Modelling Heaped Duration Data: An Application to Neonatal Mortality

In 2005, the Indian Government launched a conditional cash-incentive program to en- courage institutional delivery. This paper studies the e ects of the program on neonatal mortality using district-level household survey data. We model mortality using survival analysis, paying special attention to the substantial heaping present in the data. The main objective of this paper is to provide a set of sucient conditions for identi cation and consistent estimation of the baseline hazard accounting for heaping and unobserved heterogeneity. Our identi cation strategy requires neither administrative data nor mul- tiple measurements, but a correctly reported duration and the presence of some at segments in the baseline hazard which includes this correctly reported duration point. We establish the asymptotic properties of the maximum likelihood estimator and pro- vide a simple procedure to test whether the policy had (uniformly) reduced mortality. While our empirical ndings do not con rm the latter, they do indicate that accounting for heaping matters for the estimation of the baseline hazard.