For statistical inference on regression models with a diverging number of covariates, the existing literature typically makes sparsity assumptions inverse Fisher information matrix. Such assumptions, however, are often violated under Cox proportion hazards models, leading to biased estimates under-coverage confidence intervals. We propose modified debiased lasso method, which solves series quad...

PURPOSE Cyclooxygenase-2 (COX-2) plays important roles in the modulation of apoptosis, angiogenesis, immune response, and tumor invasion. Elevated COX-2 expression has been reported to be correlated with reduced survival after radiotherapy. This study examined whether genetic variations in the COX-2 gene are associated with different survival in inoperable locally advanced non-small cell lung c...

We show that the nonparametric maximum likelihood estimate (NPMLE) of the regression coefficient from the joint likelihood (of the regression coefficient and the baseline survival) works well for the Cox proportional hazards model with left-truncated and interval-censored data, but the NPMLE may underestimate the baseline survival. Two alternatives are also considered: first, the marginal likel...

GOFCOX is a user-friendly FORTRAN program for assessing the adequacy of the Cox proportional hazards model. The underlying methodology is based on the comparison of the maximum partial likelihood estimator and a weighted parameter estimator. The latter is the root to an estimation equation that assigns varying weights to the individual contributions to the partial likelihood score function. The...

The regular maximum partial likelihood estimator is biased when the covariates in the Cox proportional hazards model are measured with error, unless the measurement errors tend to zero. Although several alternative estimators have been proposed, theoretical justifications for them are lacking. We try to fill this gap by showing that the corrected maximum partial likelihood estimator proposed by...

We introduce the R package CPHshape, which computes the effect parameters and the nonparametric maximum likelihood estimator of a shape constrained baseline hazard in the Cox proportional hazards model. The functionality of the package is illustrated using reproducible examples which are based on simulated data.