Heuristic procedures for solving the discrete ordered median problem

We present two heuristic methods for solving the Discrete Ordered Median Problem (DOMP), for which no such approaches have been developed so far. The DOMP generalizes classical discrete facility location problems, such as the p-median and p-center. The first procedure proposed in this paper is based on a genetic algorithm by Moreno Vega for p-median and p-center problems. Additionally, a second heuristic approach based on the Variable Neighborhood Search metaheuristic proposed by Hansen and Mladenović for the p-median problem is described. An extensive numerical study is presented to show the efficiency of both heuristics and compare them.