Stratified DIF Variance

Calculation of stratified DIF variance

Usage

dif.strata.variance(dif, se.dif, itemcluster)

Arguments

dif

Vector of uniform DIF effects

se.dif

Standard error of uniform DIF effects

itemcluster

Vector of item strata

Value

A list with following entries:

stratadif

Summary statistics of DIF effects within item strata

weighted.DIFSD

Weighted DIF standard deviation

unweigted.DIFSD

DIF standard deviation

References

Longford, N. T., Holland, P. W., & Thayer, D. T. (1993). Stability of the MH D-DIF statistics across populations. In P. W. Holland & H. Wainer (Eds.). Differential Item Functioning (pp. 171-196). Hillsdale, NJ: Erlbaum.

See also

See dif.logistic.regression for examples.