“…A coreless game is unstable (Serrano 2007, p. 7); in other words, in such a game, players may form and leave coalitions each time their interests are not ensured. Game theorists demonstrated that the conditions for the core exists ï i.e., the core is non-empty ï is that the game is convex (see e.g., Dehez, 2017;Gilles, 2010, p. 53;Pechersky, 2015;Shapley, 1965Shapley, , p. 15, 1971.…”