mstDIF-Methods {mstDIF}

Methods for the mstDIF-class

Description

print and summary methods for objects of the mstDIF-class, as returned by mstDIF. See details for more information about the methods.

Usage

## S3 method for class 'mstDIF'
print(x, ...)

## S3 method for class 'mstDIF'
summary(object, DIF_type = "overall", ordered = TRUE, ...)

Arguments

x

an object of class mstDIF

...

other arguments passed to the method.

object

an object of class mstDIF

DIF_type

a string that should one or more of "overall", "uniform", "non-uniform", "all".

ordered

logical: should the summary be ordered according to the obtained p-values (in ascending order)?

Details

The print method prints some basic information about the mstDIF-class object.

The summary method computes a data frame with a row for each item that was included in the test. The columns are:

item

The name of the item

statistic

The value for the used statistic per item

p_value

The p-value per item

eff_size

An effect-size for the DIF-test, if applicable

Examples

## load data
data("toydata")

## fit 2PL model using mirt
mirt_model <- mirt::mirt(toydata$resp, model = 1)

## test DIF along a contiuous covariate
DIFtest <- mstDIF(mirt_model, DIF_covariate = toydata$group_cont,
method = "analytical")

## print
DIFtest

## summary
summary(DIFtest)