R: Ridgeline Pi-function

piridge {fpc} | R Documentation

## Ridgeline Pi-function

### Description

The Pi-function is given in (6) in Ray and Lindsay, 2005. Equating it to the mixture proportion yields locations of two-component Gaussian mixture density extrema.

### Usage

    piridge(alpha, mu1, mu2, Sigma1, Sigma2, showplot=FALSE)

### Arguments

`alpha` | sequence of values between 0 and 1 for which the Pi-function is computed.
`mu1` | mean vector of component 1.
`mu2` | mean vector of component 2.
`Sigma1` | covariance matrix of component 1.
`Sigma2` | covariance matrix of component 2.
`showplot` | logical. If `TRUE`, the Pi-function is plotted against `alpha`.

### Value

Vector of values of the Pi-function for values of `alpha`.

### Author(s)

Christian Hennig c.hennig@ucl.ac.uk http://www.homepages.ucl.ac.uk/~ucakche/

### References

Ray, S. and Lindsay, B. G. (2005) The Topography of Multivariate Normal Mixtures, Annals of Statistics, 33, 2042-2065.

### Examples

      q <- piridge(seq(0,1,0.1),c(1,1),c(2,5),diag(2),diag(2))

[Package fpc version 2.1-10 Index]