(Elsevier, 2009-03-06) Marín Pérez, Alfredo; Nickel, Stefan; Puerto Albandoz, Justo; Velten, Sebastian; Universidad de Sevilla. Departamento de Estadística e Investigación Operativa; Comunidad Autónoma de Murcia; Universidad de Sevilla. FQM331: Métodos y Modelos de la Estadística y la Investigación Operativa
Flexible discrete location problems are a generalization of most classical discrete locations problems like p-median or p-center problems. They can be modeled by using so-called ordered median functions. These functions multiply a weight to the cost of fulfilling the demand of a customer, which depends on the position of that cost relative to the costs of fulfilling the demand of other customers. In this paper a covering type of model for the discrete ordered median problem is presented. For the solution of this model two sets of valid inequalities, which reduces the number of binary variables tremendously, and several variable fixing strategies are identified. Based on these concepts a specialized branch & cut procedure is proposed and
extensive computational results are reported.
