AlgDesign (version 1.0-10)

gen.mixture: Generate mixture

Description

Creates a candidate list of mixture variables.

Usage

gen.mixture(levels,vars)

Arguments

levels

An integer greater than 1. The number of levels of the mixture variables.

vars

Either the number of variables, or a character vector of variable names.

Details

Similar in function to gen.factorial(), but for mixture variables such that the rows sum to unity. For levels=2, the identity matrix is produced, so that each variable is either 0 or 1. For levels=3, rows are added to the identity containing two variables at 1/2 and the others at 0. etc.

In general, a mixture model of degree d will have the same number of terms as the candidate list generated by gen.mixture for levels=d+1, and this will be optimal.