We propose a simple and flexible framework for the crossing hazards problem. The method is not confined to two-sample problems, but it may also work with continuous exposure variables whose effect changes its sign atsome time point of the observed follow-up time. Penalized partial likelihood estimation relies upon the assumption of a smooth hazard ratio via low-rank basis splines with a conventional difference penalty to ensure smoothness, and additional ad-hoc penalties to obtain restricted estimates useful in the context of crossinghazards. The framework naturally also leads to statistical test which has good power for revealing a global effect under several alternatives, including crossing hazards. We provide results from a real-data analysis andfrom some simulations to illustrate empirically the performance of the proposed approach as compared to possiblealternatives.
|Numero di pagine||11|
|Rivista||Statistics in Medicine|
|Stato di pubblicazione||Published - 2010|
All Science Journal Classification (ASJC) codes
- Statistics and Probability