Single administration (beta-binomial) estimates for the raw agreement index p and the corrected-for-chance kappa index in mastery testing are compared with those based on two test administrations in terms of estimation bias and sampling variability. Bias is about 2.5 percent for p and 10 percent for kappa. (Author/RL)

Results from the Maryland School Performance Assessment Program for 5,392 elementary school students and from the Comprehensive Tests of Basic Skills (multiple choice) for a national sample are used to explore local item independence (LID) of test items. Some strategies are suggested for measuring LID in performance assessments. (SLD)