R: Bootstrap Flexclust Algorithms

bootFlexclust {flexclust} | R Documentation

## Bootstrap Flexclust Algorithms

### Description

Runs clustering algorithms repeatedly for different numbers of clusters on bootstrap replica of the original data and returns corresponding cluster assignments, centroids and (adjusted) Rand indices comparing pairs of partitions.

### Usage

    bootFlexclust(x, k, nboot=100, correct=TRUE, seed=NULL,
                  multicore=TRUE, verbose=FALSE, ...)

    ## S4 method for signature 'bootFlexclust'
    summary(object)
    ## S4 method for signature 'bootFlexclust,missing'
    plot(x, y, ...)
    ## S4 method for signature 'bootFlexclust'
    boxplot(x, ...)
    ## S4 method for signature 'bootFlexclust'
    densityplot(x, data, ...)

### Arguments

`x, k, ...` | Passed to `stepFlexclust`.
`nboot` | Number of bootstrap pairs of partitions.
`correct` | Logical, correct the Rand index for agreement by chance also called adjusted Rand index)?
`seed` | If not `NULL`, a call to `set.seed()` is made before any clustering is done.
`multicore` | If `TRUE`, use package parallel for parallel processing. In addition, it may be a workstation cluster object as returned by `makeCluster`, see examples below.
`verbose` | If `TRUE`, show progress information during computations. Will not work with `multicore=TRUE`.
`y, data` | Not used.
`object` | An object of class `"bootFlexclust"`.

### Details

Availability of multicore is checked when flexclust is loaded. This information is stored and can be obtained using `getOption("flexclust")$have_multicore`. Set to `FALSE` for debugging and more sensible error messages in case something goes wrong.

### Author(s)

Friedrich Leisch

### See Also

`stepFlexclust`

### Examples

    ## Not run:

    ## data uniform on unit square
    x <- matrix(runif(400), ncol=2)

    cl <- FALSE

    ## to run bootstrap replications on a workstation cluster do the following:
    library("parallel")
    cl <- makeCluster(2, type = "PSOCK")
    clusterCall(cl, function() require("flexclust"))

    ## 50 bootstrap replicates for speed in example,
    ## use more for real applications
    bcl <- bootFlexclust(x, k=2:7, nboot=50, FUN=cclust, multicore=cl)

    bcl
    summary(bcl)

    ## splitting the square into four quadrants should be the most stable
    ## solution (increase nboot if not)
    plot(bcl)
    densityplot(bcl, from=0)

    ## End(Not run)

[Package flexclust version 1.4-1 Index]