Raising the Minimum in the Minimal Group Paradigm

Race, diversity and pro-social behavior in a segmented society

“…If identity on its own was sufficient to produce in-group favoritism (as predicted by social identity theory), then the bias should have appeared in both treatments, but Yamagishi et al (1999) found that an in-group bias only emerged in the latter case where group membership was mutually known. This was attributed to multilateral fate control or interdependence in the outcomes of group members (Yamagishi et al, 1999;Karp et al, 1993;Rabbie et al, 1989). In other words, proposers favor in-group members because they expect that this favorable behavior will be reciprocated by in-group members when group identity is known, thus making the outcomes for group members interdependent.…”

A Bayesian model of quasi-magical thinking can explain observed cooperation in the public good game

“…The principle of using a Bayesian model of conditional expected utility also provides a general framework for analyzing any game, at least in principle. We have described here how the model is supported at least qualitatively by results in other games, such as the Prisoner's dilemma (Morris and Sim, 1998;Shafir and Tversky, 1992), Newcomb's problem (Nozick, 1969) and experiments on group identity (Karp et al, 1993;Rabbie et al, 1989).…”

“…Other puzzling data come from experiments on group identity (Karp et al, 1993;Rabbie et al, 1989). Players are divided into two groups based on highly arbitrary criteria such as the alleged tendency to underestimate or overestimate dots on a screen or aesthetic preference between the artists Klee and Kandinsky.…”

Symbols, Group Identity and the Hold-Up Problem

“…This is supported by the finding of Karp, Jin, Yamagishi & Shinotsuka (1993) who removed the interdependence of payoffs from the design by paying the decision-maker a fixed amount. Such change in design lead to no preferential treatment of ingroup members.…”