Elias Tsakas

Elias Tsakas
Maastricht University | UM · Department of Economics

About

50
Publications
1,500
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
191
Citations
Introduction
Skills and Expertise

Publications

Publications (50)
Preprint
Full-text available
It is well known that individual beliefs cannot be identified using traditional choice data, unless we impose the practically restrictive and conceptually awkward assumption that utilities are state-independent. In this paper, we propose a novel methodology that solves this long-standing identification problem in a simple way. Our method relies on...
Preprint
Full-text available
It is well-known that subjective beliefs cannot be identified with traditional choice data unless we impose the strong assumption that preferences are state-independent. This is seen as one of the biggest pitfalls of incentivized belief elicitation. The two common approaches are either to exogenously assume that preferences are state-independent, o...
Article
Full-text available
In the context of Bayesian Persuasion (Kamenica and Gentzkow in Am Econ Rev 101:2590–2615, 2011), typically, a biased Sender designs a signal to influence the binary decision of an unbiased Receiver. Can the Receiver improve her payoffs by adopting a resistance strategy, i.e., by committing into incurring (deterministic or stochastic) costs if she...
Article
We study the effect of noise due to exogenous information distortions in the context of Bayesian persuasion. We first characterize the optimal signal in the prosecutor-judge game from Kamenica and Gentzkow (2011) with a noisy and strongly symmetric communication channel and show that the sender's payoff increases in the number of messages. This imp...
Article
For a fixed game and a type structure that admits a common prior, Action Independence states that the conditional beliefs induced by the common prior do not depend on the player's own strategy. It has been conjectured that Action Independence can be behaviorally characterized by means of a suitable no-betting condition (Dekel & Siniscalchi, 2015),...
Article
Is it possible to guarantee that the mere exposure of a subject to a belief elicitation task will not affect the very same beliefs that we are trying to elicit? In this paper, we introduce mechanisms that make it simultaneously strictly dominant for the subject (a) not to acquire any information that could potentially lead to belief updating as a r...
Article
An investigator is interested in arbitrarily approximating a subject's latent beliefs in obviously dominant strategies (Li, 2017). We prove that Karni's ascending mechanism (Karni, 2009) does not have an obviously dominant strategy. Thus, we introduce the novel descending Karni mechanism which always has obviously dominant strategies. Furthermore,...
Article
Full-text available
In this paper we introduce a novel framework that allows us to model games with players who reason about the opponents’ rationality only in some part of the game tree. We refer to this type of bounded rationality as limited focus. In particular, players try to rationalize their opponents’ moves only at the histories they focus on, i.e., formally, t...
Article
Full-text available
Article
Full-text available
We study common belief of weak-dominance rationality in strategic-form games with ordinal utilities, employing a qualitative model of beliefs. We characterize two standard solution concepts for such games: the Iterated Deletion of Börgers-dominated Strategies (IDBS) and the Iterated Deletion of Inferior Strategy Profiles (IDIP). We do so by imposin...
Article
In this note, we extend Aumann’s agreement theorem to a framework where beliefs are modelled by conditional probability systems à la Battigalli, P., and M. Siniscalchi. 1999. “Hierarchies of Conditional Beliefs and Interactive Epistemology in Dynamic Games.” Journal of Economic Theory 88: 188–230. We prove two independent generalizations of the agr...
Article
Games in which players aim to guess a fraction or multiple p of the average guess are known as guessing games or (p-)beauty contests. In this note, we derive a full characterization of the set of rationalizable strategies and the set of pure strategy Nash equilibria for such games as a function of the parameter p, the number of players and the (dis...
Article
This paper substitutes the standard rationality assumption with approximate rationality in normal form games. We assume that players believe that their opponents might be ε-rational, i.e. willing to settle for a suboptimal choice, and so give up an amount ε of expected utility, in response to the belief they hold. For every player i and every oppon...
Article
Full-text available
In a novel experimental design we study public good games with dynamic interdependencies, where each agent’s wealth at the end of period t serves as her endowment in t+1. In this setting growth and inequality arise endogenously allowing us to address new questions regarding their interplay and effect on cooperation. We find that amounts contributed...
Article
Choice rules based on probability thresholds are common in several disciplines. The most well-known application of such a threshold rule is the standard of reasonable doubt. Accordingly, a rational juror prefers to convict a defendant if and only if the probability that she attaches to the defendant being guilty is above a given threshold. In this...
Article
Full-text available
We introduce a new solution concept, called correlated-belief equilibrium. The difference to Nash equilibrium is that, while each player has correct marginal conjectures about each opponent, it is not necessarily the case that these marginal conjectures are independent. Then, we provide an epistemic foundation and we relate correlated-belief equili...
Article
In an experiment with more than 500 participants we study how past experience of uncertainty (imperfect knowledge of the state space) affects risk preferences. Participants in our experiment choose between a sure outcome and a lottery in 32 periods. All treatments are exactly identical in periods 17-32 but differ in periods 1-16. In the early perio...
Article
In this paper, we introduce a notion of epistemic equivalence between hierarchies of conditional beliefs and hierarchies of lexicographic beliefs, thus extending the standard equivalence results of Halpern (2010) and Brandenburger et al. (2007) to an interactive setting, and we show that there is a Borel surjective function, mapping each conditiona...
Article
We introduce a framework for modeling pairwise interactive beliefs and provide an epistemic foundation for Nash equilibrium in terms of pairwise epistemic conditions locally imposed on only some pairs of players. Our main result considerably weakens not only the standard sufficient conditions by R. J. Aumann and A. Brandenburger [Econometrica 63, N...
Article
In a recent paper, Tsakas [2013 Rational belief hierarchies, Journal of Mathematical Economics, Maastricht University] introduced the notion of rational beliefs. These are Borel probability measures that assign a rational probability to every Borel event. Then, he constructed the corresponding Harsanyi type space model that represents the rational...
Article
In the theory of dynamic games, it is often assumed that players reason about all stages in the game. In this paper we relax this assumption, by allowing players to only reason about some stages in the game .not all. We take the forward induction concept of common strong belief in rationality (Battigalli and Siniscalchi (2002)) and adapt it to this...
Article
We provide a foundation for correlated rationalizability by means of pairwise epistemic conditions imposed only on some pairs of players. Indeed, we show that pairwise mutual belief, for some pairs of players, of (i) the game payoffs, (ii) rationality, and (iii) deeming possible only strategy profiles that receive positive probability by the actual...
Article
We consider agents whose language can only express probabilistic beliefs that attach a rationalnumber to every event. We call these probability measures rational. We introduce the notion of arational belief hierarchy, where the first order beliefs are described by a rational measure overthe fundamental space of uncertainty, the second order beliefs...
Article
In a novel experimental design we study dynamic public good games in which wealth is allowed to accumulate. More precisely each agent's income at the end of a period serves as her endowment in the following period. In this setting growth and inequality arise endogenously allowing us to address new questions regarding their interplay and effect on c...
Article
We provide epistemic conditions for correlated rationalizability, which are considerably weaker than the ones by Zambrano (2008). More specifically, we simultaneously replace mutual knowledge of rationality and mutual knowledge of the event that every player deems possible only strategy proles that belong to the support of her actual conjecture, wi...
Article
In this paper, we consider a finite set of agents with commonly known full-support priors on the fundamental space of uncertainty. Then, we show that if the hierarchies of conditional beliefs á la Battigalli and Siniscalchi (1999) are derived from these priors, then each agent's hierarchy is commonly known, and consequently all types of the same ag...
Article
Full-text available
We show that if an agent reasons according to standard inference rules, the axioms of truth and introspection extend from the set of non-epistemic propositions to the whole set of propositions. This implies that the usual axiomatization of the partitional possibility correspondence, which describes an agent who processes information rationally, is...
Article
In this paper we formalize the notion of lexicographic belief hierarchies in standard partitional models (Aumann, 1976). We introduce the notion of epistemic equivalence between two be-lief space, and show that the state space representation of lexicographic belief hierarchies is equivalent to the usual type-space approach, even when the latter ind...
Article
We introduce and study a unified reasoning process which allows to represent the beliefs of both a fully rational agent and of an unaware one. This reasoning process provides natural properties to introspection and unawareness. The corresponding model for the rational or boundedly rational agents is both easy to describe and to work with, and the a...
Article
The present paper extends the standard model of pairwise communication among Bayesianagents to cases where the structure of the communication protocol is not commonly known.We show that, even under strict conditions on the structure of the protocols and the nature of the transmitted signals, a consensus may never be reached if very little asymmetri...
Article
We study the target projection dynamic, a model of learning in normal form games. The dynamic is given a microeconomic foundation in terms of myopic optimization under control costs due to a certain status-quo bias. We establish a number of desirable properties of the dynamic: existence, uniqueness and continuity of solution trajectories, Nash stat...
Article
In this paper we provide a framework to reason about limited awareness of the action space in finitely repeated games. Our framework is rich enough to capture the full strategic aspect of limited awareness in a dynamic setting, taking into account the possibility that agents might want to reveal or conceal actions to their opponent or that they mig...
Article
Full-text available
In this article we discuss the differences between the average marginal effect and the marginal effect of the average individual in sample selection models, estimated by the Heckman procedure. We show that the bias that emerges as a consequence of interchanging the measures, could be very significant, even in the limit. We suggest a computationally...
Article
We study a model of pairwise communication in a finite population of Bayesian agents. We show that, if the individuals update only according to the signal they actually hear, and they do not take into account all the hypothetical signals they could have received, a consensus is not necessarily reached. We show that a consensus is achieved for a cla...
Article
Full-text available
We study a model of pairwise communication in a finite population of Bayesian agents. We show that, in contrast with claims to the contrary in the existing literature, communication under a fair protocol may not lead to commonly known signals, or even consensus. We prove that, in order for commonly known signals to be achieved, individuals must als...
Article
Full-text available
I consider a gamble where the sum of the distributed payoffs is proportionate to the number of participants. I show that no subset of the population can agree to participate in the bet, if the size of the group is commonly known. Repeated announcements of the number of the participants leads the population to agree not to bet.
Article
Full-text available
We study a model of pairwise communication in a finite population of Bayesian agents. We show that, in contrast with claims to the contrary in the existing literature, communication under a fair protocol may not lead to common knowledge of signals. We prove that commonly known signals are achieved if the individuals convey, in addition to their own...
Article
We study whether rational information processing is testable. Our main result shows that, under positive conditions, negative introspection holds if and only if it holds for primitive propositions. In particular, it is sufficient to test negative introspection on primitive propositions.
Article
Full-text available
In this paper we discuss the differences between the average marginal effect and the marginal effect of the average individual in sample selection models, estimated by Heckman's two step procedure. We show that the bias that emerges as a consequence of interchanging them, could be very significant, even in the limit. We suggest a computationally ch...
Article
We introduce the mixed quantal response equilibrium as an alternative statistical approach to normal form games with random utility function and prove its existence. Then we extend the quantal response equilibrium to payoff functions with disturbances outside the family of admissible distributions. Finally, we define the mixed logit quantal respons...
Article
We conduct an experiment to study how imperfect knowledge of the state space affects subsequent choices under uncertainty with perfect knowledge of the state space. Participants in our experiment choose between a sure outcome and a lottery in 32 periods. All treatments are exactly identical in periods 17 to 32 but differ in periods 1 to 16. In the...

Network

Cited By