plotDIFLogistic: Function for characteristic curve of 2PL logistic DIF model

Description Usage Arguments Details Author(s) Examples

View source: R/plotDIFLogistic.R

Description

Plots characteristic curve of 2PL logistic DIF model

Usage

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plotDIFLogistic(data, group, type = "both", item, item.name,
IRT = F, p.adjust.method = "none", purify = F)

Arguments

data

numeric: the data matrix. See Details.

group

numeric: the vector of group membership. See Details.

type

character: a character string specifying which DIF effects must be tested. Possible values are "both" (default), "udif" and "nudif". See Details.

item

numeric: number of item to be plotted

item.name

character: the name of item.

IRT

logical: if IRT parameterization (TRUE, default) or classic logistic parameterization (FALSE) may be applied.

p.adjust.method

character: the acronym of the method for p-value adjustment for multiple comparisons. See Details.

purify

logical: if item purification may be applied.

Details

This function plots characteristic curve of 2PL logistic DIF model.

Author(s)

Adela Drabinova
Institute of Computer Science, The Czech Academy of Sciences
Faculty of Mathematics and Physics, Charles University
[email protected]

Patricia Martinkova
Institute of Computer Science, The Czech Academy of Sciences
[email protected]

Examples

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## Not run: 
# loading libraries
library(difNLR, difR)

 # loading data based on GMAT
data(GMAT, package = "difNLR")
data  <- GMAT[, 1:20]
group <- GMAT[, 21]

# Characteristic curve by logistic regression model
plotDIFLogistic(data, group, item = 1)

# Characteristic curve by logistic regression model using scaled score
plotDIFLogistic(data, group, item = 1, IRT = T)

## End(Not run)

patriciamar/ShinyItemAnalysis documentation built on Jan. 14, 2019, 8:53 p.m.