Dear all, I have R code of the following form: wilcox_test(categoricalResponse ~ binaryTreatment | matchedCluster) The data consist of 11 matched pairs of clusters, each of which contains a variable number of units on which the response variable is measured. Treatment, however, was assigned at the level of the cluster. First, is there any way to make `wilcox_test' calculate p-value based on the permutation distribution of the _clusters_, rather than treating all units in each stratum as independent? Second, does the function `wilcox_test' (and similar functions like `surv_test') in the `coin' package weights the linear statistic in each stratum by 1/(N_s + 1), where N_s is the number of observations in the stratum, as is suggested by van Elteren (1960)? Thank you for your assistance. Devin --- Devin M. Caughey PhD Candidate, Political Science IGERT-PEPPP Fellow UC Berkeley, 210 Barrows Hall, Berkeley, CA 94720-1950 caughey at berkeley.edu www.devincaughey.com