dc.contributor.author Berman, Oded en_US dc.contributor.author Bertsimas, Dimitris J. en_US dc.contributor.author Larson, Richard C., 1943- en_US dc.date.accessioned 2004-05-28T19:36:21Z dc.date.available 2004-05-28T19:36:21Z dc.date.issued 1992-11 en_US dc.identifier.uri http://hdl.handle.net/1721.1/5374 dc.description Revised November 1992 en_US dc.description.abstract Discretionary service facilities are providers of products and/or services that are purchased by customers who are traveling on otherwise pre-planned trips such as the daily commute. Optimum location of such facilities requires them to be at or near points in the transportation network having sizable flows of different potential customers. In [1] a first version of this problem was formulated, assuming that customers would make no deviations, no matter how small, from the pre-planned route to visit a discretionary service facility. Here the model is generalized in a number of directions, all sharing the property that the customer may deviate from the pre-planned route to visit a discretionary service facility. Three different generalizations are offered, two of which can be solved approximately by greedy heuristics and the third by any approximate or exact method used to solve the pmedian problem. It is shown for those formulations yielding to a greedy heuristic approximate solution, including the formulation in [1], that the problems are examples of optimizing submodular functions for which the Nemhauser et. al. [51 bound on the performance of a greedy algorithm holds. In particular, the greedy solution is always within 37% of optimal, and for one of the formulations it is proved that the bound is tight. en_US dc.format.extent 1207391 bytes dc.format.mimetype application/pdf dc.language.iso en_US en_US dc.publisher Massachusetts Institute of Technology, Operations Research Center en_US dc.relation.ispartofseries Operations Research Center Working Paper;OR 271-92 en_US dc.title Locating Discretionary Service Facilities II: Maximizing Market Size, Minimizing Inconvenience en_US dc.type Working Paper en_US
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