Learn_2PL_IRT

###install.packages ("MPsychoR")
###install.packages("ltm")
library(MPsychoR)
library (ltm)

## Warning: package 'ltm' was built under R version 4.2.3

## Loading required package: MASS

## Loading required package: msm

## Warning: package 'msm' was built under R version 4.2.3

## Loading required package: polycor

## Warning: package 'polycor' was built under R version 4.2.3

data("RWDQ")
##str(RWDQ)
fit2pl1 <- ltm (RWDQ ~ z1)

head (coef (fit2pl1))

##            Dffclt     Dscrmn
## wdq_22 -9.4899518  0.1235779
## wdq_23  1.0673713 -0.7324307
## wdq_24  0.3893959 -0.8157724
## wdq_25  1.4559338 -1.5614798
## wdq_26  2.1251683 -0.6637341
## wdq_27  0.5713899 -1.1531809

write.csv(RWDQ, "RWDQ")

getwd()

## [1] "C:/Users/Jerome/Documents/0000_Work_Files/0000_Morgan/000_Psychometrics_Courses/PSYM_540/HW_Exercise_3A"