A tree must be acyclic, meaning it should not contain any cycles. A cycle is a path that starts and ends at the same vertex without repeating edges. The presence of a cycle indicates that there are ...

Journal of Applied Probability, Vol. 29, No. 3 (Sep., 1992), pp. 745-749 (5 pages) The dependence of coincidence of the global, local and pairwise Markov properties on the underlying undirected graph ...

The aim of this research therefore was to streamline the understanding of typical causal structures in both randomized and nonrandomized clinical trials in oncology, presenting concise guidelines for ...

A real variate is defined for the ordered pairs of nodes in a finite graph. We consider the problem of estimating the total of the variate values from the information provided by a node sample. The ...