contr.dummy: Contrast Matrices
In kknn: Weighted k-Nearest Neighbors

Description Usage Arguments Details Value Author(s) References See Also Examples

Returns a matrix of contrasts.

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

`n`	A vector containing levels of a factor, or the number of levels.
`contrasts`	A logical value indicating whether contrasts should be computed.

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.

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.

Klaus P. Schliep klaus.schliep@gmail.com

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)

contrasts, contr.poly and contr.sdif

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

  [,1]
1   -2
2   -1
3    0
4    1
5    2
  [,1] [,2] [,3] [,4]
1  0.5  0.5  0.5  0.5
2 -0.5  0.5  0.5  0.5
3 -0.5 -0.5  0.5  0.5
4 -0.5 -0.5 -0.5  0.5
5 -0.5 -0.5 -0.5 -0.5
  1 2 3 4 5
1 1 0 0 0 0
2 0 1 0 0 0
3 0 0 1 0 0
4 0 0 0 1 0
5 0 0 0 0 1