detect.index {sirt}

Calculation of the DETECT and polyDETECT Index

Description

This function calculated the DETECT and polyDETECT index (Stout, Habing, Douglas & Kim, 1996; Zhang & Stout, 1999a; Zhang, 2007). At first, conditional covariances have to be estimated using the ccov.np function.

Usage

detect.index(ccovtable, itemcluster)

Arguments

ccovtable

A value of ccov.np.

itemcluster

Item cluster for each item. The order of entries must correspond to the columns in data (submitted to ccov.np).

References

Stout, W., Habing, B., Douglas, J., & Kim, H. R. (1996). Conditional covariance-based nonparametric multidimensionality assessment. Applied Psychological Measurement, 20, 331-354.

Zhang, J., & Stout, W. (1999a). Conditional covariance structure of generalized compensatory multidimensional items. Psychometrika, 64, 129-152.

Zhang, J., & Stout, W. (1999b). The theoretical DETECT index of dimensionality and its application to approximate simple structure. Psychometrika, 64, 213-249.

Zhang, J. (2007). Conditional covariance theory and DETECT for polytomous items. Psychometrika, 72, 69-91.

See Also

For examples see conf.detect.