtracted from the raw score. |
Value
a list containing three elements: (1) raw score (unadjusted), (2) raw score (adjusted), (3) maximum score.
readCharSafe
Description
reads n bytes as raw from a binary connection.
Removes any embedded nuls, replacing them with replace.
Usage
readCharSafe(con, n, replace = " ")
Arguments
con |
A file connection - usually a binary file. |
n |
The number of bytes to read. |
replace |
a character to replace embedded nulls with. |
Value
character vector.
recodeResps
Description
Recode raw item responses for analyses.
Usage
recodeResps(data, recodeMap, varLabel, rawLabel, recodeLabel)
Arguments
data |
Raw data, a data frame. |
recodeMap |
A data frame which contains the raw responses and corresponding recoded responses for each of the items in long form. |
varLabel |
A variable name in recodeMap that identifes the item label. |
rawLabel |
A variable name in recodeMap that identifies the raw item responses to be recoded. |
recodeLabel |
A variable name in recodeMap that idenitfies the new values to recode to. |
Value
a data frame with raw data recoded according to recodeMap.
iterate through a data frame and use replaceInVector
Description
iterate through a data frame and use replaceInVector
Usage
replaceInDataFrame(d, r, x)
Arguments
d |
A DataFrame. |
r |
A double - the value to be replaced if it is < -1e300. |
x |
A double - the value to replace r with. |
replace a very large neagtive number with something - usually NA_REAL
Description
replace a very large neagtive number with something - usually NA_REAL
Usage
replaceInVector(v, r, x)
Arguments
v |
A NumericVector. |
r |
A double - the value to be replaced if it is < -1e300. |
x |
A double - the value to repalce r with. |
routPointsToDf
Description
routPointsToDf
Usage
routPointsToDf(myRout)
Arguments
myRout |
An 'ACER ConQuest' Rout file created by a call to 'plot' in 'ACER ConQuest'. |
Value
A data frame containing the series that make up the plot
routType
Description
routType
Usage
routType(myRout)
Arguments
myRout |
An 'ACER ConQuest' Rout file created by a call to 'plot' in 'ACER ConQuest'. |
Value
A string naming the type of plot
searchConQuestSys
Description
Search for object names within a ConQuest System file object.
Usage
searchConQuestSys(searchString, mySys, value = TRUE, ignore.case = TRUE)
Arguments
searchString |
A string to search within the names of mySys. |
mySys |
An 'ACER ConQuest' system file object created using the conquestr::ConQuestSys function. |
value |
Should searchConQuestSys return the name of the object or its index. |
ignore.case |
Should searchConQuestSys ignore the case of the search term. |
Value
a string including object names mathching the search term
simplef
Description
returns expected score at a given value of theta.
Usage
simplef(theta, item, model, D)
Arguments
theta |
a scalar value of theta. |
item |
an item design matrix that is of size response categories (k) by three. The three columns are:
|
model |
a string, either "muraki" or "conquest" (default) (see 10.1177/0146621697211001). This tells downstream functions what parameterisation has been used for the model and helps with plotting and other outputs. |
D |
a number, giving the scaling constant. Default is 1 (logistic metric). Other common values are D = 1.7 (to give the normal ogive metric) |
Value
a double - the expected score at theta.
Examples
myTheta <- 0
myDelta <- 1.5
k <- 3
a <- 1
itemParamX <- seq(0, k-1, 1)
itemParamD <- rep(myDelta, k)
itemParamT <- c(0, -0.5, 0.5)
itemParamA <- rep(a, k)
itemParam <- cbind(itemParamX, itemParamD, itemParamT, itemParamA)
colnames(itemParam)<- c("x", "d", "t", "a")
myExpect <- simplef(myTheta, itemParam)
simplep
Description
returns response probabilities for each response category of an item at a given value of theta.
Usage
simplep(theta, item, model = "conquest", D = 1)
Arguments
theta |
a scalar value of theta. |
item |
an item design matrix that is of size response categories (m) by four:
|
model |
a string, either "muraki" or "conquest" (default) (see 10.1177/0146621697211001). This tells downstream functions what parameterisation has been used for the model and helps with plotting and other outputs. |
D |
a number, giving the scaling constant. Default is 1 (logistic metric). Other common values are D = 1.7 (to give the normal ogive metric) |
Value
a k x 1 matrix of response probabilities evaluated at theta.
Examples
myTheta <- 0
myDelta <- 1.5
a <- 1.5
k <- 3
itemParamX <- seq(0, k-1, 1)
itemParamD <- c(0, rep(myDelta, k-1))
itemParamT <- c(0, -0.5, 0.5)
itemParamA <- rep(a, k)
itemParam <- cbind(itemParamX, itemParamD, itemParamT, itemParamA)
colnames(itemParam)<- c("x", "d", "t", "a")
myProbs <- simplep(myTheta, itemParam)
steigerStat
Description
Function to cacluate the Steiger statistic. The Steiger statistic is a test of independance of the standardised residuals ((O-E)/sqrt(Var(E))), where Var(E) = p(x)/(1-p(x)).
Usage
steigerStat(myDat, q3Adj = TRUE, fisher = TRUE, dfAdj = FALSE, tpm)
Arguments
myDat |
A data frame or matrix containing standardised residuals. |
q3Adj |
A bool indicating whether the Q3 correction should be applied. |
fisher |
A bool indicating whether the Fisher Transform should be applied. |
dfAdj |
A bool indicating whether the df should be adjusted for sample size, L, and targeting.
If dfAdj is TRUE, then you must pass in the optional argument |
tpm |
A number indicating the test-person match, where 0 indicates that mean item difficulty is equal to mean person ability, and -1 indcates that mean item difficulty is 1 logit below mean person ability. |
Value
A list of class "steigerStat" with the Steiger Statistic, correlation matrix, and chi square test.
summariseCqChain
Description
takes a data frame created by getCqChain and returns a list reporting the mean and variaince for each parameter
Usage
summariseCqChain(myChain)
Arguments
myChain |
A data frame returned from getCqChain. |
Value
A list.
Examples
## Not run:
summariseCqChain(getCqChain(ConQuestSys()))
## End(Not run)
sysFileOk
Description
checks
Usage
sysFileOk(sysFile, defaultSys)
Arguments
sysFile |
An ACER ConQuest system file read into R using conquestr::ConQuestSys |
defaultSys |
A Boolean indicating if sysFile is the defualt system file created by an empty call to conquestr::ConQuestSys |
Examples
## Not run:
sysFileOkResult <- sysFileOk(conquestr::ConQuestSys())
## End(Not run)
sysToBMatrixDf
Description
Read an R object of class ConQuestSys and create a labelled representation of the B matrix (scoring matrix). This maps item response categories to items and dimensions. Returns long data frame, where items are duplicated if they are in many dimensions.
Usage
sysToBMatrixDf(mySys, applyLabels = TRUE)
Arguments
mySys |
An R object of class ConQuestSys, returned by the function conquestr::ConQuestSys |
applyLabels |
A bool indicating whether labels (e.g., dimension labels) should be appended. |
Value
A data frame containing R the labelled B matrix.
Examples
myBMatrix <- sysToBMatrixDf(ConQuestSys())
## Not run:
# if you run the above example you will have the B Matrix from the example system file.
str(myBMatrix)
## End(Not run)
sysToDimLabels
Description
Gets dimensions labels from a ConQuest system file.
Usage
sysToDimLabels(mySys, myWarn = TRUE)
Arguments
mySys |
An R object of class ConQuestSys, returned by the function conquestr::ConQuestSys. |
myWarn |
a bool indicating whether a warning should be printed if there are no dimension labels. |
Value
a data frame.
See Also
conquestr::sysToBMatrixDf()
sysToItemDifDf
Description
Creates a data frame that includes the common item parameter estimates from two (or more) system files (e.g., a DIF analysis).
Usage
sysToItemDifDf(listOfSysFiles, mySuffixes, myDims = "all")
Arguments
listOfSysFiles |
A list of system files returned from conquestr::ConQuestSys |
mySuffixes |
a vector of strings specifying the names for the two groups being analysed,
e.g., if the two system files are an analysis of boys and girls, the vector may be |
myDims |
A string specifying if all or specific dimensions should be included. The default is "all", Specific dimensions are specified by the label "D1" for dimensions 1 etc. |
Value
A data frame object.
See Also
conquestr::plotDif ()
sysToItemLabels
Description
Gets item labels from a ConQuest system file.
Usage
sysToItemLabels(mySys, myWarn = TRUE)
Arguments
mySys |
An R object of class ConQuestSys, returned by the function conquestr::ConQuestSys. |
myWarn |
a bool indicating whether a warning should be printed if there are no item labels. |
Value
a data frame.
See Also
conquestr::sysToBMatrixDf()
sysToItems
Description
Read an R object of class ConQuestSys and create a labelled representation of the B matrix (scoring matrix). This maps item response categories to items and dimensions.
Usage
sysToItems(mySys, myDims)
Arguments
mySys |
An R object of class ConQuestSys, returned by the function conquestr::ConQuestSys |
myDims |
A string specifying if all or specific dimensions should be included. The default is "all", Specific dimensions are specified by the label "D1" for dimensions 1 etc. |
Value
A data frame containing R the labelled B matrix.
See Also
conquestr::sysToItemDifDf()
testInfoAtTheta
Description
Calculates test information at a value of theta given a list of matricies of item parameters for one or more items.
Usage
testInfoAtTheta(myItems, theta)
Arguments
myItems |
A list of matrices of item parameters of the structure used in |
theta |
a number. |
Examples
anItem <- matrix(c(0,0,0,1,1,1,0,1), nrow = 2, byrow = TRUE)
testInfoAtTheta(list(anItem), 0)
testInfoOverTheta
Description
Calculates test information over a range of theta given a list of matricies of item parameters for one or more items. Returns a data frame with item information at a discrete set of values of theta. This is useful for plotting test information functions.
Usage
testInfoOverTheta(myItems, minTheta = -6, maxTheta = 6, stepTheta = 0.1)
Arguments
myItems |
a list of item parameters of the structure used in |
minTheta |
The smallest value of ability PDF to calculate info and to plot. Defaults to -6. |
maxTheta |
The largest value of ability PDF to calculate info and to plot. Defaults to 6. |
stepTheta |
The increment to iterate over the ability PDF. Defaults to 0.01. |
Examples
anItem <- matrix(c(0,0,0,1,1,1,0,1), nrow = 2, byrow = TRUE)
testInfoOverTheta(list(anItem))
thetaScore
Description
Return score (O-E) at theta. Used in estimation of theta by minimising raw score - expected score at theta
Usage
thetaScore(theta, responses, itemParams, perfAdjust = 0.3)
Arguments
theta |
a scalar value of theta. |
responses |
a vector of item responses for one case (can contain NA). Responses are in the same order as |
itemParams |
a list of item designs (each used in a call to |
perfAdjust |
the correction factor for zeros and perfects to be add/subtracted from the raw score. |
Value
a double, the score (O-E) at theta.
theta_ll
Description
returns the log of the likelihood of theta, given a vector of item responses, item parameters. Note that this is the simple ll - it is the continuing product of the response probabilities. It includes a hack, that will nudge the raw response to the first item to adjust for zeros and perfects. This should be updated to work with adjusted raw scores instead...
Usage
theta_ll(theta, responses, itemParams)
Arguments
theta |
a scalar value of theta. |
responses |
a vector of item responses (used in a call to |
itemParams |
a list of item designs (each used in a call to |
Value
a double, the log of the likelihood at theta..
thrstThrsh
Description
Generates Thurstonian Thresholds (sometimes called gammas) to an item. Thurstonian thresholds are the location on the trait/scale at which the cumulative probability of being in category k, or any higher category equals some probability (usually 0.5, the default). Thurstonian thresholds are considered a way of describing the difficulty of polytomously scored items and are usually the value used in visualisations like Wright maps. Thurstonian thresholds can only be calculated for items where response categories are scored such that each category can be placed in an order increasing scores (e.g., no ties as per the Ordered Partition model)
Usage
thrstThrsh(myItem, threshP = 0.5, minTheta = -20, maxTheta = 20, convC = 1e-05)
Arguments
myItem |
A matrix of parameters for a single item of the structure used in |
threshP |
The probability at which the threshold is calculated (defaults to the usual value of 0.5) |
minTheta |
The lower-bound starting value of the split-half search used to find the threshold for the category. |
maxTheta |
The upper-bound starting value of the split-half search used to find the threshold for the category. |
convC |
The convergence criteria used to determine when the threshold has been found. The difference between
|
Value
A k-1 by 1 matrix with Thurstonian thresholds for this item. Values are NA when the threshold cannot be calculated.
Examples
myItem <- matrix(
c(
0, -0.58 , 0 , 1, # delta+tau thurst thresh (gamma)
1, -0.58 , 0.776 , 1, # 0.196 -1.14
2, -0.58 , -0.697 , 1, # -1.277 -0.93
3, -0.58 , -0.629 , 1, # -1.209 -0.64
4, -0.58 , 0.55 , 1 # -0.03 0.25
), ncol =4, byrow=TRUE
)
thrstThrsh(myItem)
transformPvs
Description
Helper function to Transform PVs onto a new metric (e.g., PISA Mean = 500, SD = 100). Uses the method described in the PISA 2012 technical manual.
Usage
transformPvs(data, mT = 0, sdT = 1, weights = 1)
Arguments
data |
A data frame or matrix that contains the PVs |
mT |
The desired mean of the PVs |
sdT |
The desired sd of the PVs |
weights |
a vector of weights, the same length as |
Value
a List of transformed PVs with as many elements as PVs were listed in 'x'.
writeImportXsi
Description
Writes a fixed width text file in the format required for the
ACER ConQuest command and argument import anchor_xsi. Can also be used
for initial values, though caution should be used with the interpretation
of the argument lconstraint which should relate to the model of interest
ACER ConQuest
Currently only works with implicit variables. Explicit variables may be added in the future.
Usage
writeImportXsi(items, bmatix = 1L, lconstraint = "none", file)
Arguments
items |
a list of item matrices |
bmatix |
either the integer 1L for a unidimensional model, or a matrix, items by dimensions with 1L representing that the item in on this dimension, and a 0 otherwise. |
lconstraint |
the identification constraint in use, one of "none", "items", or "cases". |
file |
a path and filename to write file to disk. #' @return invisibly returns path of file written to disk) |
See Also
simplef(), genResponses(), browseVignettes("conquestr")
Examples
myItem <- matrix(c(0, 0, 0, 0, 1, 1, 0, 1), ncol = 4, byrow = TRUE)
myItems <- list(myItem, myItem)
myItems[[2]][2, 2] <- -1 # make the second item delta equal to -1
myResponses <- genResponses(abilities = rnorm(100), itemParams = myItems)
zapNulls
Description
Zaps NULL values embedded in ConQuest data objects.
Usage
zapNulls(x)
Arguments
x |
a data frame. |
Value
x.
zapSystemMissing
Description
Coerce ConQuest system missing values to NA. Note this is very slow and users should use the internal function conquestr::replaceInDataFrame where possible.
Usage
zapSystemMissing(x)
Arguments
x |
a data frame. |
Value
x