About Me

I am a PhD Candidate in the Department of Economics at the University of California, Berkeley. My research interests are in the methodology of economics, with a special focus on revealed preference theory. I am also interested in applications of game theory and mechanism design. During my PhD I have worked under the supervision of Shachar Kariv.

Please do not hesitate to contact me, especially if you have comments or questions about my research (or yours!). My email is cugarte@berkeley.edu

I will be on the job market during the 2021/22 academic year.

Research Projects

Preference Recoverability from Inconsistent Choices (Job Market Paper)

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We study the problem of recovering preferences from choices that violate the Generalized Axiom of Revealed Preferences (GARP). The underlying model is that failure of GARP arises because the agent has an imperfect implementation of her preferences. Existing methods to recover preferences rely on intuitive motivations that specify the structure's imperfect implementations. Instead, we take an agnostic approach, which allows us to propose the first statistically consistent estimator. The main assumption is that revealed preferences, the classical tool to analyze choices, are more likely correct than not and hence a trustworthy source of information. For finite data, the set of possible estimators is characterized by the directly revealed preferences that are interpreted as incorrect. Besides consistency, our estimator also satisfies partial efficiency, a standard requirement in the literature. We apply our estimator to laboratory data and compare it with the one derived from the Varian Index. Our estimator presents a stronger correlation between accuracy and its measure of distance from GARP; it is also significantly faster and more feasible to implement for subjects with many inconsistencies. Finally, we show how to extend our method to a vast class of choice problems beyond the classical consumer setting.

The generality of the Strong Axiom

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A widespread assumption in economics is that consumers have strictly convex preferences and hence a (single-valued) demand function. When choices are rationalizable strict convexity can be tested by the Strong Axiom of Revealed Preferences (SARP). We extend this test to non-rationalizable choices by recovering preferences under partial efficiency. Our main result shows that for non-rationalizable choices strict convexity cannot be falsified. Hence a demand function is falsifiable only if choices are rationalizable and fail SARP, which we do not observe in laboratory choice data. Our results suggest that assuming strict convexity does not imply a substantial cost.

On the incentive compatibility of the Bitcoin protocol

with Marcelo Arenas and Martín Ugarte

[Draft coming soon]

Contrary to traditional payment systems, the Bitcoin protocol does not rely on a trusted central authority to maintain a ledger of transactions. Instead, it relies on a protocol based on a free-entry market, known as the Bitcoin protocol, and proposed by Nakamoto (2008). In this protocol miners compete for appending blocks of transactions to the ledger, generating a tree-like data structure in which the one branch, called the blockchain, is the set of valid transactions (the actual ledger). For users to consider Bitcoin a secure payment system, they need to know that once a transaction has been validated (added to the blockchain) it has a negligible probability of being reversed.

This work models the Bitcoin protocol as a game of incomplete information. We show that previous studies of the incentives behind the protocol consider oversimplified models, either (1) ignoring important technical aspects of the protocol or (2) analyzing the strategy of a single player without considering the equilibria of the game. We apply our model to show that the original claim made by Nakamoto about the security of the protocol can be sustained as an equilibrium of the game.

Teaching Experience

Teaching Assistant @ University of California, Berkeley

- Graduate Game Theory (prof. Shachar Kariv), Spring 2020 and 2021

                Notes

- Graduate Choice Theory (prof. David Ahn), Fall 2017, 2018, and 2019

- Graduate Mechanism Design (prof. Haluk Ergin), Spring 2018

- Undergraduate Game Theory (prof. Shachar Kariv), Fall 2020

- Undergraduate Macroeconomic Theory (prof. Yuriy Gorodnichenko), Spring 2019

- Undergraduate Microeconomic Analysis (prof. Scott Carson), Summer 2019 and 2020

Lecturer @ PPIA Junior Summer Institute - University of California, Berkeley

- Introduction to Economics, Summer 2018

Lecturer @ Pontificia Universidad Católica de Chile

- Introduction to Economics, Spring 2011 to Spring 2014

Lecturer @ Universidad de Los Andes, Chile

- Advanced Micreonomics, Spring 2014

- Intermediate Micreonomics, Fall 2013 and Spring 2014

- Advanced Macreonomics, Fall 2013

- Intermediate Macreonomics, Fall 2013 and Spring 2014

Teaching Assistant @ Pontificia Universidad Católica de Chile

- Graduate Courses (2008-2009): Microeconomic Theory, Econometric Theory

- Undergraduate Courses (2006-2009): Algebra, Integral Calculus, Principles of Economics, Intermediate Microeconomics, Intermediate Macroeconomics, Econometrics, Industrial Organization, Economics of Poverty.

CV

You can download my CV here.