R: Bootstrap a flexmix Object

boot {flexmix} | R Documentation

## Bootstrap a flexmix Object

### Description

Given a `flexmix` object perform parametric or empirical bootstrap.

### Usage

    boot(object, ...)
    ## S4 method for signature 'flexmix'
    boot(object, R, sim = c("ordinary", "empirical", "parametric"),
        initialize_solution = FALSE, keep_weights = FALSE,
        keep_groups = TRUE, verbose = 0, control,
        k, model = FALSE, ...)
    LR_test(object, ...)
    ## S4 method for signature 'flexmix'
    LR_test(object, R, alternative = c("greater", "less"), control, ...)

### Arguments

`object` | A fitted finite mixture model of class `flexmix`.
`R` | The number of bootstrap replicates.
`sim` | A character string indicating the type of simulation required. Possible values are `"ordinary"` (the default), `"parametric"`, or `"empirical"`.
`initialize_solution` | A logical. If `TRUE` the EM algorithm is initialized in the given solution.
`keep_weights` | A logical. If `TRUE` the weights are kept.
`keep_groups` | A logical. If `TRUE` the groups are kept.
`verbose` | If a positive integer, then progress information is reported every `verbose` iterations. If 0, no output is generated during the bootstrap replications.
`control` | Object of class `FLXcontrol` or a named list. If missing the control of the fitted `object` is taken.
`k` | Vector of integers specifying for which number of components finite mixtures are fitted to the bootstrap samples. If missing the number of components of the fitted `object` are taken.
`alternative` | A character string specifying the alternative hypothesis, must be either `"greater"` (default) or `"less"` indicating if the alternative hypothesis is that the mixture has one more component or one less.
`model` | A logical. If `TRUE` the model and the weights slot for each sample are stored and returned.
`...` | Further arguments to be passed to or from methods.

### Value

`boot` returns an object of class `FLXboot` which contains the fitted parameters, the fitted priors, the log likelihoods, the number of components of the fitted mixtures and the information if the EM algorithm has converged.

`LR_test` returns an object of class `htest` containing the number of valid bootstrap replicates, the p-value, the - twice log likelihood ratio test statistics for the original data and the bootstrap replicates.

### Author(s)

Bettina Gruen

### Examples

    data("NPreg", package = "flexmix")
    fitted <- initFlexmix(yn ~ x + I(x^2) | id2, data = NPreg, k = 2)
    ## Not run:
    lrtest <- LR_test(fitted, alternative = "greater", R = 20,
                      verbose = 1)

    ## End(Not run)

[Package flexmix version 2.3-14 Index]