Technical Note—Branch and Fathom: A Technique for Computing Functions on the Power Set of a Set

Tree traversal algorithms are frequently used for ordering operations on sets. This paper describes a tree structure and traversal scheme which is applied to the computation of a reliability measure. The key to this variation is a particular labeling of the enumeration tree which locates supersets of a set S in one subtree of the node labeled with S. Exact computation by simple techniques is considerably more time-consuming than by the “branch and fathom” technique, which may also be useful in computing other functions on the power set of a set.