randomLinComb: Compute a random linear combination of the columns of a...

In alr3: Data to Accompany Applied Linear Regression 3rd Edition

Description

Computes Xa where X is an n by p matrix, and a is a random vector of length p.

Usage

randomLinComb(X, seed = NULL)

## S3 method for class 'lm'
 randomLinComb(X, seed=NULL)

Arguments

X	An n by p matrix or data frame. For the lm method, X is a linear regression model, and randomLinComb is applied to model.matrix(X)
seed	If not NULL, use this to initialize the random number generator

Details

The matrix X is first scaled and centered. a is computed to have random uniform components on (-1,1).

Value

A vector of length n.

Author(s)

Sanford Weisberg, [e-mail]

See Also

pure.error.anova

Examples

randomLinComb(matrix(rnorm(9),ncol=3))

alr3 documentation built on May 2, 2019, 5:39 a.m.