Abstract We study pure coordination games where in every outcome, all players have identical payoffs, ‘win’ or ‘lose’. We identify and discuss a range of ‘purely rational principles’ guiding the reasoning of rational players in such games and compare the classes of coordination games that can be solved by such players with no preplay communication or conventions. We observe that it is highly nontrivial to delineate a boundary between purely rational principles and other decision methods, such as conventions, for solving such coordination games.

We introduce versions of game-theoretic semantics (GTS) for Alternating-Time Temporal Logic (ATL). In GTS, truth is defined in terms of existence of a winning strategy in a semantic evaluation game, and thus the game-theoretic perspective appears in the framework of ATL on two semantic levels: on the object level in the standard semantics of the strategic operators, and on the meta-level where game-theoretic logical semantics is applied to ATL. We unify these two perspectives into semantic evaluation games specially designed for ATL. The game-theoretic perspective enables us to identify new variants of the semantics of ATL based on limiting the time resources available to the verifier and falsifier in the semantic evaluation game. We introduce and analyse an unbounded and (ordinal) bounded GTS and prove these to be equivalent to the standard (Tarski-style) compositional semantics. We show that in these both versions of GTS, truth of ATL formulae can always be determined in finite time, i.e., without constructing infinite paths. We also introduce a non-equivalent finitely bounded semantics and argue that it is natural from both logical and game-theoretic perspectives. * This paper is a substantially extended and revised version of the conference paper [8].

We develop a game-theoretic semantics (GTS) for the fragment ATL + of the Alternating-time Temporal Logic ATL * , essentially extending a recently introduced GTS for ATL. We show that the new game-theoretic semantics is equivalent to the standard compositional semantics of ATL + (with perfect-recall strategies). Based on the new semantics, we provide an analysis of the memory and time resources needed for model checking ATL + and show that strategies of the verifier that use only a very limited amount of memory suffice. Furthermore, using the GTS we provide a new algorithm for model checking ATL + and identify a natural hierarchy of tractable fragments of ATL + that extend ATL.