Continuous and Step-level Pay-off Functions in Public Good Games: A Conceptual Analysis

Conflicts between individuals’ and collective interests are ubiquitous in social life. Numerous experimental studies have investigated the resolution of such conflicts using public good games with either continuous or step-level payoff functions. A conceptual analysis using both classic game theory and social exchange theory shows that these two types of games are fundamentally different. A continuous function game is a social dilemma in that it contains a conflict between individual and collective interests whereas a step-level game is primarily a social coordination game. Thus, we conclude that one can not safely generalize results from step-level to continuous form games. Additionally, our analysis shows that the distinction between continuous and single-step games can be blurred by segmenting a continuous function into steps or adding steps to a single-step game. We identify characteristics of the payoff function that conceptually mark the transition from a dilemma to a coordination problem.

Information Flow and Influence during Collective Search, Discussion, and Choice

If decision-relevant information is distributed among team members, the group is inclined to focus on shared information and to neglect unshared information, resulting often in suboptimal decisions. This classical finding is robust in experimental settings, in which the distribution of information is created artificially by an experimenter. The current paper looks at information sharing effects when access to information is not restricted, and decision makers are very familiar with the decision task. We analyzed archival search and discussion data obtained from business executives completing a personnel selection exercise. Information popularity in the population from which groups were composed predicted number of group members accessing items during information searches and whether the group discussed the items. The number of group members who accessed an item predicted whether information was repeated during discussion, and repetition predicted which items were included on an executive summary. Moreover, cognitively central group members were more influential than cognitively peripheral members. One implication is that collective decision making amplifies what is commonly known at the expense of disseminating what is not.Information Sharing, Cognitive Centrality, Group Decision Making, Collective Choice, Archival Data

Continuous and step-level pay-off functions in public good games : a conceptual analysis

Conflicts between individuals’ and collective interests are ubiquitous in social life. Numerous experimental studies have investigated the resolution of such conflicts using public good games with either continuous or step-level payoff functions. A conceptual analysis using both classic game theory and social exchange theory shows that these two types of games are fundamentally different. A continuous function game is a social dilemma in that it contains a conflict between individual and collective interests whereas a step-level game is primarily a social coordination game. Thus, we conclude that one can not safely generalize results from step-level to continuous form games. Additionally, our analysis shows that the distinction between continuous and single-step games can be blurred by segmenting a continuous function into steps or adding steps to a single-step game. We identify characteristics of the payoff function that conceptually mark the transition from a dilemma to a coordination problem

Can neutron disappearance/reappearance experiments definitively rule out the existence of hidden braneworlds endowed with a copy of the Standard Model?

International audienceMany works, aiming to explain the origin of dark matter or dark energy, consider the existence of hidden (brane)worlds parallel to our own visible world — our usual Universe — in a multidimensional bulk. Hidden braneworlds allow for hidden copies of the Standard Model. For instance, atoms hidden in a hidden brane could exist as dark matter candidates. As a way to constrain such hypotheses, the possibility for neutron–hidden neutron swapping can be tested thanks to disappearance-reappearance experiments also known as passing-through-walls neutron experiments. The neutron-hidden neutron coupling g can be constrained from those experiments. While g could be arbitrarily small, previous works involving a M4×R1 bulk, with DGP branes, show that g then possesses a value which is reachable experimentally. It is of crucial interest to know if a reachable value for g is universal or not and to estimate its magnitude. Indeed, it would allow, in a near future, to reject definitively — or not — the existence of hidden braneworlds from experiments. In the present paper, we explore this issue by calculating g for DGP branes, for M4×S1/Z2, M4×R2 and M4×T2 bulks. As a major result, no disappearance-reappearance experiment would definitively universally rules out the existence of hidden worlds endowed with their own copy of Standard Model particles, except for specific scenarios with conditions reachable in future experiments

Late baryogenesis in a two-brane universe with a latent CP violation

We introduce a toy model of baryogenesis where our usual visible Universe is a 3-brane coevolving with a hidden 3-brane in a multidimensional bulk, in an ekpyrotic-like approach. The visible matter and antimatter sectors are coupled with the hidden matter and antimatter sectors, breaking the CP invariance and leading to baryogenesis occurring after the quark-gluon era. The issue of leptogenesis is also discussed. This model complements cosmological approaches in which dark matter and dark energy could naturally emerge from many-brane scenarios.Comment: 7 pages, 3 figures, submitte

Continuous versus Step-Level Public Good Games

We will firstly outline the rationale of a public good game and explain the distinction between a continuous public good game and a threshold public good game. As a vast majority of experimental research in social psychology on public good games has used threshold public good games, we will then outline the structure of a dilemma game with a provision point. Our point is that dilemma games with a provision point violate two important assumptions commonly held for public good games: a) there is always a conflict between the group’s interest and the individual’s interest; and b) an individual is always better off defecting. A threshold dilemma game is a dilemma with a coordination game embedded in it. Hence it provides focal point solutions and may as a consequence leave less room for other factors to affect behavior. Moreover, games with a provision point might yield different results than games without a provision point. We will argue that above that threshold dilemma games do not provide good models of many the public goods problems that are encountered in real life. We will propose that a public good game with a tilted S function provides a more appropriate model of real life dilemmas while fulfilling the defining properties of public good games

Information flow and influence during collective search, discussion, and choice

If decision-relevant information is distributed among team members, the group is inclined to focus on shared information and to neglect unshared information, resulting often in suboptimal decisions. This classical finding is robust in experimental settings, in which the distribution of information is created artificially by an experimenter. The current paper looks at information sharing effects when access to information is not restricted, and decision makers are very familiar with the decision task. We analyzed archival search and discussion data obtained from business executives completing a personnel selection exercise. Information popularity in the population from which groups were composed predicted number of group members accessing items during information searches and whether the group discussed the items. The number of group members who accessed an item predicted whether information was repeated during discussion, and repetition predicted which items were included on an executive summary. Moreover, cognitively central group members were more influential than cognitively peripheral members. One implication is that collective decision making amplifies what is commonly known at the expense of disseminating what is not

Information Sharing, Cognitive Centrality, and Influence among Business Executives during Collective Choice

Laboratory studies have shown that decision-making groups tend to focus on common information at the expense of unique information. In the current study, high level business executives completed a personnel selection task. Access to information about the candidates was not controlled as in a typical study of information sharing, but common, partially shared, and unique information arose naturally from the individual members’ information searches. During subsequent discussions, groups mentioned more common than partially shared than unique information. However, the underlying processes seemed to be different from what has been observed in laboratory studies. The popularity of information in the population from which groups were composed predicted both the number of a group’s members who accessed an item in their information searches and whether the group discussed the item. However, the number of group members who accessed an item did predict whether information was repeated during discussion, and repetition predicted which items were included on a final written summary. Finally, cognitively central group members were more influential than cognitively peripheral members