Approximate knowledge of rationality and correlated equilibria

We extend Aumann's [3] theorem deriving correlated equilibria as a consequence of common priors and common knowledge of rationality by explicitly allowing for non-rational behavior. We replace the assumption of common knowledge of rationality with a substantially weaker notion, joint p-belief of rationality, where agents believe the other agents are rational with probabilities p = (pi)i2I or more. We show that behavior in this case constitutes a constrained correlated equilibrium of a doubled game satisfying certain p-belief constraints and characterize the topological structure of the resulting set of p-rational outcomes. We establish continuity in the parameters p and show that, for p su ciently close to one, the p-rational outcomes are close to the correlated equilibria and, with high probability, supported on strategies that survive the iterated elimination of strictly dominated strategies. Finally, we extend Aumann and Dreze's [4] theorem on rational expectations of interim types to the broader p-rational belief systems, and also discuss the case of non-common priors.

The role of personal involvement and responsibility in dictatorial allocations: A classroom experiment

Paper was revised on 2009-11-11.-- Published as article in: Rationality and Society (2009), 21(2), 1-24.

Uncertain Information Structures and Backward Induction

In everyday economic interactions, it is not clear whether sequential choices are visible or not to other participants: agents might be deluded about opponents'capacity to acquire,interpret or keep track of data, or might simply unexpectedly forget what they previously observed (but not chose). Following this idea, this paper drops the assumption that the information structure of extensive-form games is commonly known; that is, it introduces uncertainty into players' capacity to observe each others' past choices. Using this approach, our main result provides the following epistemic characterisation: if players (i) are rational,(ii) have strong belief in both opponents' rationality and opponents' capacity to observe others' choices, and (iii) have common belief in both opponents' future rationality and op-ponents' future capacity to observe others' choices, then the backward induction outcome obtains. Consequently, we do not require perfect information, and players observing each others' choices is often irrelevant from a strategic point of view. The analysis extends {from generic games with perfect information to games with not necessarily perfect information{the work by Battigalli and Siniscalchi (2002) and Perea (2014), who provide different sufficient epistemic conditions for the backward induction outcome.

El mapa de Hecateo

[EN] The work of Hecataeus has not been sufficiently recogniced in its scientifical and symbolical importance. The elaboration of the map is in the origin of the theory of proportions, which is essential to the Greek mathematics, origin this that has not been never in mind of the investigators of the Greek mathematics. Its «Genealogies» break the cyclical experience of time of that archaic society. And the scientifical prose, of which he is one of the beginners, opens to new experiences of time, too, introduces a new type of privacy and exploits the potential rationality of the ordinary language, that the sacred poetry obstructed to manifest.

El «Ión»,fundador de la hermenéutica occidental

[ES] En el «Ión» Platón funda la hermenéutica occidental, no la práctica de la exégesis. Para ello debe rechazar el liderazgo de la poesía. Y en un triple frente. Como saber, la poesía no distingue entre significante y significado, y considera la interpretación como un mero descifrado, no como un análisis de la verdad y falsedad del significado. Como discurso legitimador, es una liturgia, no una funcionalización técnica, además de que oculta el conflicto en que toda sociedad consiste. Como competencia interactiva, el poeta no es autónomo, sino alienado, y pone en juego la emotividad, no la racionalidad. Desde este breve diálogo, la filosofía y la literatura se han disociado dramáticamente en la cultura occidental.