Approximation algorithm for two-stage stochastic fault-tolerant facility location problem

In this paper, we consider the two-stage stochastic fault-tolerant facility location problem with uniform connectivity demand (2-SFTFLPUCD). We present the currently best known approximation ratio 1.8526 for 2-SFTFLPUCD. Initially, we demonstrate a stronger result of the 3-approximation algorithm based on analysis of the sum of opening and connection cost. Subsequently, we seed a greedy augmentation algorithm with the solution of a 3-approximation algorithm to yield an improved approximation ratio.