\name{FindA0class} \docType{class} \alias{FindA0-class} \alias{FindA0} \alias{show,FindA0-method} \alias{print,FindA0-method} \alias{plot,FindA0-method} \alias{plot,FindA0,ANY-method} \title{Class FindA0} \description{This is a class representation for the specification of the fudge factor in an EBAM analysis as proposed by Efron et al. (2001). } \section{Objects from the Class}{ Objects can be created using the function \code{find.a0}. } \section{Slots}{ \describe{ \item{\code{mat.z}:}{Object of class \code{"matrix"} containing the expression scores of the genes for each of the possible values for the fudge factor, where each row corresponds to a gene, and each column to one of the values for the fudge factor \eqn{a_0}{a0}.} \item{\code{mat.posterior}:}{Object of class \code{"matrix"} consisting of the posterior probabilities of the genes for each of the possible values for the fudge factor, where each row of \code{mat.posterior} corresponds to a gene, and each column to one of the values for \eqn{a_0}{a0}. The probabilities in \code{mat.posterior} are computed using the monotonically transformed test scores (see the Details section of \code{\link{find.a0}}).} \item{\code{mat.center}:}{Object of class \code{"matrix"} representing the centers of the \code{nrow(mat.center)} intervals used in the logistic regression with repeated observations for estimating \eqn{f/f_0}{f/f0} for each of the \code{ncol(mat.center)} possible values for the fudge factor.} \item{\code{mat.success}:}{Object of class \code{"matrix"} consisting of the numbers of observed test scores in the \code{nrow(mat.success)} intervals used in the logistic regression with repeated observations for each of the \code{ncol(mat.success)} possible values for the fudge factor.} \item{\code{mat.failure}:}{Object of class \code{"matrix"} containing the numbers of permuted test scores in the \code{nrow(mat.failure)} intervals used in the logistic regression with repeated observations for each of the \code{ncol(mat.failure)} possible values for the fudge factor.} \item{\code{z.norm}:}{Object of class \code{"numeric"} comprising the values of the \code{nrow(mat.z)} quantiles of the standard normal distribution (if any \code{mat.z<0}) or an F-distribution (if all \code{mat.z >= 0}).} \item{\code{p0}:}{Object of class \code{"numeric"} specifying the prior probability that a gene is not differentially expressed.} \item{\code{mat.a0}:}{Object of class \code{"data.frame"} comprising the number of differentially expressed genes and the estimated FDR for the possible choices of the fudge factor specified by \code{vec.a0}.} \item{\code{mat.samp}:}{Object of class \code{"matrix"} consisting of the \code{nrow{mat.samp}} permutations of the class labels.} \item{\code{vec.a0}:}{Object of class \code{"numeric"} representing the possible values of the fudge factor \eqn{a_0}{a0}.} \item{\code{suggested}:}{Object of class \code{"numeric"} revealing the suggested choice for the fudge factor, i.e. the value of \code{vec.a0} that leads to the largest number of differentially expressed genes.} \item{\code{delta}:}{Object of class \code{"numeric"} specifying the minimum posterior probability that a gene must have to be called differentially expressed.} \item{\code{df.ratio}:}{Object of class \code{"numeric"} representing the degrees of freedom of the natural cubic spline used in the logistic regression with repeated observations.} \item{\code{msg}:}{Object of class \code{"character"} containing information about, e.g., the type of analysis. \code{msg} is printed when \code{print} is called.} \item{\code{chip}:}{Object of class \code{"character"} naming the microarray used in the analysis. If no information about the chip is available, \code{chip} will be set to \code{""}.} }} \section{Methods}{ \describe{ \item{plot}{\code{signature(object = "FindA0")}: Generates a plot of the (logit-transformed) posterior probabilities of the genes for a specified value of \eqn{\Delta}{Delta} and a set of possible values for the fudge factor. For details, see \code{help.finda0(plot)}. For the arguments, see \code{args.finda0(plot)}.} \item{print}{\code{signature(object = "FindA0")}: Prints the number of differentially expressed genes and the estimated FDR for each of the possible values of the fudge factor specified by \code{vec.a0}. For details, see \code{help.finda0(print)}. For arguments, see \code{args.finda0(print)}.} \item{show}{\code{signature(object = "FindA0")}: Shows the output of an analysis with \code{find.a0}.} }} \references{ Efron, B., Tibshirani, R., Storey, J.D. and Tusher, V. (2001). Empirical Bayes Analysis of a Microarray Experiment, \emph{JASA}, 96, 1151-1160. Schwender, H., Krause, A. and Ickstadt, K. (2003). Comparison of the Empirical Bayes and the Significance Analysis of Microarrays. \emph{Technical Report}, SFB 475, University of Dortmund, Germany. } \author{Holger Schwender, \email{holger.schw@gmx.de}} \seealso{\code{\link{find.a0}}, \code{\link{ebam}}, \code{\link{EBAM-class}}} \keyword{classes}