A META ANALYSIS OF THE VALIDITY OF PREDICTORS OF PERFORMANCE IN LAW SCHOOL

Although there is considerable evidence that the Law School Admission Test (LSAT) and the undergraduate grade-point average (UGPA) have a useful degree of predictive validity, there is also a large variation in the magnitude of the coefficients across schools. Understanding this variation has important implications for the use and interpretation of results of a validity study conducted at an individual school. A meta analysis of the validity results and data on applicants to 154 law schools was conducted in an effort to better understand this observed variation. The standard deviation (SD) on the LSAT and the correlation between the LSAT and UGPA for accepted students at each law school accounted for 58.5% of the between-school variance in the multiple correlations of these two predictors with first-year average grade in law school. Sampling error accounted for an additional 12% of the variance. Hence, only a small fraction of the between-school variability in validities remains to be explained by other statistical artifacts of situational specificity factors. Mean validities and 90% credibility values for four adjustment procedures are reported as are the mean observed validities for different combinations of predictors.