In some practical applications of transition models there is a natural limit on the duration of some state. An important example is the Youth Training Scheme (YTS), which is normally limited to two years. The authors modify the usual competing risks model for this case and derive a diagnostic...

This study investigates the routes by which young people develop patterns of drug-using and offending behaviour. Survey data are used to assess the gateway effect — the tendency for soft drug use to lead to subsequent hard drug use and criminal activity. We argue that apparently strong gateway...