Introducing a Bayesian Approach to Determining Degree of Fit With Existing Rorschach Norms

This article offers a new methodological approach to investigate the degree of fit between an independent sample and 2 existing sets of norms. Specifically, with a new adaptation of a Bayesian method, we developed a user-friendly procedure to compare the mean values of a given sample to those of 2 different sets of Rorschach norms. To illustrate our technique, we used a small, U.S. community sample of 80 adults and tested whether it resembled more closely the standard Comprehensive System norms (CS 600; Exner, 2003), or a recently introduced, internationally based set of Rorschach norms (Meyer, Erdberg, & Shaffer, 2007 ). Strengths and limitations of this new statistical technique are discussed.