R: Mean t-Statistic Between Two Groups of Growth Curves

meanT {statmod} | R Documentation

## Mean t-Statistic Between Two Groups of Growth Curves

### Description

The mean-t statistic of the distance between two groups of growth curves.

### Usage

    meanT(y1, y2)

### Arguments

`y1` | matrix of response values for the first group, with a row for each individual and a column for each time. Missing values are allowed.
`y2` | matrix of response values for the second group. Must have the same number of columns as `y1`. Missing values are allowed.

### Details

This function computes the pooled two-sample t-statistic between the response values at each time, and returns the mean of these values weighted by the degrees of freedom. This function is used by `compareGrowthCurves`.

### Value

numeric vector of length one containing the mean t-statistic.

### Author(s)

Gordon Smyth

### See Also

`compareGrowthCurves`, `compareTwoGrowthCurves`

### Examples

    y1 <- matrix(rnorm(4*3),4,3)
    y2 <- matrix(rnorm(4*3),4,3)
    meanT(y1,y2)

    data(PlantGrowth)
    compareGrowthCurves(PlantGrowth$group,as.matrix(PlantGrowth$weight))
    # Can make p-values more accurate by nsim=10000

[Package statmod version 1.4.36 Index]