A socio-relational basis of ''irrational'' cooperation: An experimental study with the selective-play paradigm

Experimental gaming researchers have recently realized that a larger context is important in which dyadic prisoner's dilemma (PD) relations are embedded. The main purpose of this study was to examine whether people facing a ''selective-play'' situation spontaneously adopt the out-for-tar strategy (OFT), which previous studies found the most effective in such a situation. OFT proscribes to (1) always cooperate, (2) keep playing with the current player as long as he/she cooperates, and (3) desert the partner as soon as he/she slops cooperating. Results of an experiment with 90 students, of groups of six or eight, showed that subjects who faced a high level of social uncertainty in fact spontaneously adopted the strategy, interacting with the same partner as long as he/she uncertainty kept only the third part of the strategy, leaving the relation with a defector, but not necessarily keeping interaction with a cooperative partner.