simulation {blender} | R Documentation |
Simulate reduced richness landscapes
Description
reduce
randomly selects species for inclusion in a reduced-richness
landscape based on the original. shuffle
randomizes species locations
among sites.
Usage
blender.reduce(landscape, richness)
blender.shuffle(landscape)
Arguments
landscape |
A binary presence-absence |
richness |
An integer number of species to include in a reduced landscape |
Details
Species are sampled by reduce
without replacement. Species
are randomized by shuffle
in order to preserve their occupancy
rates (row sums) but not local richness (column sums).
Value
A data.frame
based on landscape
Author(s)
David J. Harris <DavHarris@UCDavis.edu>
References
These functions were used in the simulations in Harris, D. J., K. G. Smith, and P. J. Hanly. 2011. "Occupancy is nine-tenths of the law: Occupancy rates determine the homogenizing and differentiating effects of exotic species." The American Naturalist.