Note on: “A Linear-Time Algorithm for Computing K -Terminal Reliability in Series-Parallel Network”

In an original and very interesting paper (Satyanarayana and Wood [1]) concerning polygon-to-chain reductions in a stochastic network, a small inconsistency occurs in the proof of Theorem 1. In particular, this happens in cases where the whole set of K-vertices lies in the remaining polygon. Such an example is the case of polygon type 5, where the appropriate note has been made by the authors for | K| = 2. Analogous notes must also be made for polygon types 4, 6, and 7, when K = 2,3, and 4, respectively. The correct transformations are given in Table 1 (note that dark vertices are K-vertices).