EM: EM

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

View source: R/interfaces.R

Description

estimates a GMM on data using EM algorithm.

Usage

1
2
EM(data, ncomp, model=c("general", "diagonal", "spherical"), class=FALSE, 
	thres = 0.1, maxit = NULL, rbic=FALSE, debug=FALSE)

Arguments

data

matrix of row-elements.

ncomp

maximal number of components in the GMM. In case of degeneracies, the final model size may be less than ncomp.

model

Hypothesis on the modfel to estimate: "general", "diagonal" or "spherical" covariance matrices.

class

If TRUE, hard allocate elements in the E step (see CEM variant in Biernacki et al.). If FALSE, compute soft responsibilities as in usual EM algorithm.

thres

threshold for lower bound variations between 2 iterations. Convergence is decided if this variation is below thres.

maxit

if NULL, the stopping criterion is related to thres. If not NULL, maxit iterations are performed.

rbic

if FALSE, output BIC criterion associated to the obtained GMM. If TRUE, use a variant that accounts for the dimensionality of the model.

debug

if TRUE, display debug markers.

Value

estimated GMM with at most ncomp components, with labels containing associated labels for data in addition.

labels

Cluster labels taking values in 1..k

w

Numeric vector of cluster weights

mean

List of mean vectors

cov

List of covariance matrices

likelihood

Likelihood value of the model

bic

BIC criterion of the model

Author(s)

Pierrick Bruneau

References

Bishop, C. M. (2006) _Pattern Recognition and Machine Learning_, Chapter 9, Springer. Biernacki, C. et al. _Model-based cluster and discriminant analysis with the MIXMOD software_, Computational Statistics and Data Analysis 51.2 (2006): 587-600.

See Also

newGmm varbayes

Examples

1
temp <- EM(irisdata, 4)

VBmix documentation built on May 30, 2017, 2:34 a.m.

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