On Wed, Aug 1, 2012 at 2:39 PM, Jason Robinson <[email protected]> wrote: > Hoping someone might be able to steer me in the right direction, not sure > where to look > > I have several different modeling methods to predict patterns of species > occurrences over the same geographic area. I'd like to compare the shape > and position of the predicted areas between maps, in reference to a "true > distribution" map. Since I have irregular polygons instead of raster cells > this gets a little hairy for me to think about coding. > > I thought that epidemiologists might have some experience with this > problem.
Sounds like you could just use the polygon overlay methods in the rgeos package. Should be trivial to overlay your estimates, A, on your truth, B, and get three parts - A on its own, B on its own, and the overlap of A and B. gIntersection and gDifference are probably all you need... Barry _______________________________________________ R-sig-Geo mailing list [email protected] https://stat.ethz.ch/mailman/listinfo/r-sig-geo
