\name{postprob} \alias{postprob} \alias{postprob,ebarraysEMfit,ExpressionSet-method} \alias{postprob,ebarraysEMfit,matrix-method} \alias{show,ebarraysPostProb-method} \alias{ebarraysPostProb-class} \title{Calculates posterior probabilities for expression patterns} \description{ Takes the output from emfit and calculates the posterior probability of each of the hypotheses, for each gene. } \usage{ postprob(fit, data, ...) } \arguments{ \item{fit}{ output from \code{\link{emfit}}} \item{data}{ a numeric matrix or an object of class ``ExpressionSet'' containing the data, typically the same one used in the \code{emfit} fit supplied below. } \item{\dots}{ other arguments, ignored} } \value{ An object of class ``ebarraysPostProb''. Slot \code{joint} is an three dimensional array of probabilities. Each element gives the posterior probability that a gene belongs to certain cluster and have certain pattern. \code{cluster} is a matrix of probabilities with number of rows given by the number of genes in \code{data} and as many columns as the number of clusters for the fit. \code{pattern} is a matrix of probabilities with number of rows given by the number of genes in \code{data} and as many columns as the number of patterns for the fit. It additionally contains a slot `hypotheses' containing these hypotheses. } \author{Ming Yuan, Ping Wang, Deepayan Sarkar, Michael Newton, and Christina Kendziorski} \references{ Newton, M.A., Kendziorski, C.M., Richmond, C.S., Blattner, F.R. (2001). On differential variability of expression ratios: Improving statistical inference about gene expression changes from microarray data. Journal of Computational Biology 8:37-52. Kendziorski, C.M., Newton, M.A., Lan, H., Gould, M.N. (2003). On parametric empirical Bayes methods for comparing multiple groups using replicated gene expression profiles. Statistics in Medicine 22:3899-3914. Newton, M.A. and Kendziorski, C.M. Parametric Empirical Bayes Methods for Microarrays in The analysis of gene expression data: methods and software. Eds. G. Parmigiani, E.S. Garrett, R. Irizarry and S.L. Zeger, New York: Springer Verlag, 2003. Newton, M.A., Noueiry, A., Sarkar, D., and Ahlquist, P. (2004). Detecting differential gene expression with a semiparametric hierarchical mixture model. Biostatistics 5: 155-176. Yuan, M. and Kendziorski, C. (2006). A unified approach for simultaneous gene clustering and differential expression identification. Biometrics 62(4): 1089-1098. } \seealso{ \code{\link{emfit}} } \examples{ data(sample.ExpressionSet) ## from Biobase eset <- exprs(sample.ExpressionSet) patterns <- ebPatterns(c("1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1", "1 1 1 1 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 2 2 2 2 2")) gg.fit <- emfit(data = eset, family = "GG", hypotheses = patterns, verbose = TRUE) prob <- postprob(gg.fit,eset) } \keyword{models}