## Usage

sim6(speciesData)

## Arguments

- speciesData
- binary presence-absence matrix
(rows = species, columns = sites).

## Value

Returns a binary presence-absence matrix with the same
dimensions and fill as the input matrix.

## Description

Randomizes a binary matrix speciesData by reshuffling all
elements. Rows are equiprobable, and columns are proportional to column sums.
Makes a call to the vector_sample function.

## Details

This algorithm assumes that species are equiprobable, but that
differences in suitability among sites are proportional to observed species
richness (=colsums).

## Note

This algorithm assumes that species are equiprobable, and that
differences among sites are proportional to observed species richness
(=colsums). sim6 has a high frequency of Type I errors with random matrices,
so it is not recommended for co-occurrence analysis.

## References

Gotelli, N.J. 2000. Null model analysis of species co-occurrence
patterns. Ecology 81: 2606-2621.

## Examples

randomMatrix <- sim6(speciesData = matrix(rbinom(40,1,0.5),nrow=8))