Figure 2

Null distribution of tightness. The null distribution of node tightness S depends on the number of leaves. The empirical probability density distributions for the Simulated6 set with (1 - Pearson correlation) dissimilarity – average linkage combination (A) and for the Organelles set with (1 - Pearson correlation) dissimilarity – Ward linkage combination (B) are shown, for three different values of the number of leaves in each case. Each plot is based on 5000 randomizations of the respective data set.