{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,17]],"date-time":"2025-11-17T21:34:33Z","timestamp":1763415273257,"version":"3.41.0"},"reference-count":14,"publisher":"Association for Computing Machinery (ACM)","issue":"2","license":[{"start":{"date-parts":[[2011,6,1]],"date-time":"2011-06-01T00:00:00Z","timestamp":1306886400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/www.acm.org\/publications\/policies\/copyright_policy#Background"}],"content-domain":{"domain":["dl.acm.org"],"crossmark-restriction":true},"short-container-title":["SIGecom Exch."],"published-print":{"date-parts":[[2011,6]]},"abstract":"<jats:p>A longstanding idea in the literature on human cooperation is that cooperation should be reinforced when conditional cooperators are more likely to interact. In the context of social networks, this idea implies that cooperation should fare better in highly clustered networks such as cliques than in networks with low clustering such as random networks. To test this hypothesis, we conducted a series of experiments on Amazon Mechanical Turk, in which 24 individuals played a local public goods game arranged on one of five network topologies that varied between disconnected cliques and a random regular graph. In contrast with previous work, we found that network topology had no significant effect on average contributions. This result implies either that individuals are not conditional cooperators, or else that cooperation does not benefit from positive reinforcement between connected neighbors. We then tested both of these possibilities in two subsequent series of experiments in which artificial \"seed\" players were introduced, making either full or zero contributions. First, we found that although players did generally behave like conditional cooperators, they were as likely to decrease their contributions in response to low contributing neighbors as they were to increase their contributions in response to high contributing neighbors. Second, we found that positive effects of cooperation did not spread beyond direct neighbors in the network. In total we report on 113 human subjects experiments, highlighting the speed, flexibility, and cost-effectiveness of web-based experiments over those conducted in physical labs.<\/jats:p>","DOI":"10.1145\/1998549.1998550","type":"journal-article","created":{"date-parts":[[2011,6,21]],"date-time":"2011-06-21T13:47:26Z","timestamp":1308664046000},"page":"3-8","update-policy":"https:\/\/doi.org\/10.1145\/crossmark-policy","source":"Crossref","is-referenced-by-count":16,"title":["Cooperation and contagion in web-based, networked public goods experiments"],"prefix":"10.1145","volume":"10","author":[{"given":"Siddharth","family":"Suri","sequence":"first","affiliation":[{"name":"Yahoo! Research"}]},{"given":"Duncan J.","family":"Watts","sequence":"additional","affiliation":[{"name":"Yahoo! Research"}]}],"member":"320","published-online":{"date-parts":[[2011,6]]},"reference":[{"key":"e_1_2_1_1_1","doi-asserted-by":"crossref","unstructured":"Axelrod R. and Hamilton W. D. 1981. The evolution of cooperation. Science 211 4489 1390--1396.  Axelrod R. and Hamilton W. D. 1981. The evolution of cooperation. Science 211 4489 1390--1396.","DOI":"10.1126\/science.7466396"},{"volume-title":"The evolution of cooperation","author":"Axelrod R. M.","key":"e_1_2_1_2_1","unstructured":"Axelrod , R. M. 1984. The evolution of cooperation . Basic Books , New York . Axelrod, R. M. 1984. The evolution of cooperation. Basic Books, New York."},{"key":"e_1_2_1_3_1","doi-asserted-by":"publisher","DOI":"10.1257\/aer.90.4.980"},{"key":"e_1_2_1_4_1","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.0913149107"},{"key":"e_1_2_1_5_1","doi-asserted-by":"publisher","DOI":"10.1080\/0022250X.1993.9990112"},{"key":"e_1_2_1_6_1","doi-asserted-by":"publisher","DOI":"10.1016\/0022-5193(64)90039-6"},{"key":"e_1_2_1_7_1","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.0808147106"},{"key":"e_1_2_1_8_1","doi-asserted-by":"crossref","unstructured":"Kearns M. Suri S. and Montfort N. 2006. An experimental study of the coloring problem on human subject networks. Science 313 5788 824--827.  Kearns M. Suri S. and Montfort N. 2006. An experimental study of the coloring problem on human subject networks. Science 313 5788 824--827.","DOI":"10.1126\/science.1127207"},{"key":"e_1_2_1_9_1","doi-asserted-by":"publisher","DOI":"10.1137\/S003614450342480"},{"key":"e_1_2_1_10_1","doi-asserted-by":"publisher","DOI":"10.1098\/rstb.2009.0215"},{"key":"e_1_2_1_11_1","doi-asserted-by":"crossref","unstructured":"Strogatz S. H. 2001. Exploring complex networks. Nature 410 6825 268--276.  Strogatz S. H. 2001. Exploring complex networks. Nature 410 6825 268--276.","DOI":"10.1038\/35065725"},{"key":"e_1_2_1_12_1","doi-asserted-by":"publisher","DOI":"10.1515\/9780691188331"},{"key":"e_1_2_1_13_1","doi-asserted-by":"publisher","DOI":"10.1126\/science.1070120"},{"key":"e_1_2_1_14_1","doi-asserted-by":"crossref","unstructured":"Watts D. J. and Strogatz S. H. 1998. Collective dynamics of 'small-world' networks. Nature 393 6684 440--442.  Watts D. J. and Strogatz S. H. 1998. Collective dynamics of 'small-world' networks. Nature 393 6684 440--442.","DOI":"10.1038\/30918"}],"container-title":["ACM SIGecom Exchanges"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/dl.acm.org\/doi\/10.1145\/1998549.1998550","content-type":"unspecified","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/dl.acm.org\/doi\/pdf\/10.1145\/1998549.1998550","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,6,18]],"date-time":"2025-06-18T11:06:13Z","timestamp":1750244773000},"score":1,"resource":{"primary":{"URL":"https:\/\/dl.acm.org\/doi\/10.1145\/1998549.1998550"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2011,6]]},"references-count":14,"journal-issue":{"issue":"2","published-print":{"date-parts":[[2011,6]]}},"alternative-id":["10.1145\/1998549.1998550"],"URL":"https:\/\/doi.org\/10.1145\/1998549.1998550","relation":{},"ISSN":["1551-9031"],"issn-type":[{"type":"electronic","value":"1551-9031"}],"subject":[],"published":{"date-parts":[[2011,6]]},"assertion":[{"value":"2011-06-01","order":2,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}]}}