Superadditive Coalitional Game

A coalitional game is superadditive if disjoint coalitions can do at least as well by merging. Formally, for disjoint coalitions $S,T \subseteq N$, $$ v(S \cup T) \ge v(S) + v(T). $$

Superadditivity is a basic economic compatibility condition: it says there is no loss of worth merely from allowing two non-overlapping coalitions to coordinate as one larger coalition.

References

• [MSZ Ch.16, Def 16.8] Maschler, Solan, Zamir, Game Theory.