Hello, I've used mantel tests a fair bit for standard genetic/geographic/landscape analyses. I realize it involves permutations of rows and columns in the matrix to obtain correlation coefficients. However, for a certain question, I am interested in populations that are nearest neighbours to each other, and identifying factors that affect genetic distance between them. So because of autocorrelation problems, I can't use standard regression or correlation, because some populations appear several times depending upon their spatial arrangement. In essence I am cherry picking a typical matrix, but only for populations that are closest. Is there code or a test that can handle this problem? It seems very similar to a mantel, but only for a subset of possible pairs, not all possible pairwise comparisons as a mantel would handle. What about a bootstrapping algorithm than handles populations as the sample unit instead of individual data points? I bet mixed models could handle this problem somehow, but I'd like to stick to the theme of a mantel test. The data look like this pop1 pop2 genetic_distance(dependent) (independent1) popa popb data data popb popd data data popc pope data data popf popg data data popg poph data data So for example, popb appears twice, as does popg. Clearly each row is not independent. Thanks for any insight Rob. -- View this message in context: http://r.789695.n4.nabble.com/Mantel-like-analysis-tp3564296p3564296.html Sent from the R help mailing list archive at Nabble.com.