Sequential commitment games

We consider an extensive-form game in which players have the option to commit to actions before the game is played. We focus on commitment procedures where players make voluntary irreversible commitments in a prescribed order over the decision nodes. We study whether such commitment procedures may lead to Pareto-efficient outcomes. Our main result is surprisingly positive: for two-player games, we introduce an order over the decision nodes for which the unique subgame perfect equilibrium outcome is Pareto-efficient for every strict preference of the players over the outcomes. We show that the above result does not hold for games with four players.