It pays to pay – Big Five personality influences onco-operative behaviour in an incentivized and hypotheticalprisoner’s dilemma game

The authors investigated how the presence or absence of monetary incentives in a prisoner’sdilemma game may influence research outcomes. Specifically, the predictive power of the BigFive personality traits on decisions in an incentivized (N = 60) or hypothetical (N = 60)prisoner’s dilemma game was investigated. Participants were less generous in theincentivized game. More importantly, personality predicted decisions only in the incentivizedgame, with low Neuroticism and high Openness to Experience predicting more cooperativetransfers. The influence of Neuroticism on behaviour in the incentivized game was mediatedby risk attitude. The results are consistent with other results suggesting that the Big Five arerelevant predictors of moral behaviour, and with results suggesting that the determinants ofhypothetical decisions are different from the determinants of real decisions, with the latterbeing more revealing of one’s true preferences. The authors argue that psychologists,contrary to prevailing praxis, should consider making their participants’ decisions more real.This could allow psychologists to more convincingly generalize laboratory findings intocontexts outside of the laboratory.