The phenomenon of predating predators requires at least three specimens to whom we refer as players 1, 2, and 3. Player 1 has simply to guess nature when trying to find food. Player 2 is hunting player 1 in the hope that 1 is well fed but must also avoid being hunted by player 3. One major...

Experimental studies have shown that trust and reciprocity are effective in increasing efficiency when complete contracting is infeasible. One example is the study by Berg et al. (1995) of the investment game. In this game the person who receives the investment is the one who may reward the...