R: Find the Response Vector and Design Matrix for a W&R Model...

wr {rmutil} | R Documentation

## Find the Response Vector and Design Matrix for a W\&R Model Formula

### Description

`wr` gives the response vector and design matrix for a formula in Wilkinson and Rogers notation.

### Usage

    wr(formula, data=NULL, expand=TRUE)

### Arguments

`formula` | A model formula.
`data` | A data object or environment.
`expand` | If FALSE, the covariates are read from the `tccov` object without expanding to the length of the response variable.

### Value

`wr` returns a list containing the response vector (`z$response`), if included in the formula, and the design matrix (`z$design`) from the data object or environment supplied or from the global environment for the formula supplied.

### Author(s)

J.K. Lindsey

### Examples

    y <- rnorm(20)
    x <- gl(4,5)
    z <- rpois(20,2)
    wr(y~x+z)

[Package rmutil version 1.1.3 Index]