Journal of Biometrics & Biostatistics

Stanley Xu

Publications

• Research Article
  Statistical Methods for Estimating Within-Cluster Effects for Clustered Poisson Data
  Author(s): Dexiang Gao, Gary K. Grunwald and Stanley XuDexiang Gao, Gary K. Grunwald and Stanley Xu
  
  Clustered Poisson data frequently appear in medical research. Interest often focuses on examination of an exposure effect within clusters. The objective of this paper is to compare the performance of six methods for estimating the exposure effect for clustered Poisson data: 1) independent Poisson; 2) fixed cluster effects Poisson; 3) conditional likelihood Poisson estimation; 4) Generalized Estimating Equations (GEE); 5) random cluster effects Poisson; and 6) random cluster effects Poisson, with separate between- and within-cluster effects. Biases and standard errors of within- cluster exposure effects are compared across the six statistical methods considering constant or varying exposure ratio (number of exposed to unexposed subjects), constant or varying cluster sizes, different within-cluster exposure effect, different cluster variances, and number of clusters. Simu.. Read More»
  DOI: 10.4172/2155-6180.1000159

  Abstract PDF