"Voluntarily Separable Prisoner's Dilemma with Reference Letters"

We consider voluntarily separable repeated Prisoner's Dilemma in which a pair of players meet randomly and repeatedly play Prisoner's Dilemma only by mutual agreement. Fujiwara-Greve and Okuno-Fujiwara (2007) consider the case that once a partnership is dissolved there is no information flow to other partnerships. We consider the case that players can issue a reference letter to the partner if they entered cooperation periods, but the content of a letter is not verifiable. We show that the sheer existence of a letter shortens the trust-building periods of new matches and thus improves efficiency in equilibrium.

On-site Energy Management by Integrating Campus Buildings and Optimizing Local Energy Systems ‒ Case Study of the Campus in Finland

This research describes the potential study on the impact of energy improvements of existing campus buildings by on-site energy management and operational strategies. The focus buildings in the campus were mainly built in the 1960s, and therefore it is time to carry out renovation work. In conjunction with the renovations, the aim is to improve the energy efficiency of the buildings, and to develop the functionality of the properties to meet the current requirements. Thus, in this study, the potentials of on-site energy generation and sharing in the cluster of campus buildings in Finland were studied. By means of optimisation method, the optimal combined heat and power systems capacity distribution and operation mode for minimizing annual primary energy consumption were simulated. The results show that the integration of buildings has an advantage of 23% of primary energy reduction for on-site energy management as compared with the present situation. Consequently, integrating buildings and optimizing on-site energy management can be one of effective strategies for minimizing primary energy consumption. Furthermore, the study to improve operation strategies of building service systems considering current space use in the buildings clarified that up to 13% of total energy use reduction is expected. The research work also proposes a way of providing environmental information to increase awareness of building energy usage in the campus

Voluntarily Separable Repeated Prisoner’s Dilemma.

Abstract: In Fujiwara-Greve and Okuno-Fujiwara (2009), an evolutionary stability concept was defined by allowing mutations of any strategy. However, in human societies, not all strategies are likely to be tried out when a player considers what happens in the future. In this paper we introduce the "shared belief" of potential continuation strategies, generated and passed on in a society, and mutations are restricted only among best responses against the shared belief. We show that a myopic strategy becomes a part of a bimorphic equilibrium under a shared belief and contributes to a higher payoff than ordinary neutrally stable distributions'

"Social Norms and Voluntary Cooperations"(in Japanese)

Unlike the ordinary repeated games, in the real world, people can run away after cheating. In this paper we construct a social game, in which players can repeat Prisoners' Dilemma only if both players agree to continue the partnership. We investigate how a social sanction prevents moral hazard in such a voluntary relationship. We have three conclusions. First, it is possible to enforce voluntary long-term cooperation by trust-building. Second, the trust-building periods can be shortened under diverse strategy distributions. Third, if there is a reference letter system which conveys information that a partnership ended by an unavoidable cause, then the trust-building periods can be shortened as well.

Document : Actions de soutien aux nikkeijin philippins

Suzuki Nobue, Le Bail Hélène. Document : Actions de soutien aux nikkeijin philippins. In: Ebisu, n°46, 2011. pp. 73-76

Voluntarily Separable Prisoner\u27s Dilemma with Reference Letters

We consider voluntarily separable repeated Prisoner\u27s Dilemma in which a pair of players meet randomly and repeatedly play Prisoner\u27s Dilemma only by mutual agreement. Fujiwara-Greve and Okuno-Fujiwara (2007) consider the case that once a partnership is dissolved there is no information flow to other partnerships. We consider the case that players can issue a reference letter to the partner if they entered cooperation periods, but the content of a letter is not verifiable. We show that the sheer existence of a letter shortens the trust-building periods of new matches and thus improves efficiency in equilibrium.本文フィルはリンク先を参照のこ

Voluntarily Separable Prisoner's Dilemma with Reference Letters

We consider voluntarily separable repeated Prisoner's Dilemma in which a pair of players meet randomly and repeatedly play Prisoner's Dilemma only by mutual agreement. Fujiwara-Greve and Okuno-Fujiwara (2007) consider the case that once a partnership is dissolved there is no information flow to other partnerships. We consider the case that players can issue a reference letter to the partner if they entered cooperation periods, but the content of a letter is not verifiable. We show that the sheer existence of a letter shortens the trust-building periods of new matches and thus improves efficiency in equilibrium

Voluntarily Separable Repeated Games with Social Norms

We extend the voluntarily separable repeated Prisoner\u27s Dilemma (Fujiwara-Greve and Okuno-Fujiwara, 2009) to continuous actions. We show that there is a (constrained) efficient bimorphic equilibrium which is robust under evolutionary pressure. It consists of a cooperative strategy and a myopic defection strategy so that our model provides a foundation to incomplete information models as well.本文フィルはリンク先を参照のこ