Since the early 1980s, the econometric analysis of duration variables has become widespread. This chapter provides an overview of duration analysis, with an emphasis on the specification and identification of duration models, and with special attention to models for multiple durations. Most of...

We model credit rating histories as continuous-time discrete-state Markov processes. Infrequent monitoring of the debtors' solvency will result in erroneous observations of the rating transition times, and consequently in biased parameter estimates. We develop a score test against such...

We prove identification of dependent competing risks models in which each risk has a mixed proportional hazard specification with regressors, and the risks are dependent by way of the unobserved heterogeneity, or frailty, components. We show that the conditions for non-parametric identification...