check.reliability {mokken}R Documentation

Compuation of reliability statistics

Description

Returns a list of three reliability statistics: Molenaar Sijtsma (1984, 1988) statistic (a.k.a rho), Cronbach's (1951) alpha, and Guttman's (1945) lambda 2.

Usage

check.reliability(X)

Arguments

X matrix or data frame of numeric data containing the responses of nrow(X) respondents to ncol(X) items. Missing values are not allowed

Value

MS Molenaar Sijtsma statistic (a.k.a. rho).
alpha Cronbach's alpha
lambda.2 Lambda 2

Author(s)

L. A. van der Ark a.vdark@uvt.nl

References

Cronbach, L. (1951). Coefficient alpha and the internal structure of tests. Psychometrika, 16, 297-334.

Guttman, L. (1945). A basis for analyzing test-retest reliability. Psychometrika, 10,255-282.

Molenaar, I. W. and K. Sijtsma (1984). Internal consistency and reliability in Mokken's nonparametric item response model. Tijdschrift voor onderwijsresearch, 9, 257–268.

Molenaar, I. W. and K. Sijtsma (1988). Mokken's approach to reliability estimation extended to multicategory items. Kwantitatieve methoden, 9(28), 115-126.

Sijtsma, K. and I. W. Molenaar (1987). Reliability of test scores in nonparametric item response theory. Psychometrika, 52,79-97.

Van der Ark, L. A. (2007). Mokken scale analysis in R. Journal of Statistical Software. http://www.jstatsoft.org

Van der Ark, L. A. (2008). Computation of the Molenaar Sijtsma statistic. Manuscript submitted for publication

See Also

coefH, check.iio, check.monotonicity, check.pmatrix, check.restscore

Examples

data(acl)
Communality <- acl[,1:10]
check.reliability(Communality)

[Package mokken version 1.4 Index]