R: Residual variance of a model

varmlm {compositions} | R Documentation

## Residual variance of a model

### Description

Computes the unbiased estimate for the variance of the residuals of a model.

### Usage

    ## S3 method for class 'mlm'
    var(x,...)
    ## S3 method for class 'lm'
    var(x,...)

### Arguments

`x` | a linear model object
`...` | Unused, for generic purposes only.

### Details

The difference of this command to `var(resid(X))` is that this command correctly adjusts for the degrees of freedom of the model.

### Value

`var.lm` | returns a scalar giving the estimated variance of the residuals
`var.mlm` | returns a the estimated variance covariance matrix of the residuals

### Author(s)

K.Gerald v.d. Boogaart http://www.stat.boogaart.de, Raimon Tolosana-Delgado

### See Also

`vcov`

### Examples

    data(Orange)
    var(lm(circumference~age,data=Orange))
    var(lm(cbind(circumference,age)~age,data=Orange))

[Package compositions version 1.40-3 Index]