HEM

Heterogeneous Error Model for Analysis of Microarray Data

HEM is a Bayesian heterogeneous error modeling method for analysis of microarray data, developed by HyungJun Cho, PhD, and Jae K. Lee, PhD, at the University of Virginia School of Medicine.  Some features are

  • Simultaneous estimation of parameters by Markov Chain Monte Carlo (MCMC)
  • Decomposition of error variability into two error components with experimental (or technical) and biological replicates
  • Heterogeneous error variances for all genes under multiple conditions
  • Parametric or nonparametric Empirical Bayes (EB) prior specification of variances
  • Resampling-based False Discovery Rate (FDR) evaluation for thresholding
  • High statistical power with a small number of replicates

 

Documentation:

  • Cho, H. and Lee, J.K. (2004). Vignette for HEM package in R, (PDF)
  • Cho, H. and Lee, J.K. (2004). Bayesian Hierarchical Error Model for Analysis of Gene Expression Data, Bioinformatics, 20: 2016-2025(PDF)
  • Cho, H  and Lee, J.K. (2005). Heterogeneous Error Model for Analysis of Microarray Data Using Nonparametric Empirical Bayes Approach, submitted for publication
  • Cho, H  and Lee, J.K. (2005). Empirical Bayes Analysis of Microarray Data Without Replication, submitted for publication

 

Software:

 

The libraries may be freely distributed but not sold for profit. Please contact HyungJun Cho, PhD (e-mail: hcho@virginia.edu) at Division of Biostatistics and Epidemiology, Department of Public Health Sciences, University of Virginia School of Medicine.