Randomizes a binary matrix speciesData by reshuffling all of its elements equiprobably.
binary presence-absence matrix (rows = species, columns = sites).
This algorithm assumes species and sites are equiprobable. It preserves the total matrix fill, but places no other constraints on row or column totals.
Returns a binary presence-absence matrix with the same dimensions and percent fill as the input matrix.
This is the simplest of all randomization algorithms for a presence- absence matrix. However, it assumes that both species and sites are equiprobable, and has poor Type I error frequencies when tested with purely random matrices. If the input matrix is sparse, it will often generate null matrices with empty rows or columns. Not recommended for co-occurrence analysis.
Gotelli, N.J. 2000. Null model analysis of species co-occurrence patterns. Ecology 81: 2606-2621.
Add the following code to your website.
For more information on customizing the embed code, read Embedding Snippets.