kcirt.model: Create k-Cube Thurstonian IRT Model

In kcirt: k-Cube Thurstonian IRT Models

Description

Create a k-Cube Thurstonian IRT Model skeleton.

Usage

kcirt.model(constructMap.ls, qTypes, data = NULL, Y = NULL, mu = 0, mxLambda = NULL, 
covEta = 1, covShocks = 1, deltaType=1)

Arguments

constructMap.ls	How the constructs map to the items. A list of vectors, each vector representing a block (question in the instrument); each element of a vector giving the construct index.
qTypes	Is a question to be fully ranked or most/least format. A character vector whose length is the number of blocks. Each element in {"R", "M"}. Note that only accepts 'R' when corresponding block has 3 or 2 items.
data	Data matrix. The number of columns is the number of observational units, the number of rows is the total number of items.
Y	Response cohort matrix, each element in {NA,0,1}.
mu	True item means. A real-valued vector whose length is the total number of items.
mxLambda	True hyperparameters. A real-valued square matrix, or a vector. If vector, mxLambda is assumed to be diagonal (no item crosstalk) – vector is recycled
covEta	True covariance of states. A square, symmetric real-valued matrix.
covShocks	True covariance of shocks. A square, symmetric real-valued matrix.
deltaType	Tell function in what pattern items are compared. Scalar. Directly affects structure of the Delta matrix. Currently one of two integer values. 1 is default. 2 is that implied by Brown and Maydeau-Oliveras.

Value

A kcirt model. A named list of class “kcube.irt.model”.

Author(s)

Dave Zes, Korn/Ferry International

Examples

constructMap.ls <- list(
c(1,2),
c(2,3),
c(1,3)
)

qTypes <- rep("R", length(constructMap.ls))

mod <- kcirt.model(constructMap.ls=constructMap.ls, qTypes=qTypes, mxLambda=NULL)

## view contents
mod

Example output

Loading required package: mvtnorm
Loading required package: snowfall
Loading required package: snow
Loading required package: corpcor
$constructMap.ls
$constructMap.ls[[1]]
[1] 1 2

$constructMap.ls[[2]]
[1] 2 3

$constructMap.ls[[3]]
[1] 1 3


$qTypes
[1] "R" "R" "R"

$mxData
NULL

$Y
NULL

$Z
NULL

$Yisna
NULL

$nBlocks
[1] 3

$nuc
[1] 3

$ns
[1] 2 2 2

$nks
[1] 1 1 1

$mxDelta
     [,1] [,2] [,3] [,4] [,5] [,6]
[1,]   -1    1    0    0    0    0
[2,]    0    0   -1    1    0    0
[3,]    0    0    0    0   -1    1

$mxSlot
     [,1] [,2] [,3]
[1,]    1    0    0
[2,]    0    1    0
[3,]    0    1    0
[4,]    0    0    1
[5,]    1    0    0
[6,]    0    0    1

$mu
[1] 0 0 0 0 0 0

$mxLambda
     [,1] [,2] [,3] [,4] [,5] [,6]
[1,]    1    0    0    0    0    0
[2,]    0   -1    0    0    0    0
[3,]    0    0    1    0    0    0
[4,]    0    0    0   -1    0    0
[5,]    0    0    0    0    1    0
[6,]    0    0    0    0    0   -1

$covEta
     [,1] [,2] [,3]
[1,]    1    0    0
[2,]    0    1    0
[3,]    0    0    1

$covShocks
     [,1] [,2] [,3] [,4] [,5] [,6]
[1,]    1    0    0    0    0    0
[2,]    0    1    0    0    0    0
[3,]    0    0    1    0    0    0
[4,]    0    0    0    1    0    0
[5,]    0    0    0    0    1    0
[6,]    0    0    0    0    0    1

$covStochastic
     [,1] [,2] [,3]
[1,]    2    0    0
[2,]    0    2    0
[3,]    0    0    2

$mxSigma
     [,1] [,2] [,3]
[1,]    4    1    1
[2,]    1    4    1
[3,]    1    1    4

$Qid
$Qid[[1]]
[1] 1 1

$Qid[[2]]
[1] 2 2

$Qid[[3]]
[1] 3 3


$mxLambdaCTinfo
     [,1] [,2] [,3] [,4] [,5] [,6]
[1,] "S"  "WF" "BF" "BF" "BT" "BF"
[2,] "WF" "S"  "BT" "BF" "BF" "BF"
[3,] "BF" "BT" "S"  "WF" "BF" "BF"
[4,] "BF" "BF" "WF" "S"  "BF" "BT"
[5,] "BT" "BF" "BF" "BF" "S"  "WF"
[6,] "BF" "BF" "BF" "BT" "WF" "S" 

$constructSlotKey
[1] 1 2 3

attr(,"class")
[1] "kcube.irt.model"

kcirt documentation built on May 2, 2019, 4:16 a.m.