sigma {robustbase} | R Documentation

## Extract 'Sigma' - Standard Deviation of Errors for Robust Models

### Description

Extract the estimated standard deviation of the errors, the “residual standard deviation” (misnomed also “residual standard error”) from a fitted model.

### Usage

    ## S3 method for class 'lmrob'
    sigma(object, ...)

### Arguments

`object` | a fitted model.
`...` | additional, optional arguments. (None are used in our methods)

### Details

For R `<= 3.2.x`, we provide an (S3) generic function (as e.g., package lme4) and methods for `lmrob`, `nlrob`, and `nls`.

From R `>= 3.3.0`, we provide methods for our `lmrob` and `nlrob` models.

### Value

the residual standard error as a scalar

### Examples

          m.cl <-   lm (Y ~ ., data=coleman)
    if(getRversion() >= "3.3.0")  sigma(m.cl)  else  summary(m.cl)$sigma
    sigma( m1  <- lmrob(Y ~ ., data=coleman) )
    sigma( m2  <- lmrob(Y ~ ., data=coleman, setting = "KS2014") )

[Package robustbase version 0.93-4 Index]