Fig. 6

Comparison of term enrichment between parent and child clusters in the CorEx hierarchy. a The distributions of GO term information content (IC) for all terms enriched in factor-defined gene groups show a relative overabundance of low information (lower specificity) terms for factors in the lowest layer (L1). GO term IC is calculated as the negative logarithm of the ratio of the number of descendants of a given term in the Gene Otology to the number of descendants of the root. b Relative enrichment of GO terms that are shared by child and parent nodes is compared by plotting the difference of the (log) term enrichment p-values, with p1 referring to the p-value for the lower L1 layer and p2 referring to the p-value for the upper L2 layer. A clear trend for increased enrichment of low information terms in parent nodes (L2), as one expects in a GO-like hierarchy