(Fonte: Lattes)
Projetos de Pesquisa
Unidades Organizacionais
Resumo profissional
Área de pesquisa
Nome para créditos
Faro, José Heleno

Resultados de Busca

Agora exibindo 1 - 10 de 24
  • Artigo Científico
    On the confidence preferences model
    (2012) Chateauneuf, Alain; Faro, José Heleno
    In this paper we study the model of decision under uncertainty consistent with confidence preferences. In that model, a decision maker held beliefs represented by a fuzzy set of priors and tastes captured by a standard affine utility index on consequences. First, we find some interesting properties concerning the well-known maxmin expected utility model, taking into account the point of view of the confidence preferences model. Further, we provide new examples of preferences that capture ambiguity-averse attitudes weaker than ambiguity attitudes featured by maxmin expected utility theory. Finally, we discuss the axiomatic foundations for the confidence preferences model with optimistic behavior.
  • Artigo Científico
    Independence and variational bewley preferences: a note
    (2020) Bastianello, Lorenzo; Faro, José Heleno; Teles, Flávia
    This note studies some alternatives and weak versions of the Independence axiom in a decision theoretic framework under uncertainty. We propose a characterization of this axiom using a property called Weight Independence. Moreover we study how the Independence axiom is related with the Variational Bewley model of Faro [2015]. We show that Variational Bewley preferences satisfy a weaker form of independence called Independence for Constant Weights. This topic gives us the opportunity to discuss the pioneeristic contributions of David Schmeidler on the weakening of the Independence axiom.
  • Trabalho de Evento
    Dynamic bbjective and subjective rationality
    (2014) Faro, José Heleno; Lefort, Jean Philippe
    The objective and subjective rationality model characterizes decision makers (DMs) by two preference relations over uncertain acts and provides a dual perspective on rationality. The Örst preference reáects choices that are rational in an objective sense and the second one expresses choices labeled as subjectively rational. While an objective ranking means that the DM can convince others of the correctness of making them, in a sub jective choice the DM cannot be convinced of the incorrectness of making them. Objective and subjective preferences are represented, respectively, by Bewleyís unanimity rule and a maxmin expected utility, both repre sentations holding the same set of multiple priors. We propose and axiomatize a dynamic model for the objective and subjective rationality theory. The static model speciÖes some set of prior probabilities, which should be then updated in the light of new and rele vant information. We provide two new axioms on the interplay of uncon ditional objective relations and conditional subjective preferences. Such axioms ensure that a conditional subjective relation is also a maxmin ex pected utility preference and the corresponding set of priors is generated by the full Bayesian updating rule. Our main result thus provides a foun dation for sequentially consistent maxmin subjective preferences, where the prior sets are updated according to the prior-by-prior Bayesí rule. Finally, we study the dynamics of objective preferences and its relations with our main result.
  • Artigo Científico
    Pricing rules and arrow – debreu ambiguous valuation
    (2012) Araujo, Aloisio; Chateauneuf, Alain; Faro, José Heleno
    This paper considers pricing rules of single-period securities markets with finitely many states. Our main result characterizes those pricing rules C that are super-replication prices of a frictionless and arbitrage-free incomplete asset structure with a bond. This characterization relies on the equivalence between the sets of frictionless securities and securities priced by C. The former captures securities without bid-ask spreads, while the second captures the class of securities where, if some of its delivers is replaced by a higher payoff, then the resulting security is characterized by a higher value priced by C. We also analyze the special case of pricing rules associated with securities markets admitting a structure of basic assets paying one in some event and nothing otherwise. In this case, we show that the pricing rule can be characterized in terms of capacities. This Arrow–Debreu ambiguous state price can be viewed as a generalization for incomplete markets of Arrow–Debreu state price valuation. Also, some interesting cases are given by pricing rules determined by an integral w.r.t. a risk-neutral capacity. For instance, incomplete markets of Arrow securities and a bond are revealed by a Choquet integral w.r.t. a special risk-neutral capacity.
  • Artigo Científico
    Ambiguity aversion in the long run: “To disagree, we must also agree”
    (2016) Araujo, Aloisio; Silva, Pietro da; Faro, José Heleno
  • Livro
    Introdução à Teoria da Escolha
    (2005) Faro, José Heleno; Castro, Luciano Irineu de
    Esta monografia está dividida em quatro partes: escolha sob certeza, escolha sob risco e incerteza, escolha sob ambigüidade e escolha social. Antes de descrever o que contém cada uma das partes, vamos esclarecer a distinção entre risco, incerteza e ambigüidade.
  • Artigo Científico
    Variational bewley preferences
    (2015) Faro, José Heleno
  • Artigo Científico
    Dynamically consistent objective and subjective rationality
    (2022) Faro, José Heleno; Bastianello, Lorenzo; Santos, Ana
  • Artigo Científico
    Dynamic objective and subjective rationality
    (2019) Faro, José Heleno; Lefort, Jean Philippe
    We characterize prior-by-prior Bayesian updating using a model proposed by Gilboa, Maccheroni, Marinacci, and Schmeidler (2010) that jointly considers objective and subjective rationality. These rationality concepts are subject to the Be wley unanimity rule and maxmin expected utility, respectively, with a common set of priors and the same utility over consequences. We use this setup with two preference relations to develop a novel rationale for full Bayesian updating of maxmin expected utility preferences.
  • Artigo Científico
    Cobb-Douglas preferences under uncertainty
    (2013) Faro, José Heleno
    This paper axiomatizes Cobb-Douglas preferences under uncertainty. First, we extend the original Trockel (Econ Lett 30:7–10, 1989)’s axiomatic foundation to a general state space framework based on the Strong Homotheticity Axiom, obtaining also the incomplete case a la Bewley (Decis Econ Financ 25:79–110, 2002). We show that this key axiom for the Cobb-Douglas expected utility specification is refuted by Ellsberg’s uncertainty aversion behavioral pattern. Our main result provides a set of meaningful axioms characterizing Cobb-Douglas min-expected utility preferences, an important class of uncertainty averse preferences for studying the consequences of ambiguity in finance and other fields. Finally, we present briefly how to obtain more general representations like the variational case.