Supplement 2. R code for simulating binary assemblage data that exhibit directional change in species composition.
R code written to simulate binary species assemblage data that displays an increasing or decreasing directional temporal trend within multiple sites for use in a Monte Carlo power analysis. To simulate a community displaying increasing directional trend use the function SimPopALL, an example is included for illustration. To simulate a community consistent with decreasing directional trend use the function SimPopALL.nonlin, an example is provided. The required inputs to the functions are described within the file. The output from both functions is a list with component called Y.ALL for the simulated data matrix with 1st column the site id, 2nd column year id, and remaining columns for species. This function can be used to simulate data under a specified alternative hypothesis within an iterative procedure as described in the paper.