itemanalysis1 | R Documentation |
Classicial Test Theory Item Analysis for Multiple-Choice Test Items
itemanalysis1(data, key, options, ngroup = ncol(data) + 1, correction = TRUE, span.par=.3, verbose = T)
data |
a data frame with N rows and m columns, with N denoting the number of subjects and m denoting the number of items. |
key |
a vector of answer key with a length of m |
options |
a vector of response options for the test such as c("A","B","C","D") |
ngroup |
number of score groups to be use for plotting the item trace lines |
correction |
TRUE or FALSE. If it is TRUE, then an adjustment is made for point-biserial correlation. |
span.par |
a smoothing parameter to pass to ggplots when creating empirical ICCs |
verbose |
TRUE or FALSE. If it is TRUE, text output is printed. |
To be added later.
plots |
a list object storing the item trace line plots for each item |
item.stat |
a matrix of basic item statistics |
dist.sel |
a matrix of distractor selection proportion statistics |
dist.disc |
a matrix of corrected point-biserial statistics for distractors |
dist.disc |
a matrix of corrected biserial statistics for distractors |
Cengiz Zopluoglu
itemanalysis2
for classical item analysis of polytomously scored items
## Not run: data(dichotomous) head(dichotomous) str(dichotomous) # Key response vector key <- c("A","D","C","B","C","B","C","D","A","D","C","A","D","C","A", "B","D","B","A","C","A","A","C","B","C","B","D","A","A","A", "C","B","B","A","B","D","D","A","D","C","D","A","B","B","C", "D","B","C","C","B","D","A","C","B","A","D") # Use itemanalysis1 function to run the item analysis # In order to reduce running time for the example below, # I specify "data=dichotomous[,1:10]", so it only analyze the # first 10 items. # You should specify "data=dichotomous" to analyze based on 56 items. item.analysis <- itemanalysis1(data=dichotomous[,1:10], key=key, options=c("A","B","C","D"), ngroup=10, correction=FALSE) item.analysis$item.stat item.analysis$dist.sel item.analysis$dist.disc item.analysis$plots[[1]] # Item Trace Line for the first item item.analysis$plots[[2]] # Item Trace Line for the second item item.analysis$plots[[3]] # Item Trace Line for the third item item.analysis$plots[[4]] # Item Trace Line for the fourth item item.analysis$plots[[5]] # Item Trace Line for the fifth item item.analysis$plots[[6]] # Item Trace Line for the sixth item item.analysis$plots[[7]] # Item Trace Line for the seventh item item.analysis$plots[[8]] # Item Trace Line for the eigth item item.analysis$plots[[9]] # Item Trace Line for the ninth item item.analysis$plots[[10]] # Item Trace Line for the tenth item ## End(Not run)
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