kknn (version 1.3.1)

contr.dummy: Contrast Matrices

Description

Returns a matrix of contrasts.

Usage

contr.dummy(n, contrasts = TRUE)
contr.ordinal(n, contrasts = TRUE)
contr.metric(n, contrasts = TRUE)

Value

A matrix with n rows and n-1 columns for contr.ordinal, a matrix with n rows and n columns for contr.dummy

and a vector of length n for contr.metric.

Arguments

n

A vector containing levels of a factor, or the number of levels.

contrasts

A logical value indicating whether contrasts should be computed.

Author

Klaus P. Schliep

Details

contr.dummy is standard dummy-coding, contr.metric has the same effect like as.numeric (makes sense of course only for ordered variables). contr.ordinal computes contrasts for ordinal variables.

References

Hechenbichler K. and Schliep K.P. (2004) Weighted k-Nearest-Neighbor Techniques and Ordinal Classification, Discussion Paper 399, SFB 386, Ludwig-Maximilians University Munich (http://www.stat.uni-muenchen.de/sfb386/papers/dsp/paper399.ps)

See Also

contrasts, contr.poly and contr.sdif

Examples

contr.metric(5)
contr.ordinal(5)
contr.dummy(5)