is that if the null hypothesis of there being no relation between the two matrices is true, then permuting the rows and columns of the matrix should be equally likely to produce a larger or a smaller coefficient. In addition to overcoming the problems arising from the statistical dependence of elements within each of the two matrices, use of the permutation test means that no reliance is being placed on assumptions about the statistical distributions of elements in the matrices. Many statistical packages include routines for carrying out the Mantel test. Criticism The various papers introducing the Mantel test (and its extension, the partial Mantel test) lack a clear statistical framework specifying fully the null and alternative hypotheses. This may convey the wrong idea that these tests are universal. For example, the Mantel and partial Mantel tests can be flawed in the presence of spatial auto-correlation and return erroneously low p-values. See, e.g., Guillot and Rousset (2013). See also Non-parametric statistics Sørensen–Dice coefficient References External links The Mantel test in ecology Statistical tests Nonparametric statistics Permutations