## Workshop on catR - The Psychometrics Centre,
## Cambridge University, June 10th, 2014

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### R script for Session 3 ###
##############################

### Load catR package
require(catR)

### Set the directory where the item bank is stored
setwd("c:/Users/David/Desktop/")

### Load 'IQ' item bank
bank <- read.table("IQ.txt",header = TRUE)
bank <- as.matrix(bank)

### CAT design:
## two starting items, most informative at theta = c(-1,1)
startList <- list(nrItems = 2, theta = 0, halfRange = 1)

## next item selection by 'MFI', EAP ad-interim proficiency estimation
testList <- list(method = "EAP", itemSelect = "MFI")

## stop after 10 items
stopList <- list(rule = "length", thr = 10)

## final proficiency estimation
finalList <- list(method = "ML")


### generation of a CAT response pattern
res <- randomCAT(trueTheta = 0, itemBank = bank, start = startList, 
test = testList, stop = stopList, final = finalList)

## displaying the 'full' (bruto) output
str(res)

## display of the output
res

## graphical display of the output
plot(res)
plot(res,ci=TRUE)