COVID-19 infection induces higher trust in strangers.

How does the COVID-19 pandemic affect interpersonal trust? Most evidence shows that natural disasters reinforce trust and cooperation, but the COVID-19 virus differs from other calamities, since it spreads through contact with people, potentially increasing suspicion and distrust, as, according to contemporaneous writers' accounts, seems to have been the case with the Black Death, the London plague, and the Spanish influenza. We investigate the link between interpersonal trust and individuals exposed to COVID-19, either vicariously through their community or networks or directly by becoming infected. We rely on an original panel survey, including a survey experiment, with a representative sample of adults in Italy, one of the countries hardest struck by the pandemic. Our experimental findings reveal that priming people about the risk that the pandemic poses to their health leads to a substantial increase in their trust in strangers. Our panel data analysis of within-individual effects shows that those who become infected trust strangers more than those who are not infected. Our findings could be explained by people observing higher than expected altruistic behavior or becoming more dependent on other people's support, consistent with the "emancipation theory of trust." When people recover from COVID-19, however, they drop to trusting strangers as much as those who were not directly exposed to the virus, an indication that the positive effects on trust during the pandemic have an emotional source. Nonetheless, the evidence suggests that, in the aggregate, there has been a small but significant increase in trust among the general population relative to prepandemic levels.

Does information about toughness decrease fighting? Experimental evidence.

Will fights erupt when resources are scarce and the rules regulating their distribution are absent or ignored? We conjecture that the answer depends on whether credible information about individuals' toughness is available. When people send credible signs and signals of their toughness disputes may be solved without violence. We use a laboratory experiment in which subjects create information about their toughness and decide whether to take others' resources and resist in case others' attempt to take theirs. Subjects perform a potentially painful but safe physical exercise to create information and to determine who wins and loses fights. This, realistically, ranks subjects according to their toughness and implicates toughness, a quality important in real conflict, in fighting. We find that, consistent with theory, information reduces fighting. This suggests that, in addition to the theories traditionally used to explain prisoner behavior, the availability of credible information about toughness influences prison conflict.

Natural and strategic generosity as signals of trustworthiness.

We exploit the fact that generosity and trustworthiness are highly correlated and the former can thus be a sign of the latter. Subjects decide between a generous and a mean split in a dictator game. Some of them are informed from the start that afterwards they will participate in a trust game and that their choice in the dictator game may matter; others are not informed in advance. In the trust game, before trusters decide whether or not to trust, some trustees can reveal (or conceal) only their true choice in the dictator game, while others can say to trusters, truthfully or otherwise, what they chose. We find that a generous choice made naturally by uninformed trustees and reliably revealed is more effective in persuading trusters to trust than a generous choice that could be strategic or a lie. Moreover, we find that, when they can, mean subjects lie and go on to be untrustworthy.