Wednesday, October 23, 2019
Richard Gardiner (AccessLex), Understanding the Impact of Range Restriction on LSAT Correlation Studies:
Several empirical studies have found a link between LSAT score and bar exam performance. AccessLex is currently seeking to gain a better understanding of factors, both LSAT score and others, that influence bar passage through the Bar Exam Success Initiative in partnership with LSSSE. So far, our work suggests that there may be a tenuous relationship between the LSAT and bar exam outcome. At 5 of the 19 schools we studied, LSAT scores had some predictive relationship to bar exam performance. These relationships usually faded by the second year of law school, being overshadowed by law school grades. At the other schools, no relationships between LSAT scores and bar exam performance were found. However, there is a reason why the relationship between LSAT and bar passage may be difficult to detect—that being the influence of range restriction. ...
As before, you only accept students with a 155 or higher. But you have never been able to yield those students above 165. You can guess what happens—the correlation drops even further (though very small changes do not necessarily lead to changes lower correlations). Figure 3 shows the new graph, which results in a correlation of 0.14.
I have built an interactive web application where you can filter that same 5,000 simulated individuals. You can view it here: https://accesslex.shinyapps.io/range_restriction/. All graphs and the app were built using R. If you have any questions, contact us at firstname.lastname@example.org