Figure 1
Optimal candidate trees do not always display reducible sets. Top row: An input profile P = (t1, t2, t3) where {b, d} and {b, e} are reducible sets. Second and third rows: Two optimal representative selections. Fourth row: Optimal candidate trees corresponding to the representative selections in rows two and three. Neither candidate tree contains the cluster {b, d}, although they both contain {b, e}.