GOTTARDI, Piero, TALLON, Jean Marc, GHIRARDATO, Paolo
This paper studies the costs and benefits of delegating decisions to superiorly informed agents relative to the use of rigid, non discretionary contracts. Delegation grants some flexibility in the...
Gottardi, Piero, Tallon, Jean-Marc, Ghirardato, Paolo
This paper studies the costs and benefits of delegating decisions to superiorly informed agents relative to the use of rigid, non discretionary contracts. Delegation grants some flexibility in the...
Gottardi, Piero, Tallon, Jean-Marc, Ghirardato, Paolo
This paper studies the costs and benefits of delegating decisions to superiorly informed agents relative to the use of rigid, non discretionary contracts. Delegation grants some flexibility in the...
Printed in U.S.A. RISK, AMBIGUITY, AND THE SEPARATION OF UTILITY AND BELIEFS (2008)
Paolo Ghirardato, Massimo Marinacci
We introduce a general model of static choice under uncertainty, arguably the weakest model achieving a separation of cardinal utility and a unique representation of beliefs. Most of the nonexpected...
Foundations of Bayesian Theory (2008)
Edi Karni, Jacques Drèze, Peter Fishburn, Paolo Ghirardato
This paper states necessary and sufficient conditions for the existence, uniqueness, and updating according to Bayes ’ rule, of subjective probabilities representing individuals ’ beliefs. The...
Unanimous subjective probabilities (2008)
Border, Kim C., Ghirardato, Paolo, Segal, Uzi
This note shows that if the space of events is sufficiently rich and the subjective probability function of each individual is non-atomic, then there is a σ-algebra of events over which everyone...
Paolo Ghirardato, Paolo Ghirardato, Paolo Ghirardato, Fabio Maccheroni, Fabio Maccheroni, ...
The objective of this paper is to show how ambiguity, and a decision maker (DM)’s response to it, can be modelled formally in the context of a very general decision model. In the first part of the...
Paolo Ghirardato, Paolo Ghirardato, Paolo Ghirardato, Michel Le Breton, Michel Le Breton, ...
We provide a characterization of the consequences of the assumption that a decision maker with a given utility function is Choquet rational: She maximizes expected utility, but possibly with respect...
Belief Dependent Utilities, Aversion to State-Uncertainty and Asset Prices (2007)
John Y. Campbell, Micaela Della Torre, Paolo Ghirardato, Lars P. Hansen, Nick Polson, ...
This paper reinterprets standard axioms in choice theory to introduce the concepts of “belief dependent ” utility functions and aversion to “state-uncertainty, ” and it shows that this type...
in the 21st Seminar of the European Group of Risk and Insurance Economists for stimulating (2007)
Peter Klibano, Michele Cohen, Edi Karni, Paolo Ghirardato, Other Participants
discussions that motivated me to begin this work. Eddie Dekel and Massimo Marinacci provided very helpful comments on a preliminary draft. All errors are my own. Uncertainty aversion is often...
Maxmin Expected Utility, Range Convexity (2007)
Paolo Ghirardato, Paolo Ghirardato, Paolo Ghirardato, Massimo Marinacci, Massimo Marinacci, Massimo Marinacci
We show that range convexity of beliefs, a ‘technical ’ condition that appears naturally in axiomatizations of preferences in a Savage-like framework, imposes some unexpected restrictions when...
Ambiguity Made Precise: A Comparative (2007)
Paolo Ghirardato, Paolo Ghirardato, Paolo Ghirardato, Massimo Marinacci, Massimo Marinacci, Massimo Marinacci
Foundation
A Subjective Spin on Roulette Wheels ∗ (2007)
Paolo Ghirardato, Paolo Ghirardato, Paolo Ghirardato, Fabio Maccheroni, Fabio Maccheroni, ...
We provide a behavioral foundation to the notion of ‘mixture ’ of acts, which is used to great advantage in the decision setting introduced by Anscombe and Aumann [1]. Our construction allows one...
The Impact of Ambiguity On Prices And Allocations In Competitive Financial Markets (2007)
Bossaerts, P., Ghirardato, Paolo, Guarnaschelli, Serena, Zame, W. R.
Objective Subjective Probabilities (2005)
Border, Kim C., Ghirardato, Paolo, Segal, Uzi
This note shows that if the space of events is sufficiently rich and the subjective probability function of each individual is non-atomic, then there is a sigma-algebra of events over which everyone...
Paolo Ghirardato, Fabio Maccheroni, Massimo Marinacci
We dedicate this paper—an extended version of which was previously circulated with the title ‘‘Ambiguity
A brain imaging study of the choice procedure (2002)
Rustichini, Aldo, Dickhaut, John, Ghirardato, Paolo, Smith, Kip, Pardo, Jose
We study the behavior of subjects facing choices between certain, risky, partially ambiguous, and ambiguous lotteries in an experimentally controlled environment. Our observations are subjects'...
Paolo Ghirardato, Paolo Ghirardato, Jonathan N. Katz, Jonathan N. Katz
In this paper we show how to incorporate quality of information into a model of voting behavior. We do so in the context of the turnout decision of instrumentally rational voters who differ in their...
Ambiguity made precise: A comparative foundation (2002)
Paolo Ghirardato, Massimo Marinacci
Simon Grant and Peter Wakker for helpful comments and discussions. Our greatest debt of gratitude is however to Larry Epstein, who sparked our interest on this subject with his paper (Epstein 1997),...
Paolo Ghirardato, Massimo Marinacci, Paolo Ghirardato, Massimo Marinacci
We introduce a general model of static choice under uncertainty, arguably the weakest model achieving a separation of cardinal utility and a unique representation of beliefs. Most of the non-expected...
Risk, ambiguity, and the separation of utility and beliefs (2001)
Paolo Ghirardato, Paolo Ghirardato, Paolo Ghirardato, Massimo Marinacci, Massimo Marinacci, Massimo Marinacci
We introduce and characterize axiomatically a general model of static choice under uncertainty, which is possibly the weakest model in which a separation of cardinal utility and a representation of...
Indecision Theory: Explaining Selective Abstention in Multiple Elections (2000)
Paolo Ghirardato, Paolo Ghirardato, Jonathan N. Katz, Jonathan N. Katz
We present a new model of voting which explains the so-called “roll-off” phenomenon: Selective abstention in multiple elections. We first characterize when a Bayesian voter prefers to abstain,...
Indecision Theory: Explaining Selective Abstention in Multiple Elections (2000)
Paolo Ghirardato, Paolo Ghirardato, Jonathan N. Katz, Jonathan N. Katz
We present a new model of voting which explains the so-called “roll-off” phenomenon: Selective abstention in multiple elections. We first characterize when a Bayesian voter prefers to abstain,...
Indecision Theory: Explaining Selective Abstention in Multiple Elections (2000)
Paolo Ghirardato, Jonathan N. Katz
We address the so-called “roll-off ” phenomenon: Selective abstention in multiple elections. We present a discuss a novel model of decision making by voters that explains this as a result of...
Indecision Theory: An Informational Model of Roll-Off (1997)
Paolo Ghirardato, Jonathan N. Katz
We address the so-called "roll-off" phenomenon: Selective abstention in multiple elections. We present a discuss a novel model of decision making by voters that explains this as a result of...
A model of non-additive uncertainty and its applications to economics / (1995)
Thesis (Ph. D. in Economics)--University of California, Berkeley, May 1995.
article no. ET962241 On Independence for Non-Additive Measures, with a Fubini Theorem (1995)
An important technical question arising in economic and financial applications of decision models with non-additive beliefs is how to define stochastic independence. In fact the straightforward...
A brain imaging study of the choice procedure
Rustichini, Aldo, Dickhaut, John, Ghirardato, Paolo, Smith, Kip, Pardo, Jose V.
Objective subjective probabilities
Border, Kim C., Ghirardato, Paolo, Segal, Uzi
subjective probability, objective probability, Dubins-Spanier theorem, fair division
Risk, Ambigity and the Separation of Utility and Beliefs
Ghirardato, Paolo, Marinacci, Massimo
We introduce and characterize axiomatically a general model of static choice under uncertainty, which is possibly the weakest model in which a separation of cardinal utility and a representation of...
A Subjective Spin on Roulette Wheels
Ghirardato, Paolo, Maccheroni, Fabio, Marinacci, Massimo, Siniscalchi, Marciano
Objective Subjective Probabilities
Kim C. Border, Paolo Ghirardato, Uzi Segal
This note shows that if the space of events is sufficiently rich and the subjective probability function of each individual is non-atomic, then there is a sigma-algebra of events over which everyone...
Ambiguity in Asset Markets: Theory and Experiment
Peter Bossaerts, Serena Guarnaschelli, Paolo Ghirardato, William Zame
This paper studies the impact of ambiguity and ambiguity aversion on equilibrium asset prices and portfolio holdings in competitive nancial markets. It argues that attitudes toward ambiguity are...
Indecision Theory: Weight of Evidence and Voting Behavior
PAOLO GHIRARDATO, JONATHAN N. KATZ
In this paper, we show how to incorporate weight of evidence, or ambiguity, into a model of voting behavior. We do so in the context of the turnout decision of instrumentally rational voters who...
Risk, Ambiguity and the Separation of Utility and Beliefs
Paolo Ghirardato, Massimo Marinacci
The theory of subjective expected utility (SEU) has been extended in many recent works, allowing ambiguity to matter for choice. However, a fully satisfactory and general notion of ambiguity...
A subjective spin on roulette wheels.
Paolo Ghirardato, Fabio Maccheroni, Massimo Marinacci, Marciano Siniscalchi
We provide a behavioral foundation to the notion of ‘mixture’ of acts, which is used to great advantage in he decision setting introduced by Anscombe and Aumann. Our construction allows one to...
Ambiguity from the Differential Viewpoint.
Paolo Ghirardato, Fabio Maccheroni, Massimo Marinacci
The objective of this paper is to show how ambiguity, and a decision maker (DM)'s response to it, can be modelled formally in the context of a very general decision model. In the first part of the...
Indecision Theory: Explaining Selective Abstention in Multiple Elections
Ghirardato, Paolo, Katz, Jonathan N.
We present a new model of voting which explains the so-called "roll-off" phenomenon: Selective abstention in multiple elections. We first characterize when a Bayesian voter prefers to abstain, and...
Range Convexity and Ambiguity Averse Preferences
Ghirardato, Paolo, Marinacci, Massimo
We show that range convexity of beliefs, a 'technical' condition that appears naturally in axiomatizations of preferences in a Savage-like framework, imposes some unexpected restrictions when...
Ambiguity Made Precise: A Comparative Foundation and Some Implications
Ghirardato, Paolo, Marinacci, M.
The theory of subjective expected utility (SEU) has been recently extended to allow ambiguity to matter for choice. We propose a notion of absolute ambiguity aversion by building on a notion of...
Revealed Ambiguity and Its Consequences: Updating
Paolo Ghirardato, Fabio Maccheroni, Massimo Marinacci
We study the updating of beliefs under ambiguity for invariant biseparable preferences. In particular, we show that a natural form of dynamic consistency characterizes the Bayesian updating of these...
A Subjective Spin on Roulette Wheels
Paolo Ghirardato, Fabio Maccheroni, Massimo Marinacci, Marciano Siniscalchi
We provide a simple behavioral definition of 'subjective mixture' of acts for a large class of (not necessarily expected-utility) preferences. Subjective mixtures enjoy the same algebraic properties...
Risk, ambiguity, and the separation of utility and beliefs.
Massimo Marinacci, Paolo Ghirardato
We introduce a general model of static choice under uncertainty, arguably the weakest model achieving a separation of cardinal utility and a unique representation of beliefs. Most of the non-expected...
Certainty Independence and the Separation of Utility and Beliefs.
Paolo Ghirardato, Fabio Maccheroni, Massimo Marinacci
Economists often operate under an implicit assumption that the tastes of a decision maker are constant, while his beliefs change with the availability of new information. It is therefore customary to...
A brain imaging study of the choice procedure
Aldo Rustichini, John Dickhaut, Paolo Ghirardato, Kip Smith, Jose V. Pardo
Paolo Ghirardato, Massimo Marinacci
We focus on the following uniqueness property of expected utility preferences: Agreement of two preferences on one interior indifference class implies their equality. We show that, besides expected...
research articles : Coping with ignorance: unforeseen contingencies and non-additive uncertainty
In real-life decision problems, decision makers are never provided with the necessary background structure: the set of states of the world, the outcome space, the set of actions. They have to devise...
research articles : Revisiting Savage in a conditional world
I present an axiomatization of subjective expected utility and Bayesian updating in a conditional decision problem. This result improves our understanding of the Bayesian standard from two...
Unanimous subjective probabilities
Kim Border, Paolo Ghirardato, Uzi Segal
Agreement, Subjective probability, Objective probability, C69, D79, D89,
GHIRARDATO, Paolo, LE BRETON, Michel
We provide a characterization of the consequences of the assumption that a decision maker with a given utility function is Choquet rational: She maximizes expected utility, but possibly with respect...
Piero Gottardi, Jean Marc Tallon, Paolo Ghirardato
This paper studies the costs and benefits of delegating decisions to superiorly informed agents relative to the use of rigid, non discretionary contracts. Delegation grants some flexibility in the...
Piero Gottardi, Jean-Marc Tallon, Paolo Ghirardato
This paper studies the costs and benefits of delegating decisions to superiorly informed agents relative to the use of rigid, non discretionary contracts. Delegation grants some flexibility in the...
Piero Gottardi, Jean-Marc Tallon, Paolo Ghirardato
This paper studies the costs and benefits of delegating decisions to superiorly informed agents relative to the use of rigid, non discretionary contracts. Delegation grants some flexibility in the...