This paper studies a three player hierarchical differential game (with a large country, a small country, and a terrorist organization), to analyze the actual European refugee situation. Terrorists may enter Europe as refugees, taking advantage of the Open Door Policy, to attack both countries....

Crowdfunding platforms are providing funds to an increasing number of projects, among which many have a strong social/community impact. Under a all-or-nothing program, the success of the investment depends on the ability of a crowd of potential investors to put their funds into the project...