Research Reports

Marginalized Measurement Variance Modeling and Bayes Factor Testing (RR 16-06)

Among the assumptions that should be met when applying an item response theory (IRT) model to the analysis of test data is measurement invariance. Measurement invariance requires that, after controlling for a test taker’s proficiency, group membership have no effect on the probability that that test taker will answer a test question correctly. Groups may be defined on the basis of many factors, including gender, race/ethnicity, and citizenship.

This research study proposes and evaluates a new method for detecting violations of the measurement invariance assumption. The method is evaluated through both data simulation and application to actual responses to an international survey. The results obtained by the proposed method are also compared to those obtained using the Mantel–Haenszel statistic, the industry standard for group membership comparisons. Promising results are reported, and plans for extended research are discussed.

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Evidence to Support Validity Claims for Using LSAT Scores...

Law School Admission Test (LSAT) scores provide a standard measure of an applicant’s proficiency in a well-defined set of important skills associated with success in law school coursework. LSAT scores are also a strong predictor of first-year grades (FYG) and cumulative grade point average (CGPA) in law school. The most recent correlational study of LSAT results (2019) shows that LSAT scores are far superior to undergraduate grade point average (UGPA) in predicting FYG...

Understanding and Interpreting Law School Enrollment Data...

The Law School Admission Council (LSAC) has a long-standing commitment to diversity, equity, and inclusion in legal education and in the legal profession. In line with its mission to promote quality, access, and equity in legal education, LSAC is providing this report, Understanding and Interpreting Law School Enrollment Data: A Focus on Race and Ethnicity, to help law schools, admission professionals, and other legal education stakeholders understand how we are measuring who is the pipeline.