Our interest in the statistical modeling of data on the timing of
recidivism began in the mid 1970s when we were both junior members of
the eco- nomics department at the University of North Carolina. At that
time, methods of analyzing qualitative and limited variables were being
developed rapidly in the econometric literature, and we became
interested in finding a suitable application for these new methods. Data
on the timing of recidivism offered unique and interesting statistical
challenges, such as skewness of the distribution and the presence of
censoring. Being young and foolish, we decided it would be fun to try
something "really" difficult. And, being young and ignorant, we were
blissfully unaware of the con- current developments in the statistical
modeling of survival times that were then appearing in the
biostatistics, operations research, and criminological literatures. In
the course of some earlier research, we had learned that the North
Carolina Department of Correction had an unusually well-developed data
base on their inmates. We approached the Department and asked if they
would be interested in working with us to develop models that would
predict when their former charges would return to their custody. They
agreed because they were interested in using such models to evaluate
rehabilitative programs and alternative prison management systems and to
help project future prison populations.