Hi - is the 2-D Kolmogorov-Smirnov test of Fasano & Francheschini (1987) implemented in any of the R-packages at present? The algorithm and code exist in the Numerical Recipes series (e.g. Press et al. 1992) but I thought I should check before playing with .C() and dyn.load() for the first time... Thanks in advance, Rich Fasano G and Franceschini A 1987 A multi-dimensional version of the Kolmorogov-Smirnov test Mon. Not. R. Astron. Soc. 225 155-70 Press W H, Teukolsky S A, Vettering W T and Flannery B P 1992 Numerical Recipes in FORTRAN: The Art of Scientific Computing (Cambridge: Cambridge University Press) p 640ff -------------------- Rich Grenyer, Ph.D. Biology Department - University of Virginia Gilmer Hall Charlottesville, Virginia VA 22904 United States of America tel: (+1) 434 982 5629 fax: (+1) 434 982 5626 http://faculty.virginia.edu/gittleman/rich