Multi-Unit Facility Location Games
  Facility location games have been a topic of major interest in economics, operations research and computer science, starting from the seminal work by Hotelling. In the classical pure location Hotelling game businesses compete for maximizing customer attraction by strategically locating their facilities, assuming no price competition, while customers are attracted to their closest facilities. Surprisingly, very little rigorous work has been presented on multi-unit facility location games, where the classical pure location Hotelling games are extended to contexts where each player is to locate several facilities. In this paper we present two major contributions to the study of multi-unit pure location Hotelling games. In the first part of this paper we deal with the two-player multi-unit setting, and fully characterize its equilibria. In the second part of this paper we deal with multi-unit facility location games, with $N\geq 3$ players; our main result in this part is the full characterization of the settings where pure strategy equilibria exist. Our results also extend classical results on necessary and sufficient conditions for a strategy profile to be in equilibrium in a pure location (single-unit) Hotelling game to multi-unit pure location games. 
Omer Ben-Porat and Moshe Tennenholtz
cs.GT