\name{iterativeBMA-package} \alias{iterativeBMA-package} \alias{iterativeBMA} \docType{package} \title{ The Iterative Bayesian Model Averaging (BMA) algorithm } \description{ The iterative Bayesian Model Averaging (BMA) algorithm is a variable selection and classification algorithm with an application of classifying 2-class microarray samples, as described in Yeung, Bumgarner and Raftery (Bioinformatics 2005, 21: 2394-2402). } \details{ \tabular{ll}{ Package: \tab iterativeBMA\cr Type: \tab Package\cr Version: \tab 0.1.0\cr Date: \tab 2005-12-30\cr License: \tab GPL version 2 or higher\cr } The function \code{iterateBMAglm.train} selects relevant variables by iteratively applying the \code{bic.glm} function from the \code{BMA} package. The data is assumed to consist of two classes. The function \code{iterateBMAglm.train.predict} combines the training and prediction phases, and returns the predicted posterior probabilities that each test sample belongs to class 1. The function \code{iterateBMAglm.train.predict.test} combines the training, prediction and test phases, and returns a list consisting of the numbers of selected genes and models using the training data, the number of classification errors and the Brier Score on the test set. } \author{ Ka Yee Yeung, University of Washington, Seattle, WA, with contributions from Adrian Raftery and Ian Painter Maintainer: Ka Yee Yeung } \references{ Yeung, K.Y., Bumgarner, R.E. and Raftery, A.E. (2005) Bayesian Model Averaging: Development of an improved multi-class, gene selection and classification tool for microarray data. Bioinformatics 21: 2394-2402. } \keyword{multivariate} \keyword{classif} \seealso{\code{\link{iterateBMAglm.train.predict}}, \code{\link{iterateBMAglm.train.predict.test}}, \code{\link{bma.predict}}, \code{\link{brier.score}} } \examples{ library (Biobase) library (BMA) library (iterativeBMA) data(trainData) data(trainClass) ## training phase: select relevant genes ret.bic.glm <- iterateBMAglm.train (train.expr.set=trainData, trainClass, p=100) ## get the selected genes with probne0 > 0 ret.gene.names <- ret.bic.glm$namesx[ret.bic.glm$probne0 > 0] data (testData) ## get the subset of test data with the genes from the last iteration of bic.glm curr.test.dat <- t(exprs(testData)[ret.gene.names,]) ## to compute the predicted probabilities for the test samples y.pred.test <- apply (curr.test.dat, 1, bma.predict, postprobArr=ret.bic.glm$postprob, mleArr=ret.bic.glm$mle) ## compute the Brier Score if the class labels of the test samples are known data (testClass) brier.score (y.pred.test, testClass) }