[R] Error in finding factor scores/ person ability in item response theory

Dear R users, I have encountered some error in finding factor scores/ person ability in item response theory. I tried a few times using ltm and mirt package but it still gave me error. #TRY #1 - Fit GPCM model using ltm > irt_model <- gpcm(response_matrix) > irt_person_abilities <- fscores(ir

[R] Error in analysis of arguments of Rasch

Dear R users, I am using ltm and eRm package in analysing my polytomous data for fitting item response theory and Rasch model, respectively. I'm having a problem with the error as below; > library(eRm) > library(ltm) > HT <- read.csv("C:/Dropbox/Analysis R_2023/HT.csv") > response_columns <- HT[

[R] Error in analysis of Rasch using eRm package.

Dear R users, I am using eRm package in analysing my polytomous data as below Respondents = 277 people Item = 30 questions The data consists of 0,1,2,3 responses/answers. I'm having a problem in writing coding as below because I do not know what I should replace in each of the arguments. data.