The Evolutionary Stability of Optimism, Pessimism and Complete Ignorance

We provide an evolutionary foundation to evidence that in some situations humans maintain optimistic or pessimistic attitudes towards uncertainty and are ignorant to relevant aspects of the environment. Players in strategic games face Knightian uncertainty about opponents’ actions and maximize individually their Choquet expected utility. Our Choquet expected utility model allows for both an optimistic or pessimistic attitude towards uncertainty as well as ignorance to strategic dependencies. An optimist (resp. pessimist) overweights good (resp. bad) outcomes. A complete ignorant never reacts to opponents’ change of actions. With qualifications we show that optimistic (resp. pessimistic) complete ignorance is evolutionary stable / yields a strategic advantage in submodular (resp. supermodular) games with aggregate externalities. Moreover, this evolutionary stable preference leads to Walrasian behavior in those classes of games

Bayesian Quadratic Network Game Filters

A repeated network game where agents have quadratic utilities that depend on information externalities -- an unknown underlying state -- as well as payoff externalities -- the actions of all other agents in the network -- is considered. Agents play Bayesian Nash Equilibrium strategies with respect to their beliefs on the state of the world and the actions of all other nodes in the network. These beliefs are refined over subsequent stages based on the observed actions of neighboring peers. This paper introduces the Quadratic Network Game (QNG) filter that agents can run locally to update their beliefs, select corresponding optimal actions, and eventually learn a sufficient statistic of the network's state. The QNG filter is demonstrated on a Cournot market competition game and a coordination game to implement navigation of an autonomous team

Does it pay to play? How bargaining shapes donor participation in the funding of environmental protection

Multilateral funding for global environmental protection, such as biodiversity conservation, requires donor participation. When are donors willing to participate? We examine a game-theoretic model of multilateral funding for environmental projects in developing countries. Donors must first decide whether to participate in a multilateral institution. They do so in anticipation of a bargaining outcome that depends on their participation decisions. The multilateral institution then bargains with a recipient over the distribution of gains from project implementation. We find that the donors' and the recipient's vulnerability to negative environmental externalities have diverging effects on their participation behavior. As donors' vulnerability to negative externalities increases, their bargaining power decreases and fewer donors participate. But as the recipient's vulnerability increases, more donors participate because their bargaining power grows. These findings can illuminate bargaining over multilateral climate finance and inform the design of international institutions

A supply side story for a threshold model: Endogenous growth of the free and open source community

The study of social institutions producing and disseminating knowledge has mainly concentrated on two main concepts: Science and Technology. This paper examines a recent institutional form that seems not to resemble either of the other two; that is, knowledge-intensive communities, where individuals freely exchange knowledge through information and communication technology. Using free and open source software as an example, we develop a model where this phenomenon is confronted with Technology with respect to its ability to attract researchers.