HOW MANY LATENT CLASSES OF DELINQUENT CRIMINAL CAREERS - RESULTS FROMMIXED POISSON REGRESSION-ANALYSES/

This article reviews questions about different categories of criminal careers, summarizes Poisson latent class regression models, describes procedures for evaluating the optimal number of latent classes, and ap plies this methodology to data from male cohorts taken from the cities of London, Philadelphia, and Racine. Four latent classes of offending careers is an appropriate number for the London cohort, but five clas ses can be justified for the Philadelphia data. In the case of the Rac ine cohorts, five classes may be detected for the 1942 and 1955 cohort s but only four for the 1949 cohort. Despite the varying numbers of la tent offending classes, there clearly is a small number of typical age patterns.