Mixture model selection via BIC {Compositional} R Documentation

## Mixture model selection via BIC

### Description

Mixture model selection via BIC.

### Usage

```bic.mixcompnorm(x, G, type = "alr", veo = FALSE, graph = TRUE)
```

### Arguments

 `x` A matrix with compositional data. `G` A numeric vector with the number of components, clusters, to be considered. `type` The type of trasformation to be used, either the additive log-ratio ("alr"), the isometric log-ratio ("ilr") or the pivot coordinate ("pivot") transformation. `veo` Stands for "Variables exceed observations". If TRUE then if the number variablesin the model exceeds the number of observations, but the model is still fitted. `graph` A boolean variable, TRUE or FALSE specifying whether a graph should be drawn or not.

### Details

The alr or the ilr-transformation is applied to the compositional data first and then mixtures of multivariate Gaussian distributions are fitted. BIC is used to decide on the optimal model and number of components.

### Value

A plot with the BIC of the best model for each number of components versus the number of components. A list including:

 `mod` A message informing the user about the best model. `BIC` The BIC values for every possible model and number of components.

### Author(s)

Michail Tsagris

R implementation and documentation: Michail Tsagris mtsagris@uoc.gr.

### References

Ryan P. Browne, Aisha ElSherbiny and Paul D. McNicholas (2018). mixture: Mixture Models for Clustering and Classification. R package version 1.5.

Ryan P. Browne and Paul D. McNicholas (2014). Estimating Common Principal Components in High Dimensions. Advances in Data Analysis and Classification, 8(2), 217-226.

Aitchison J. (1986). The statistical analysis of compositional data. Chapman & Hall.

```mix.compnorm, mixnorm.contour, rmixcomp, bic.alfamixnorm ```

### Examples

```## Not run:
x <- as.matrix( iris[, 1:4] )
x <- x/ rowSums(x)
bic.mixcompnorm(x, 1:3, type = "alr", graph = FALSE)
bic.mixcompnorm(x, 1:3, type = "ilr", graph = FALSE)

## End(Not run)
```

[Package Compositional version 5.2 Index]