Hi, Does anybody know if the Ward agglomerative method is different from hclust to agnes functions ? This is the example given in the as.hclust help, but instead of using complete linkage, i use ward linkage. The clustering results from the both functions can change (depending on the random data), while they both use euclidean metric and ward linkage !! x <- matrix(rnorm(30), ncol=3) hc <- hclust(dist(x), method="ward") if(require(cluster, quietly=TRUE)) {# is a recommended package ag <- agnes(x, method="ward") hcag <- as.hclust(ag) ## The dendrograms order slightly differently: op <- par(mfrow=c(1,2)) plot(hc) ; mtext("hclust", side=1) plot(hcag); mtext("agnes", side=1) } If someone can explain the difference ... Thanks, Best, Nicolas S. -- Nicolas Servant Equipe Bioinformatique Institut Curie 26, rue d'Ulm - 75248 Paris Cedex 05 - FRANCE Email: Nicolas.Servant at curie.fr Tel: 01 53 10 70 55 http://bioinfo.curie.fr/