Suppose a rooted tree T is given for preprocessing. The level-ancestor problem is to answer quickly queries of the following form. Given a vertex v and an integer i > 0, find the ith vertex on the path from the root to v. Algorithms that achieve a linear time bound for preprocessing and a constant time bound for a query have been published by Dietz (1991), Alstrup and Holm (2000), and Bender an...

Richmond & Strait (2000) have attracted much attention with a recent morphometric analysis of distal radii of anthropoids and hominid fossils, suggesting some of the latter share knuckle-walking traits. Several aspects of their treatment deserve comment. These authors show A.L. 288-1q,v and the putative hominid fossil KNM-ER 20419 falling near chimpanzees and gorillas in a canonical analysis of...

A directed acyclic graph (DAG) partially represents the conditional independence structure among observations of a system if the local Markov condition holds, that is if every variable is independent of its non-descendants given its parents. In general, there is a whole class of DAGs that represents a given set of conditional independence relations. We are interested in properties of this class...

Those who work at the interface of development and evolution are united by the conviction that developmental comparisons can shed light on both the evolution of specific morphologies and the macroevolutionary process itself. In practice, however, the field comprises a diversity of approaches. As the field grows and practitioners attempt to digest a growing mountain of comparative data, the vari...

Perfect simulation of an one-dimensional loss network on R with length distribution π and cable capacity C can performed using the clan of ancestors method. Domination of the clan of ancestors by a branching process with dependency in two generations improves the known sufficient conditions for the perfect scheme to be applicable.

Development of ozone (O3)-resistant cultivars is a potentially important approach for maintaining crop productivity under future climate scenarios inwhich tropospheric O3 pollution is projected to rise. A first step in the breeding of resistant cultivars for a crop such as soybean (Glycine max (L.) Merr.) is identification of sources of O3 resistance genes. Thirty ancestral lines of soybean wer...