Research Reports

Estimating and Testing the Extended Testlet Model (RR 12-03)

A set of test questions (i.e., items) grouped around a common stimulus is often referred to as a testlet. Testlets are found on the Law School Admission Test in the Analytical Reasoning and Reading Comprehension sections. This research extends current testlet theory by identifying and modeling the relationship between testlet features and test-taker response behavior on testlets. Several estimation procedures are developed, and a small simulation study shows that the procedures evaluated produce similar results.

One of the purposes of this project is to select the testlet features with the best prediction properties using text mining. This requires estimating the testlet model in the presence of a very large number of testlets and respondents. To demonstrate the feasibility of the estimation methods, a large-scale example is computed using data from 49,256 test takers who were administered a subset from 594 items nested within 100 testlets.

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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.