{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T04:23:48Z","timestamp":1760243028405,"version":"build-2065373602"},"reference-count":34,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2015,6,3]],"date-time":"2015-06-03T00:00:00Z","timestamp":1433289600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Games"],"abstract":"<jats:p>This paper analyzes the dynamic stability of moral codes in a two population trust game. Guided by a moral code, members of one population, the Trustors, are willing to punish members of the other population, the Trustees, who defect. Under replicator dynamics, adherence to the moral code has unstable oscillations around an interior Nash Equilibrium (NE), but under smoothed best response dynamics we obtain convergence to Quantal Response Equilibrium (QRE).<\/jats:p>","DOI":"10.3390\/g6020150","type":"journal-article","created":{"date-parts":[[2015,6,3]],"date-time":"2015-06-03T11:29:39Z","timestamp":1433330979000},"page":"150-160","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["How Moral Codes Evolve in a Trust Game"],"prefix":"10.3390","volume":"6","author":[{"given":"Jean","family":"Rabanal","sequence":"first","affiliation":[{"name":"Economics Department, Ball State University, 2000 W. University Ave. Muncie, IN 47306, USA"}]},{"given":"Daniel","family":"Friedman","sequence":"additional","affiliation":[{"name":"Department of Economics, University of California Santa Cruz, 1156 High Street, Santa Cruz, CA 95064, USA"}]}],"member":"1968","published-online":{"date-parts":[[2015,6,3]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"813","DOI":"10.1016\/j.geb.2008.10.006","article-title":"Equilibrium vengeance","volume":"66","author":"Friedman","year":"2009","journal-title":"Games Econ. Behav."},{"key":"ref_2","unstructured":"Friedman, D., and Sinervo, B. (2015). Evolutionary Games in Nature, Computers and Society, Oxford University Press."},{"key":"ref_3","unstructured":"Hauser, M.D. (2006). Moral Minds, Harper-Collins."},{"key":"ref_4","doi-asserted-by":"crossref","unstructured":"Friedman, D. (2008). 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