mix.vmf: Mixtures of Von Mises-Fisher distributions
In Directional: Directional Statistics

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

View source: R/mix.vmf.R

It performs model based clustering for circualr, spherical and hyperspherical data assuming von Mises-Fisher distributions.

1	mix.vmf(x, g)

`x`	A matrix with the data expressed as unit vectors.
`g`	The number of groups to fit. It must be greater than or equal to 2.

The initial step of the algorithm is not based on a spherical k-means, but on s imple k-means. The results are comparable to the package movMF.

A list including:

`param`	A matrix with the mean direction, the concetrations parameter and mixing probability of each group.
`loglik`	The value of the maximised log-likelihood.
`pred`	The predicted group of each observation.
`runtime`	The run time of the algorithm. A numeric vector. The first element is the user time, the second element is the system time and the third element is the elapsed time.

Michail Tsagris

R implementation and documentation: Michail Tsagris <mtsagris@yahoo.gr> and Giorgos Athineou <athineou@csd.uoc.gr>

Kurt Hornik and Bettina Grun (2014). movMF: An R Package for Fitting Mixtures of von Mises-Fisher Distributions http://cran.r-project.org/web/packages/movMF/vignettes/movMF.pdf

rmixvmf, bic.mixvmf, mixvmf.contour

k <- runif(4, 4, 20)
prob <- c(0.2, 0.4, 0.3, 0.1)
mu <- matrix(rnorm(16), ncol = 4)
mu <- mu / sqrt( rowSums(mu^2) )
x <- rmixvmf(200, prob, mu, k)$x
mix.vmf(x, 3)
mix.vmf(x, 4)
mix.vmf(x, 5)