Corrected bugs + TAM dif analysis

RProject/dif.R

@@ -0,0 +1,27 @@
+library(mirt)
+
+pcm_analysis <- function(df=NULL,treatment='TT',irtmodel='PCM2',method='MML') {
+  nbitems <- sum(sapply(1:20,function(x) paste0('item',x)) %in% colnames(df))
+  resp <- df[,sapply(seq(1,nbitems),function(x) paste0('item',x))]
+  if (method=='MML') {
+    tam1 <-  tam.mml(resp=resp,Y=df[,treatment],irtmodel = irtmodel,est.variance = T,verbose=F)
+  }
+  if (method=='JML') {
+    tam1 <- tam.jml(resp=resp,group=1+df[,treatment])
+  }
+  if (method!='MML' & method!='JML') {
+    stop('Invalid method. Please choose among MML or JML')
+  }
+  return(tam1)
+}
+
+dff <- read.csv(file = '/home/corentin/Documents/These/Recherche/Simulations/Data/DIF/N50/scenario_5A_50.csv')
+dfff <- dff[dff$replication==1,]
+facets <- dfff$TT
+dfff$item2_noTT <- NA
+dfff$item2_TT <- NA
+dfff[dfff$TT==0,]$item2_noTT <- dfff[dfff$TT==0,"item2"]
+dfff[dfff$TT==1,]$item2_TT <- dfff[dfff$TT==1,"item2"]
+
+mml.mod <- tam.mml(resp=dfff[,c('item1','item2_noTT','item2_TT',"item3","item4")],Y=dfff$TT,constraint='cases'
+                     ,irtmodel = "PCM2",est.variance = T,verbose=F)