  This paper extends the theory of subset team games, a generalization of
cooperative game theory requiring a payoff function that is defined for all
subsets of players. This subset utility is used to define both altruistic and
selfish contributions of a player to the team. We investigate properties of
these games, and analyze the implications of altruism and selfishness for
general situations, for prisoner's dilemma, and for a specific game with a
Cobb-Douglas utility.
