ArticleProceedings of the National Academy of Sciences of the United States of America2020
Market integration accounts for local variation in generalized altruism in a nationwide lost-letter experiment.
Article in Proceedings of the National Academy of Sciences of the United States of America, 2020. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 8 papers.
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Who cites it
8 citing papers in PubMed.
- The Evolutionary-Ecological Basis of Xenophilia.Human nature (Hawthorne, N.Y.) · 2026Article
- Traditionalism mediates social learning: Biases in acceptance of novel health interventions among Himba pastoralists.Evolution, medicine, and public health · 2026Article
- Reciprocal exchanges across multilayered networks show an emerging patron-client system led by salaried households.Evolutionary human sciences · 2026Article
- Trust over repeated interactions: Majority group members generalize more from interactions with non-coethnic partners.PloS one · 2026Article
- Protecting Public Goods or Helping Free Riders? A Real-Life Moral Dilemma in Interethnic and Intraethnic Encounters.Psychological science · 2025Article
- Unraveling controversies over civic honesty measurement: An extended field replication in China.Proceedings of the National Academy of Sciences of the United States of America · 2023Article
- Trust within human-machine collectives depends on the perceived consensus about cooperative norms.Nature communications · 2023Article
- Market integration accounts for local variation in generalized altruism in a nationwide lost-letter experiment.Proceedings of the National Academy of Sciences of the United States of America · 2020Article
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Abstract
What explains variation in levels of prosocial behavior across communities? And are members of the ingroup and outgroup treated differently? According to evolutionary theories of generalized altruism, market integration should lead to greater levels of prosociality: Market exchange forces people to interact with unknown others, thus creating the conditions for the extension of prosocial behavior beyond close-knit circles to include outgroup members and strangers. Moving away from the evolutionary focus on cross-cultural variation, this article uses the market-integration hypothesis to explain intracultural variation in levels of prosociality in an advanced society. Taking advantage of an ideal setting, this study reports results from a large-scale, nationwide lost-letter experiment in which 5,980 letters were dispersed in a sample of 188 Italian communities. The study confirms the relevance of market integration in accounting for differences in levels of prosociality: In areas where market exchange is dominant, return rates are high. It also casts a light on the relationship between ingroup and outgroup prosociality: Return rates for both Italian and foreign recipients are the same; they vary together; and ingroup returns are highly predictive of outgroup returns at the community level.
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