Parametric and Parametrically Smoothed Distribution-Free Proportional Hazard Models with Discrete Data

This paper discusses discrete time proportional hazard models and suggests a new class of flexible hazard functions. Explicitly modeling the discreteness of data is important since standard continuous models are biased; allowing for flexibility in the hazard estimation is desirable since strong parametric restrictions are likely to be similarly misleading. Simulation compare continuous and discrete models when data are generated by grouping and demonstrate that simple approximations recover underlying hazards well and outperform nonparametric maximum likelihood estimates in term of mean squared error.     

Nonparametric regression using local kernel estimating equations for correlated failure time data

We study nonparametric regression for correlated failure timedata. Kernel estimating equations are used to estimate nonparametriccovariate effects. Independent and weighted-kernel estimatingequations are studied. The derivative of the nonparametric functionis first estimated and the nonparametric function is then estimatedby integrating the derivative estimator. We show that the nonparametrickernel estimator is consistent for any arbitrary working correlationmatrix and that its asymptotic variance is minimized by assumingworking independence. We evaluate the performance of the proposedkernel estimator using simulation studies, and apply the proposedmethod to the western Kenya parasitaemia data.     

Complete nucleotide sequence and gene organization of the mitochondrial genome of Paa spinosa (Anura: Ranoidae)

The mt genome of Paa spinosa (Anura: Ranoidae) is a circular molecule of 18,012 bp in length, containing 38 genes (including an extra copy of tRNA-Met gene). This mt genome is characterized by three distinctive features: a cluster of rearranged tRNA genes (LTPF tRNA gene cluster), a tandem duplication of tRNA-Met gene (Met1 and Met2), and distinct repeat regions at both 5′ and 3′-sides in the control region. Comparing the locations and the sequences of all tRNA-Met genes among Ranoidae, and constructing NJ tree of the nucleotide of those tRNA-Met genes, we suggested a tandem duplication of tRNA-Met gene can be regarded as a synapomorphy of Dicroglossinae. To further investigate the phylogenetic relationships of anurans, phylogenetic analyses (BI, ML and MP) based on the nucleotide dataset and the corresponding amino acid dataset of 11 protein-coding genes (except ND5 and ATP8) arrived at the similar topology.