dummy.code: Convert a factor to a matrix of dummy codes
Description
Converts a factor (categorical) variable to a matrix of dummy codes
using a 1 of C-1 binary coding scheme.
Usage
dummy.code(x)
Arguments
x
a factor variable.
Value
a matrix with the number of rows equal to the number of cases in x
and the number of columns equal to one minus the number of factors in
x. The last factor serves as the reference group.