Essays in Behavioral Decision Theory

This thesis studies decision making under uncertainty and how economic agents respond to information. The classic model of subjective expected utility and Bayesian updating is often at odds with empirical and experimental results; people exhibit systematic biases in information processing and often exhibit aversion to ambiguity. The aim of this work is to develop simple models that capture observed biases and study their economic implications.

In the first chapter I present an axiomatic model of cognitive dissonance, in which an agent's response to information explicitly depends upon past actions. I introduce novel behavioral axioms and derive a representation in which beliefs are directionally updated. The agent twists the information and overweights states in which his past actions provide a higher payoff. I then characterize two special cases of the representation. In the first case, the agent distorts the likelihood ratio of two states by a function of the utility values of the previous action in those states. In the second case, the agent's posterior beliefs are a convex combination of the Bayesian belief and the one which maximizes the conditional value of the previous action. Within the second case a unique parameter captures the agent's sensitivity to dissonance, and I characterize a way to compare sensitivity to dissonance between individuals. Lastly, I develop several simple applications and show that cognitive dissonance contributes to the equity premium and price volatility, asymmetric reaction to news, and belief polarization.

The second chapter characterizes a decision maker with sticky beliefs. That is, a decision maker who does not update enough in response to information, where enough means as a Bayesian decision maker would. This chapter provides axiomatic foundations for sticky beliefs by weakening the standard axioms of dynamic consistency and consequentialism. I derive a representation in which updated beliefs are a convex combination of the prior and the Bayesian posterior. A unique parameter captures the weight on the prior and is interpreted as the agent's measure of belief stickiness or conservatism bias. This parameter is endogenously identified from preferences and is easily elicited from experimental data.

The third chapter deals with updating in the face of ambiguity, using the framework of Gilboa and Schmeidler. There is no consensus on the correct way way to update a set of priors. Current methods either do not allow a decision maker to make an inference about her priors or require an extreme level of inference. In this chapter I propose and axiomatize a general model of updating a set of priors. A decision maker who updates her beliefs in accordance with the model can be thought of as one that chooses a threshold that is used to determine whether a prior is plausible, given some observation. She retains the plausible priors and applies Bayes' rule. This model includes generalized Bayesian updating and maximum likelihood updating as special cases.

Segregation: theoretical approach. an empirical analysis of gender segregation in undergraduate studies at the University of the Basque Country.

The aim of this study is to analyze the gender segregation in undergraduate studies in the University from Basque Country (UPV/EHU). We use data from UPV/EHU for the period 2003-2013. We focus on the period from 2003 to 2013 to analyze the changes in the segregation over ten years. We analyze the tendencies of the men and the women inside undergraduate studies. Undergraduate studies are decomposed into five fields: Legal and social sciences, experimental sciences, engineering, arts and humanities, and health sciences. We draw segregation curves and compute the Gini segregation index within the Lorenz approach. Our results show that the gender segregation in undergraduate studies in the UPV/EHU has decreased from 2003 to 2013.

Evaluación y diseño de un sistema de medida de posición por cable para un mecanismo de cinemática paralela 5R

[ES]El objetivo del presente proyecto es el de diseñar, construir y verificar la validez de un sistema de medida de posición mediante sensores por cable para un mecanismo de cinemática paralela 5R, extensible a cualquier otro mecanismo espacial o planar. En el presente informe el lector encontrará un análisis exhaustivo de los inconvenientes prácticos derivados de la naturaleza del método de monitorización propuesto, el desarrollo completo del modelo matemático obtenido para solventarlos, descripciones y planos sobre el montaje in situ del sistema de medida, resultados empíricos sobre el manipulador paralelo y posibles riesgos para la consecución del proyecto

Wireless optical communication-based spatial pattern

We propose a novel communication technique which utilizes a set of mutually distinguishable optical patterns instead of convergent facula to transmit information. The communication capacity is increased by exploiting the optical spatial bandwidth resources. An optimum detector for this communication is proposed based on maximum-likelihood decision. The fundamental rule of designing signal spatial pattern is formulated from analysis of the probability of error decision. Finally, we present a typical electro-optical system scheme of the proposed communication. (c) 2006 Elsevier GmbH. All rights reserved.

The far-field spatial coherence of Gaussian Schell-model beam in turbulence in terms of position vectors

Spatial coherence properties of beam produced by Gaussian Schell-model source when the beam is propagating through atmosphere have been analyzed in terms of position vectors. New expressions for cross-spectral density of optical field and spectral degree of coherence as well as radiant intensity have been developed. Numerical results illustrated in this paper indicate the coherence degradation suffered from atmospheric turbulence and their directional dependence. (C) 2007 Elsevier GmbH. All rights reserved.

One-shot parallel complex Fourier-domain optical coherence tomography using a spatial carrier frequency

We propose a novel method of one-shot parallel complex Fourier-domain optical coherence tomography using a spatial carrier frequency for full range imaging. The spatial carrier frequency is introduced into the 2-D spectral interferogram in the lateral direction by using a tilted reference wavefront. This spatial-carrier- contained 2-D spectral interferogram is recorded with one shot of a 2-D CCD camera, and is Fourier-transformed in the lateral direction to obtain a 2-D complex spectral interferogram by a spatial-carrier technique. A full-range tomogram is reconstructed from the 2-D complex spectral interferogram. The principle of this method is confirmed by cross-sectional imaging of a glass slip object. (c) 2008 Society of Photo-Optical Instrumentation Engineers.