Parametric uncapacitated facility location

We consider the parametric Uncapacitated Facility Location Problem (UFLP) where the demand of each customer is allowed to vary over a certain interval. Despite the value of parametric analysis, no such efforts are found for the UFLP; this mainly seems to be due to the fact that parametric analysis usually requires the computation of a number of UFLPs with heavy computational burden. In this paper, we will show that the special structure of the UFLP provides a nice property for its parametric version, based on which an efficient branch and bound procedure for the parametric analysis is developed.