Fig. 4
From: Inferring duplication episodes from unrooted gene trees
Illustration of gnaw for U with a double edge. Here, τ denotes the root of S. Assume that S has two positive lambda’s computed in line 7 by Algorithm 1: λ(α)=2 and λ(β)=1. Every edge e=〈u,v〉 of the plateau is split into two directed edges: 〈u,v〉 and 〈v,u〉. Each directed edge 〈u,v〉 is decorated with the lca-mapping M〈u,v〉(v) and me(u,v). For example, τ6 denotes the lca-mapping to τ and me(u,v)=〈τ,6〉. Here, gnaw returns 3+1+3 induced by the marked edge