Research Reports

The Influence of the Psychometric Quality of a Test When Making Admission Decisions (PR 18-04)

This study employed a data simulation to evaluate the impact of a strategy to reduce test length by including only high-quality test questions, where quality was defined by a statistical indicator of the degree to which a question distinguishes between more and less able test takers. The impact of this strategy on the rank ordering of simulated test takers according to their total test score was evaluated, as was the predictive validity and classification accuracy of scores based on the shorter tests. Empirical data from an undergraduate admission test was used to further investigate the effect of this strategy. Results showed that reducing test length by as much as half had no serious effects on the estimate of test-taker ability, whereas shortening the test beyond that point was problematic. Furthermore, the empirical data showed that although the reliability and criterion-related validity (i.e., the relationship of the test score to the outcome of interest) may not be seriously affected by shortening the test, the reduced score range of the shorter test may be too limited to differentiate between candidates based on test scores. In addition, the shorter test may not adequately cover the required content. Finally, the use of score bands in admission testing was 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.