We measure a specific form of other-regarding behavior, costly cooperation with an anonymous other, among 645 subjects at a trucker training program in the Midwestern US. Using subjects' second-mover strategy in a sequential form of the Prisoners' Dilemma, we categorize subjects as: Free Rider,...

In the past decade, nearly 20 studies have found a strong, persistent pattern in surveys and behavioral experiments from over 40 countries: individual exposure to war violence tends to increase social cooperation at the local level, including community participation and prosocial behavior. Thus...

Spillovers of prosocial motivation are crucial for the formation of social capital. They facilitate interactions among individuals and create social multipliers that amplify the effects of policy interventions. We conducted a large-scale intervention study among dyads of blood donors to...

Among residents of an informal housing area in Cairo, we examine how dictator giving varies by the social distance between subjects - friend versus stranger - and by the anonymity of the dictator. While giving to strangers is high under anonymity, we find - consistent with Leider et al. (2009) -...

Concerns over the perceived negative impacts of computers on social development among children are prevalent but largely uninformed by plausibly causal evidence. We provide the first test of this hypothesis using a large-scale randomized control experiment in which more than one thousand...

It has been claimed that the market fosters selfishness and thereby undermines the moral basis of society. This thesis has been developed with an emphasis on market exchange. Everyday life is, however, predominantly shaped by interactions in the workplace rather than by shopping behaviour. This...

We combined a natural experiment (the occurrence of the COVID-19 pandemic in 2020) with the tools of laboratory experiments to study whether and how an unprecedented shock on social interactions (the introduction and abrogation of a nationwide lockdown) affected the evolution of individuals'...

Social networks are a key factor of success in life, but they are also strongly segmented on gender, ethnicity, and other demographic characteristics (Jackson, 2010). We present novel evidence on an understudied source of homophily, namely behavioral traits. Behavioral traits are important...

How do individuals shape societies? How do societies shape individuals? This paper develops a framework for studying the connections between micro and macro phenomena. The framework builds on two ingredients widely used in social science - population and variable. Starting with the simplest case...

We employ a standard identification strategy from the peer effects literature to investigate the importance of network definitions in estimation of endogenous peer effects. We use detailed information on friends in the Adolescent Longitudinal Health Survey (Add Health) to construct two network...