R: Multiple T Tests by Matrix Multiplication

matrixT {oompaBase} | R Documentation

## Multiple T Tests by Matrix Multiplication

### Description

Utility functions for computing vectors of row-by-row means, variances, and t-statistics.

### Usage

    matrixMean(x,na.rm=FALSE)
    matrixVar(x, xmean, na.rm=FALSE)
    matrixT(m, v, na.rm=FALSE)
    matrixUnequalT(m, v)
    matrixPairedT(m, v, pf)

### Arguments

`x` | a matrix
`xmean` | a numeric vector or single-column matrix
`m` | a matrix
`na.rm` | a logical value indicating whether means, variances, and t-statistics should be computed after omitting NA values from individual rows of the data matrix.
`v` | a logical vector of length equal to the number of columns of `m`
`pf` | a numerical vector of length equal to the number of columns of `m`, indicating which samples should be paired

### Value

`matrixMean` returns a single-column matrix containing the row-by-row means of `x`.

`matrixVar` returns a single-column matrix containing the row-by-row means of `x`, assuming that `xmean` contains the corresponding mean values.

`matrixT` returns a single-column matrix of t-statistics from a two-sample t-test comparing the columns for which `v` is true to those for which `v` is false.

`matrixPairedT` returns a single-column matrix of t-statistics from a paired t-test.

`matrixUnequalT` returns a list with two components: `tt` is a single-column matrix of t-statistics from a two-sample unequal variance t-test comparing the columns for which `v` is true to those for which `v` is false, and `df` is a single-column matrix of the degrees of freedom associated with each row..

### Author(s)

Kevin R. Coombes <krc@silicovore.com>

### Examples

    ng <- 1000
    ns <- 50
    dat <- matrix(rnorm(ng*ns), ncol=ns)
    clas <- factor(rep(c('Good', 'Bad'), each=25))
    myMean <- matrixMean(dat)
    myVar  <- matrixVar(dat, myMean)
    plot(myMean, myVar)

    myT <- matrixT(dat, clas)
    hist(myT)

    rm(ng, ns, dat, myMean, myVar, myT)

[Package oompaBase version 3.2.6 Index]