RankingWilcoxon {GeneSelector} | R Documentation |
The Wilcoxon statistic is rank-based and 'distribution free'.
It is equivalent to the Mann-Whitney statistic and also related to the 'Area under
the curve' (AUC) in the two sample case. The implementation
is efficient, but still far slower than that of the t-statistic.
For S4
method information, see RankingWilcoxon-methods.
RankingWilcoxon(x, y, type = c("unpaired", "paired", "onesample"), pvalues = FALSE, gene.names = NULL, ...)
x |
A matrix of gene expression values with rows
corresponding to genes and columns corresponding to observations or alternatively an object of class ExpressionSet .If type = paired , the first half of the columns corresponds to
the first measurements and the second half to the second ones.
For instance, if there are 10 observations, each measured twice,
stored in an expression matrix expr ,
then expr[,1] is paired with expr[,11] , expr[,2]
with expr[,12] , and so on. |
y |
If x is a matrix, then y may be
a numeric vector or a factor with at most two levels.If x is an ExpressionSet , then y
is a character specifying the phenotype variable in
the output from pData .If type = paired , take care that the coding is
analogously to the requirement concerning x |
type |
|
pvalues |
Should p-values be computed ? Default is FALSE . |
gene.names |
An optional vector of gene names. |
... |
Currently unused argument. |
An object of class GeneRanking.
Note that although the Wilcoxon Rank Sum test is distribution-free, it is not without assumptions.
Martin Slawski martin.slawski@campus.lmu.de
Anne-Laure Boulesteix http://www.slcmsr.net/boulesteix
GetRepeatRanking, RankingTstat, RankingFC, RankingWelchT, RankingBaldiLong, RankingFoxDimmic, RankingLimma, RankingEbam, RankingWilcEbam, RankingSam, RankingBstat, RankingShrinkageT, RankingSoftthresholdT, RankingPermutation, RankingGap, wilcox.test
## Load toy gene expression data data(toydata) ### class labels yy <- toydata[1,] ### gene expression xx <- toydata[-1,] ### run RankingWilcoxon wilcox <- RankingWilcoxon(xx, yy, type="unpaired")