data_ctt: Example data (CTT)

In mmansolf/TSI: Custom mice Functions for True Score Imputation

Example data (CTT)

Description

Example data for true score imputation under classical test theory (CTT). Under the data-generating model, two groups (y=0 and y=1) were simulated using normal distributions with mean and variance equal to 1 for y=0 and equal to 1.5 for y=1. Normal measurement error was then added to each group corresponding to reliability (ratio of true to observed score variance) of .6.

Usage

data_ctt

Format

A data frame with two variables:

w

An observed scoregenerated under CTT

y

A dummy variable indicating group membership

Details

See below for data-generating code.

See vignette('TSI') or example(TSI) for example usage.

set.seed(0)
n=1000 #sample size
ratio=0.6 #ratio of true score variance to error variance; squared reliability coefficient
d=0.5 #mean difference
nimpute=10 #number of "posterior" draws of true score from modified conditional distribution of w
meanX=1 #mean of true score
meanW=1 #mean of observed score
varX=1 #variance of true score
varW=1 #variance of observed score

x1=rnorm(n,meanX,sqrt(varX))
e1=rnorm(n,0,sqrt(varX*(1-ratio)/ratio))
w1=x1+e1
x2=rnorm(n,meanX+d*sqrt(varX),sqrt(varX))
e2=rnorm(n,0,sqrt(varX*(1-ratio)/ratio))
w2=x2+e2
#into the data frame
w=c(w1,w2)
y=c(rep(0,n),rep(1,n))
data_ctt=data.frame(w,y)

mmansolf/TSI documentation built on Aug. 29, 2023, 2:38 a.m.