Whether individual differences are treated as categorical or continuous has consequences for theory, assessment, classification, and research in criminal justice. Paul Meehl's (1995) taxometric method allows investigators to test between these two competing structural models. This article provides an overview of the method's inferential framework and data-analytic procedures. Because guidelines for implementing taxometric analyses and interpreting their results have received little research attention, investigators are encouraged to adopt an empirically grounded approach to taxometric analysis rather than following conventions or relying on personal opinion. The guidance afforded by Monte Carlo studies, including the two reported here, can be supplemented by simulating comparison data. This empirically grounded approach, described and illustrated below, helps to implement the taxometric method effectively and to draw valid conclusions.
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