Direct Reciprocity and Costly Punishment: Generous Tit-for-Tat Prevails Newer:Dynamic Remodeling of In-Group Bias During the 2008 Presidential ElectionOlder:Decision-Making in Research Tasks With Sequential Testing PostedJuly 25, 2013 AuthorScienceSites Categoriesgame-theory-systems-model, 2009, journal-article Tags2009, Cooperation, Punishment, Repeated games, Computer models