Artificial data matrices used by Legendre and Legendre (1998) to exemplify the computation of multivariate Mantel correlograms. S is assumed to represent a similarity matrix computed from assemblage data among 10 sampling sites within a 1-km2 sampling area (Legendre and Legendre 1998: 737). D is the matrix of euclidean distances among the sampling localities (Legendre and Legendre 1998: 718). Zd is another distance matrix, assumed to represent some other multivariate difference among sites (e.g. environmental diferences) that are more accentuated for distances greater than 0.28 km.
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