An Algorithm for the Multi-Stage Stochastic Relief Routing Problem

There is usually uncertainty in the information during a disaster. These uncertainties are revealed in different stages during the time, but they still exist. Therefore, when information is appeared over the time, it is necessary to model and solve the problem in a multi-stage stochastic programming to make more real decisions. In this paper, a multi-stage relief routing model is presented for a disaster problem. It is assumed that the routing plan can be rerouted in each stage according to new received information. Also, an approximation algorithm is presented based on the two-stage stochastic programming. It is shown that the proposed algorithm is an appropriate approximation of the multi-stage model. Comparison of results with the deterministic model indicates that more survivors will be achieved by the proposed model comparing to the deterministic one and it shows effectiveness of the proposed approach.