sim_gpcm {PP} | R Documentation |
This function returns an integer matrix of simulated responses under given item and person parameters.
sim_gpcm(thres, alpha, theta)
thres |
An numeric matrix which contains threshold parameters for each item. The first row must contain zeroes only! |
alpha |
A numeric vector, which contains the slope parameters - one parameter per item is expected. |
theta |
A numeric vector which contains person parameters. |
################# simulate GPCM ############################################### set.seed(1750) THRES <- matrix(c(-2,-1.23,1.11,3.48,1 ,2,-1,-0.2,0.5,1.3,-0.8,1.5),nrow=2) # slopes sl <- c(0.5,1,1.5,1.1,1,0.98) THRESx <- rbind(0,THRES) THETA <- rnorm(100) simdat_gpcm <- sim_gpcm(thres = THRESx,alpha = sl,theta = THETA) head(simdat_gpcm) ### simulate with a different number of categories THRES1 <- rbind(THRESx,c(NA,NA,NA,NA,1.7,1)) THRES1 # last 2 items have +1 category simdat_gpcm2 <- sim_gpcm(thres = THRES1,alpha = sl,theta = THETA) head(simdat_gpcm2) # check the maximum category apply(simdat_gpcm2,2,max)