  Multi-agent cooperation is an important topic, and is particularly
challenging in mixed-motive situations where it does not pay to be nice to
others. Consequently, self-interested agents often avoid collective behaviour,
resulting in suboptimal outcomes for the group. In response, in this paper we
introduce a metric to quantify the disparity between what is rational for
individual agents and what is rational for the group, which we call the general
self-interest level. This metric represents the maximum proportion of
individual rewards that all agents can retain while ensuring that achieving
social welfare optimum becomes a dominant strategy. By aligning the individual
and group incentives, rational agents acting to maximise their own reward will
simultaneously maximise the collective reward. As agents transfer their rewards
to motivate others to consider their welfare, we diverge from traditional
concepts of altruism or prosocial behaviours. The general self-interest level
is a property of a game that is useful for assessing the propensity of players
to cooperate and understanding how features of a game impact this. We
illustrate the effectiveness of our method on several novel games
representations of social dilemmas with arbitrary numbers of players.

Computer Science and Game Theory