ZORRO: A Randomization Test for Spatial Pattern
Computers & Geosciences
ZORRO, a FORTRAN-77 program, performs a conditional randomization text on the hypothesis that two or more types of individuals are distributed in space by a random process. The space may be one-, two-, or three-dimensional, and "type" may be any label signifying for example, events, classes, or species. The test is conditional on actual locations where individuals are observed, rather than with respect to space itself. The test statistic is based on the nearest-neighbor distance.
H.C. Romesburg. 1989. ZORRO: A Randomization Test for Spatial Pattern. Computers and Geosciences, 15(6):1011-1017.