nep-gth New Economics Papers
on Game Theory
Issue of 2005‒04‒03
ten papers chosen by
Gerald Pech
NUI Galway

  1. The Folk Theorem for Games with Private, Almost-Perfect Monitoring By Johannes Horner; Wojciech Olszewski
  2. Social Games: Matching and the play of finitely repreated games By Jackson, Matthew O.; Watts, Alison
  3. Time to complete and research joint ventures : a differential game approach By Navas,Jorge; Kort,Peter M.
  4. The Agents-are-Substitutes Property in Continuous Generalized Assignment Problems By Lok,Reinder B.; Romero Morales,Dolores; Vermeulen,Dries
  5. On Committees of Experts By Bauke Visser; Otto H. Swank
  6. Trust, Trust Games and Stated Trust: Evidence from Rural Bangladesh By Johansson-Stenman, Olof; Mahmud, Minhaj; Martinsson, Peter
  7. Trust and Religion: Experimental Evidence from Bangladesh By Johansson-Stenman, Olof; Mahmud, Minhaj; Martinsson, Peter
  8. Coordination Failure in Repeated Games with Almost-Public Monitoring By George J. Mailath; Stephen Morris
  9. Ratifiability of Efficient Collusive Mechanisms in Second-Price Auctions with Participation Costs By Guofu Tan; Okan Yilankaya
  10. Equilibria in Second Price Auctions with Participation Costs By Guofu Tan; Okan Yilankaya

  1. By: Johannes Horner; Wojciech Olszewski
    Date: 2005–03–25
  2. By: Jackson, Matthew O.; Watts, Alison
    Abstract: We examine a new class of games, which we call social games, where players not only choose strategies but also choose with whom they play. A group of players who are dissatisfied with the play of their current partners can join together and play a new equilibrium. This imposes new refinements on equilibrium play, where play depends on the relative populations of players in different roles, among other things. We also examine finite repetitions of games where players may choose to rematch in any period. Some equilibria of fixed-player repeated games cannot be sustained as equilibria in a repeated social game. Conversely, the set of repeated matching (or social) equilibria also includes some plays that are not part of any subgame perfect equilibrium of the corresponding fixed-player repeated games. We explore existence under different equilibrium definitions, as well as the relationship to renegotiation-proof equilibrium. It is possible for repeated matching equilibria to be completely distinct from renegotiation-proof equilibria, and even to be Pareto inefficient.
    Keywords: Social Games, Matching, Games, Repeated Games, Renegotiation
    Date: 2005–03
  3. By: Navas,Jorge; Kort,Peter M. (Tilburg University, Center for Economic Research)
    Abstract: In this paper we analyze cooperation in R&D in the form of RJVs. We show that the optimal size of an RJV does not only depend on the degree of spillovers, as literature suggests, but also on the cost function of R&D activities. Moreover, the explicit consideration of the fact that R&D projects take time to complete shows that benefits from cooperation in R&D not only allow RJVs to carry out larger R&D projects, but also to reduce the time to completion for projects with a given size and, consequently, to accelerate the acquisition of the benefits associated with the innovation.
    JEL: C73 L13 O31
    Date: 2005
  4. By: Lok,Reinder B.; Romero Morales,Dolores; Vermeulen,Dries (METEOR)
    Abstract: The VCG mechanism has some nice properties if the agents-are-substitutes property holds.For example, for combinatorial auctions the property assures that the VCG mechanism is supported by a pricing equilibrium. The existence of such a pricing equilibrium is a necessary condition for the existence of ascending auctions that are equivalent to the VCG mechanism.Although it is known that the agents-are-substitutes property is important in several settings few problems or subclasses of problems are proven to have the property.In this paper we show for a class of problems that the agents-are-substitutes property holds. Moreover we give two rather natural and small extensions that do not have this property in general.Furthermore we show that in our simple problem class we need the possibility of price discrimination.
    Keywords: operations research and management science;
    Date: 2005
  5. By: Bauke Visser (Faculty of Economics, Erasmus Universiteit Rotterdam); Otto H. Swank (Faculty of Economics, Erasmus Universiteit Rotterdam)
    Abstract: We consider a committee that makes a decision on a project on behalf of 'the public'. Members of the committee agree on the a priori value of the project, and hold additional private information about its consequences. They are experts who care both about the value of the project and about being considered well informed. Before voting on the project, members can exchange their private information simultaneously (so no herding). We show that reputational concerns make the a priori unconventional decision more attractive and lead committees to show a united front. These results hold irrespective of whether information can be manipulated or not. Next, we show that reputational concerns induce members to manipulate information and vote strategically if their preferences differ considerably from those of the member casting the decisive vote. Our last result is that the optimal voting rule balances the quality of information exchange and the alignment of interests of the decisive voter with those of the public.
    Keywords: Committees; communication; reputational concerns; strategic voting
    JEL: D71 D72 D82
    Date: 2005–03–10
  6. By: Johansson-Stenman, Olof (Department of Economics, School of Economics and Commercial Law, Göteborg University); Mahmud, Minhaj (Department of Economics, School of Economics and Commercial Law, Göteborg University); Martinsson, Peter (Department of Economics, School of Economics and Commercial Law, Göteborg University)
    Abstract: Levels of trust are measured by asking standard survey questions on trust and by observing the behaviour in a trust game using a random sample in rural Bangladesh. Follow-up questions and correlations between the sent amount in the trust game and stated expectations reveal that the amount sent in the trust game is a weak measure of trust. The fear of future punishment, either within or after this life, for not being sufficiently generous to others, was the most frequently stated motive behind the respondents’ behaviour, highlighting the potential importance of motives that cannot be inferred directly from people’s behaviour. <p>
    Keywords: Trust; trust game; social capital; field experiment; Bangladesh
    JEL: C93 Z13
    Date: 2005–03–31
  7. By: Johansson-Stenman, Olof (Department of Economics, School of Economics and Commercial Law, Göteborg University); Mahmud, Minhaj (Department of Economics, School of Economics and Commercial Law, Göteborg University); Martinsson, Peter (Department of Economics, School of Economics and Commercial Law, Göteborg University)
    Abstract: Trust is measured using both survey questions and a standard trust experiment using a random sample of individuals in rural Bangladesh. We found no significant effect of the social distance between Hindus and Muslims in the trust experiment in terms of fractions sent or returned, but the responses to the survey questions indicate significant differences: Hindus, the minority, trust other people less in general, and Hindus trust Muslims more than the other way around. <p>
    Keywords: social capital; trust; social distance; religion; trust game; field experiment; Bangladesh
    JEL: C93 Z13
    Date: 2005–03–31
  8. By: George J. Mailath (Department of Economics, University of Pennsylvania); Stephen Morris (Cowles Foundation, Yale University)
    Abstract: Some private-monitoring games, that is, games with no public histories, can have histories that are almost public. These games are the natural result of perturbing public monitoring games towards private monitoring. We explore the extent to which it is possible to coordinate continuation play in such games. It is always possible to coordinate continuation play by requiring behavior to have bounded recall (i.e., there is a bound L such that in any period, the last L signals are sufficient to determine behavior). We show that, in games with general almost-public private monitoring, this is essentially the only behavior that can coordinate continuation play.
    Keywords: repeated games, private monitoring, almost-public monitoring, coordination, bounded recall
    JEL: C72 C73 D82
    Date: 2004–08–20
  9. By: Guofu Tan; Okan Yilankaya
    Abstract: We investigate whether efficient collusive bidding mechanisms are affected by potential information leakage from bidders’ decisions to participate in them within the independent private values setting. We apply the concept of ratifiability introduced by Cramton and Palfrey (1995) and show that when the seller uses a second-price auction with participation costs, the standard efficient cartel mechanisms such as preauction knockouts analyzed in the literature will not be ratified by cartel members. A high-value bidder benefits from vetoing the cartel mechanism since doing so sends a credible signal that she has high value, which in turn discourages other bidders from participating in the seller’s auction.
    Keywords: Auctions, collusion, ratifiability
    JEL: C72 D44 D82
    Date: 2005–02
  10. By: Guofu Tan; Okan Yilankaya
    Abstract: We investigate equilibria of sealed-bid second price auctions with bidder participation costs in the independent private values environment. We focus on equilibria in cutoff strategies (participate and bid the valuation iff it is greater than the cutoff), since if a bidder finds it optimal to participate, she cannot do better than bidding her valuation. When bidders are symmetric, concavity (strict convexity) of the cumulative distribution function from which the valuations are drawn is a sufficient condition for uniqueness (multiplicity) within this class. We also study a special case with asymmetric bidders and show that concavity/convexity plays a similar role.
    Keywords: Second price auctions; participation cost; entry fee; multiplicity of equilibria
    JEL: C62 C72 D44 D82
    Date: 2005–01

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