zscore {limma} | R Documentation

## Z-score Equivalents

### Description

Compute z-score equivalents of for gamma or t-distribution random deviates.

### Usage

    zscoreGamma(q, shape, rate = 1, scale = 1/rate)
    zscoreT(x, df)
    tZscore(x, df)

### Arguments

`q, x` | numeric matrix for vector giving deviates of a random variaable
`shape` | gamma shape parameter (>0)
`rate` | gamma rate parameter (>0)
`scale` | gamma scale parameter (>0)
`df` | degrees of freedom (>0 for `zscore` or >=1 for `tZscore`)

### Details

These functions compute the standard normal deviates which have the same quantiles as the given values in the specified distribution. For example, if `z <- zscoreT(x,df=df)` then `pnorm(z)` equals `pt(x,df=df)`. `tZscore` is the inverse of `zscoreT`.

Care is taken to do the computations accurately in both tails of the distributions.

### Value

Numeric vector giving equivalent deviates from a standard normal distribution (`zscoreGamma` and `zscoreT`) or deviates from a t-distribution (`tZscore`).

### Author(s)

Gordon Smyth

### See Also

`qnorm`, `pgamma`, `pt`

### Examples

    zscoreGamma(1, shape=1, scale=1)
    zscoreT(2, df=3)
    tZscore(2, df=3)

[Package limma version 2.2.0 Index]