Fig. 2
From: Rooting phylogenetic trees under the coalescent model using site pattern probabilities
Example of scoring potential root psitions on larger phylogenies. a A six-leaf unrooted species tree. The branches are coded from a to i, and the internal branches are highlighted in red; b An example species quartet ABCF. If the root is determined to be on branch a, f or h, the corresponding branch on the tree in a will get score 1. If the root is determined to be on branch b+g (or c+l), branches b and g, (or c and l) in a will each get score 0.5. c An example species quartet AECD. If the root is determined to be on branch a, c or d, the corresponding branch in a will get score 1. Otherwise, if the root is determined to be on branch e+g (or h+l), branches e and g (or h and l) will each get score 0.5