Research Reports

The Probability of Exceedance as a Nonparametric Person-Fit Statistic for Tests of Moderate Length (RR 13-06)

In this report we present a measure to identify unlikely patterns of correct/incorrect answers to test questions (commonly referred to as items). Some examples of why such patterns may occur include the misinterpretation of questions, item preknowledge, answer copying, or guessing behavior. The proposed measure is the probability of exceedance (PE). PE provides information about the probability of a correct/incorrect answer pattern, conditional on the test taker’s total score. Although this concept is not new, it is hardly if ever applied in practice.

In this report we show how the PE of a response vector can be computed and how misfitting response patterns are detected. A simulation study is conducted to investigate the robustness of this procedure.

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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.