We consider the following problem known as simultaneous geometric graph embedding (SGE). Given a set of planar graphs on a shared vertex set, decide whether the vertices can be placed in the plane inâ€¦ (More)

This paper concerns the reverse 2-median problem on trees and the reverse 1-median problem on graphs that contain exactly one cycle. It is shown that both models under investigation can beâ€¦ (More)

We study the problem of simultaneously embedding several graphs on the same vertex set in such a way that edges common to two or more graphs are represented by the same curve. This problem is knownâ€¦ (More)

We study the complexity of finding extreme pure Nash equilibria in symmetric (unweighted) network congestion games. In our context best and worst equilibria are those with minimum respectivelyâ€¦ (More)

Given n points in the plane with nonnegative weights, the inverse Fermat-Weber problem consists in changing the weights at minimum cost such that a prespecified point in the plane becomes theâ€¦ (More)

The convex ordered median problem is a generalization of the median, the k-centrum or the center problem. The task of the associated inverse problem is to change edge lengths at minimum cost suchâ€¦ (More)