Why is private investment so low in Gulf compared to Western countries? We investigate cross-regional differences in trust and reference points for trustworthiness as possible factors. Experiments controlling for cross-regional differences in institutions and beliefs about trustworthiness reveal that Gulf citizens pay much more than Westerners to avoid trusting, and hardly respond when returns to trusting change. These differences can be explained by subjects' gain/loss utility relative to their region's reference point for trustworthiness. The relation-based production of trust in the Gulf induces higher levels of trustworthiness, albeit within groups, than the rule-based interactions prevalent in the West.

We study how conflict in contest games is influenced by rival parties being groups and by group members being able to punish each other. Our motivation stems from the analysis of sociopolitical conflict. The theoretical prediction is that conflict expenditures are independent of group size and of whether punishment is available. We find, first, that conflict expenditures of groups are substantially larger than those of individuals, and both are above equilibrium. Second, allowing group members to punish each other leads to even larger conflict expenditures. These results contrast with those from public goods experiments where punishment enhances efficiency.

Due to betrayal aversion, people take risks less willingly when the agent of uncertainty is another person rather than nature. Individuals in six countries (Brazil, China, Oman, Switzerland, Turkey, and the United States) confronted a binary-choice trust game or a risky decision offering the same payoffs and probabilities. Risk acceptance was calibrated by asking individuals their “minimum acceptable probability” (MAP) for securing the high payoff that would make them willing to accept the risky rather than the sure payoff. People's MAPs are generally higher when another person, rather than nature, determines the outcome. This indicates betrayal aversion.