Comparison of MGR-MEDIAN and GRAPPA (three genomes nonequidistant from the ancestor). The genomes G ₁,G ₂, and G ₃ are obtained byk, k, and 2k reversals, respectively, each from the ancestral identity permutation 1 2 … n (n= 30 and n = 100). The simulations were repeated 10 times for every ratio #reversals/#markers = 4k/n. (a) and (b) show the average difference between the number of reversals on the tree recovered by the algorithm and the number of reversals on the actual tree (equal to 4k). (c) and (d) show the average reversal distance between the solution recovered and the actual ancestor.