ABSTRACT
This chapter focuses on empirically testing the specialization hypothesis, using several data sources. The specialization hypothesis claims that as individual offenders age and continue to commit crimes, they become more likely to commit the same type of crime on successive offenses. Offenders show a great deal of versatility by committing different crimes for subsequent offenses. The bail decision-making study data are particularly useful for testing specialization among offenders because they contain substantial information on the arrest histories of the offenders in the sample and permit a direct test of the interaction effect of age and prior criminal activity. The Seattle Youth Survey (SYS) data provide a considerably different source of information on which to evaluate individuals and their specialization in offending. The approach taken in analyzing the SYS is to test whether individuals fall into different latent classes of offenders—personal, property, or nondelinquents.
