Figure 4

Pheromone response pathway in yeast: the dendrogram of the clustering method UPGMA (distance measure: Tanimoto), with the optimal partition indicated by the cluster validity measure, Silhouette Width (SW). The leaves of the dendrogram correspond to t-invariants. The composition of the t-invariants, based on the transitions, is represented in the subjacent table. The transitions included in a given t-invariant are marked with an asterisk. T-invariants belonging to the same t-cluster, as indicated by the cluster validity measure, Silhouette Width, are of identical color. The transitions characterizing a given t-cluster (i.e. transitions that exactly participate in all t-invariants of the t-cluster) are framed in red.