We study individuals who can choose how to compete with an opponent for one nonzero payoff. They can either nudge themselves into a fair set of rules where they have the same information and actions as their opponent, or into unfair rules where they spy, sabotage or fabricate their opponent's...

We analyze whether subjects with extensive laboratory experience and first-time participants, who voluntarily registered for the experiment, differ in their behavior. Subjects play four one-shot, two-player games: a trust game, a beauty contest, an ultimatum game, a travelers' dilemma and, in...