irtrees (version 1.0.0)

VerbAgg2: Verbal Aggression Data, Dichotomized Items

Description

Item responses to a questionaire on verbal aggression. These data are used throughout De Boeck and Wilson, Explanatory Item Response Models (Springer, 2004) to illustrate various forms of item response models.

Format

A data matrix with 316 persons, 24 three-category items, and two person covariates (trait anger and gender).

References

De Boeck and Wilson (2004), Explanatory Item Response Models, Springer.

Examples

# NOT RUN {
str(VerbAgg2)
mapping <- cbind(c(1,1,1), diag(3))
str(VerbAgg2T <- exogenize(VerbAgg2[,-c(1,2)], mapping,
	endnode=rep(1:3, 8)))
# }