— We treat a discrete uncapacitated facility location problem where the installation cost per facility is a gênerai nonlinear function of the number of established facilities. Assuming a convexity proper ty, Mirchandani and Jagannathan developed a heur is tic solution procedure for this problem. Hère, we show how to modify their algorithm in order to get and prove exact solutions and, at the sa...

We study stochastic bilevel programs where the leader chooses a binary here-and-now decision and the follower responds with a continuous wait-and-see-decision. Using modern decision rule approximations, we construct lower bounds on an optimistic version and upper bounds on a pessimistic version of the leader’s problem. Both bounding problems are equivalent to explicit mixedinteger linear progra...

It is critical to locate facilities in the retail operations, especially in competitive environment. In most competitive location models available in the literatures, demand is assumed to be fixed or random regardless of market conditions. However, demand is related to the number of facilities, service capacity or the distance from the facility to the customer, which is considered in few litera...