title: Transient nature of cooperation by pay-it-forward reciprocity.
abstract: Humans often forward kindness received from others to strangers, a phenomenon called the upstream or pay-it-forward indirect reciprocity. Some field observations and laboratory experiments found evidence of pay-it-forward reciprocity in which chains of cooperative acts persist in social dilemma situations. Theoretically, however, cooperation based on pay-it-forward reciprocity is not sustainable. We carried out laboratory experiments of a pay-it-forward indirect reciprocity game (i.e., chained gift-giving game) on a large scale in terms of group size and time. We found that cooperation consistent with pay-it-forward reciprocity occurred only in a first few decisions per participant and that cooperation originated from inherent pro-sociality of individuals. In contrast, the same groups of participants showed persisting chains of cooperation in a different indirect reciprocity game in which participants earned reputation by cooperating. Our experimental results suggest that pay-it-forward reciprocity is transient and disappears when a person makes decisions repeatedly, whereas the reputation-based reciprocity is stable in the same situation.
authors.affiliation: National Institute of Informatics, 2-1-2 Hitotsubashi, Chiyoda-ku, Tokyo 101-8430, Japan.|JST, ERATO, Kawarabayashi large graph project, c/o Global Research Center for Big Data Mathematics, NII, 2-1-2 Hitotsubashi, Chiyoda-ku, Tokyo 101-8430, Japan.
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Horita
authors.affiliation: Department of Behavioral Science, Hokkaido University, N10W7, Kita-ku, Sapporo, 060-0810, Japan.|Center for Experimental Research in Social Sciences, Hokkaido University, N10W7, Kita-ku, Sapporo, 060-0810, Japan.
authors.forename: Masanori
authors.initials: M
authors.lastname: Takezawa
authors.affiliation: Department of Behavioral Science, Hokkaido University, N10W7, Kita-ku, Sapporo, 060-0810, Japan.
authors.forename: Takuji
authors.initials: T
authors.lastname: Kinjo
authors.affiliation: Department of Behavioral Science, Hokkaido University, N10W7, Kita-ku, Sapporo, 060-0810, Japan.
authors.forename: Yo
authors.initials: Y
authors.lastname: Nakawake
authors.affiliation: Department of Engineering Mathematics, University of Bristol, Merchant Venturers Building, Woodland Road, Clifton, Bristol BS8 1UB, United Kingdom.
authors.forename: Naoki
authors.initials: N
authors.lastname: Masuda
mesh_terms: D000465:Algorithms; D003299:Cooperative Behavior; D005260:Female; D005716:Game Theory; D006801:Humans; D008297:Male; D015233:Models, Statistical; D012919:Social Behavior