Science Illuminating Our Complex World
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IO Reading List
Economics 257 – MGTECON 630 Fall 2020 Professor José Ignacio Cuesta [email protected] Professor Liran Einav [email protected] Professor Paulo Somaini [email protected] Industrial Organization I: Reading List I. Imperfect Competition: Background Bresnahan, Tim “Empirical Studies with Market Power,” Handbook of Industrial Organization, vol. II, chap. 17. Einav, Liran and Jonathan Levin. “Empirical Industrial Organization: A Progress Report,” Journal of Economic Perspectives, 24(2), 145-162 (2010). Tirole, Jean. The Theory of Industrial Organization, Cambridge, MA: MIT Press, 1988. A. Test of Market Power Ashenfelter, O., and D. Sullivan, “Nonparametric Tests of Market Structure: An Application to the Cigarette Industry,” Journal of Industrial Economics 35, 483-498, (1989). Baker, J., and T. Bresnahan, “Estimating the residual demand curve facing a single firm,” International Journal of Industrial Organization 6(3), 283-300, (1988). Corts, K., “Conduct Parameters and the Measurement of Market Power,” Journal of Econometrics 88, 227-225, (1999). Genesove, D. and W. Mullin, “Testing Static Oligopoly Models: Conduct and Cost in the Sugar Industry, 1890-1914,” Rand Journal of Economics 29(2), 355-377, (1989). Stigler, G. “A Theory of Oligopoly,” The Journal of Political Economy, 72(1), 44-61, (1964) Sumner, D., “Measurement of Monopoly Behavior: An Application to the Cigarette Industry,” Journal of Political Economy 89, 1010-1019, (1981). Wolfram, C., “Measurement of Monopoly Behavior: An Application to the Cigarette Industry,” American Economic Review 89($), 805-826, (1999). B. Differentiated Products Anderson, S. P., A. de Palma, and J. F. Thisse, Discrete Choice Theory of Product Differentiation, Chapters 1-5, Cambridge: MIT Press, (1992). Caplin, A., and B. -
The Impotent Fury of William Dembski
THE DESIGN REVOLUTION? How William Dembski Is Dodging Questions About Intelligent Design By Mark Perakh Who is William A. Dembski? We are told that he has PhD degrees in mathematics and philosophy plus more degrees - in theology and what not – a long list of degrees indeed. [1] To acquire all those degrees certainly required an unconventional penchant for getting as many degrees as possible. We all know that degrees alone do not make a person a scientist. Scientific degrees are not like ranks in the military where a general is always above a mere colonel. Degrees are only a formal indicator of a person’s educational status. A scientist’s reputation and authority are based on his degrees only to a negligible extent. What really attests to a person’s status in science is publications in professional journals and anthologies and references to one’s work by colleagues. This is the domain where Dembski has so far remained practically invisible. All his multiple publications have little or nothing to do with science. He is a mathematician who did not prove any theorem and derived not a single formula. When he writes about probability theory or information theory -- on which he is proclaimed to be an expert -- the real experts in these fields (using the words of the prominent mathematician David Wolpert) “squint, furrow one's brows, and then shrug.” [2] When encountering critique of his work, Dembski is selective in choosing when to reply to his critics and when to ignore their critique. His preferred targets for replies are those critics who do not boast comparable long lists of formal credentials – this enables him to contemptuously dismiss the critical comments by pointing to the alleged lack of qualification of his opponents while avoiding answering the essence of their critical remarks. -
The Virtues and Vices of Equilibrium and the Future of Financial Economics
The Virtues and Vices of Equilibrium and the Future of Financial Economics The use of equilibrium models in economics springs from the desire for parsimonious models of economic phenomena that take human reasoning into account. This approach has been the cornerstone of modern economic theory.We explain why this is so, extolling the virtues of equilibrium theory; then we present a critique and describe why this approach is inherently limited, and why economics needs to move in new directions if it is to continue to make progress. We stress that this shouldn’t be a question of dogma, and should be resolved empirically. There are situations where equilibrium models provide useful predictions and there are situations where they can never provide useful predictions. There are also many situations where the jury is still out,i.e.,where so far they fail to provide a good description of the world,but where proper extensions might change this. Our goal is to convince the skeptics that equilibrium models can be useful, but also to make traditional economists more aware of the limitations of equilibrium models.We sketch some alternative approaches and discuss why they should play an important role in future research in economics. © 2008 Wiley Periodicals, Inc. Complexity 14: 11–38, 2009 J. DOYNE FARMER AND JOHN GEANAKOPLOS Key Words: equilibrium; rational expectations; efficiency; arbitrage; bounded ratio- nality; power laws; disequilibrium; zero intelligence; market ecology; agent-based modeling J. Doyne Farmer is affiliated with Santa Fe Institute, Santa Fe, NM 87501 and LUISS Guido Carli, 00198, Roma, Italy 1. INTRODUCTION (e-mail: [email protected]) he concept of equilibrium has dominated economics and finance for at least John Geanakoplos is affiliated with Yale 50 years. -
Curriculum Vitae
Curriculum Vitae September 2018 Ana Fostel Email: [email protected] Department of Economics Old Web Page: www.anafostel.com Monroe Hall, Suite 222 Citizenship: USA. Uruguay. Italy. Charlottesville, VA 22903 Phone: (434) 924 7654 FIELDS OF CONCENTRATION. Financial Economics. International Finance. Economic Theory. Experimental Finance. CURRENT POSITION University of Virginia, Department of Economics, Professor of Economics. Since June 2017. National Bureau of Economic Research. Research Associate. Since June 2017. PREVIOUS POSITIONS University of Virginia, Department of Economics, Associate Professor (with tenure) of Economics. Since August 2015. George Washington University, Department of Economics, Associate Professor (with tenure) of Economics and International Affairs. 2012-2015. George Washington University, Department of Economics, Assistant Professor of Economics and International Affairs. 2005-2011. EDUCATION Ph.D. (with distinction) Department of Economics, Yale University. December 2005. M.Phil. Department of Economics, Yale University. 2002 M.A. Department of Economics, Yale University. 2001. Ph.D. candidate in Mathematics, IMPA Instituto de Matematica Pura e Aplicada. Rio de Janeiro, Brazil. 1999. M.A. Mathematics and Economics, IMPA. Instituto de Matematica Pura e Aplicada. Rio de Janeiro, Brazil. 1998. B.A. Economics, Universidad de la Republica. Montevideo, Uruguay. 1996 RESEARCH Publications Collateral Constraints and the Law of One Price: An Experiment Joint with Marco Cipriani and Daniel Houser. Forthcoming at Journal of Finance. Fiscal Discoveries and Yield Decouplings. Joint with Luis Catão and Romain Ranciere. IMF Review. 2017. Volume 65, Issue 4, pp 704–744. Financial Innovation, Collateral and Investment. Joint with John Geanakoplos. AEJ: Macroeconomics. 2016. Vol. 8(1): 242-284. Leverage and Default in Binomial Economies: AComplete Characterization. -
Multi-Agent Economics and the Emergence of Critical Markets
Multi-agent Economics and the Emergence of Critical Markets Michael S. Harr´e1 1Complex Systems Research Group, Faculty of Engineering and IT, The University of Sydney, Sydney, Australia. Abstract The dual crises of the sub-prime mortgage crisis and the global financial crisis has prompted a call for explanations of non-equilibrium market dynamics. Recently a promising approach has been the use of agent based models (ABMs) to simulate aggregate market dynamics. A key aspect of these models is the endogenous emergence of critical transitions between equilibria, i.e. market collapses, caused by multiple equilibria and changing market parameters. Several research themes have developed microeconomic based models that include multiple equilibria: social decision theory (Brock and Durlauf), quantal response models (McKelvey and Palfrey), and strategic complementarities (Goldstein). A gap that needs to be filled in the literature is a unified analysis of the relationship between these models and how aggregate criticality emerges from the individual agent level. This article reviews the agent-based foundations of markets starting with the individual agent perspective of McFadden and the aggregate perspective of catastrophe theory emphasising connections between the different approaches. It is shown that changes in the uncertainty agents have in the value of their interactions with one another, even if these changes are one-sided, plays a central role in systemic market risks such as market instability and the twin crises effect. These interactions can endogenously cause crises that are an emergent phenomena of markets. 1 Introduction Multi-agent models have grown in popularity [2, 5, 64, 9, 34, 37] as a way in which to simu- late complex market dynamics that might have no closed form solutions. -
Trade with Heterogeneous Prior Beliefs and Asymmetric Information Author(S): Stephen Morris Source: Econometrica, Vol. 62, No. 6 (Nov., 1994), Pp
Trade with Heterogeneous Prior Beliefs and Asymmetric Information Author(s): Stephen Morris Source: Econometrica, Vol. 62, No. 6 (Nov., 1994), pp. 1327-1347 Published by: The Econometric Society Stable URL: http://www.jstor.org/stable/2951751 Accessed: 29-05-2015 02:11 UTC Your use of the JSTOR archive indicates your acceptance of the Terms & Conditions of Use, available at http://www.jstor.org/page/ info/about/policies/terms.jsp JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact [email protected]. The Econometric Society is collaborating with JSTOR to digitize, preserve and extend access to Econometrica. http://www.jstor.org This content downloaded from 128.112.66.66 on Fri, 29 May 2015 02:11:33 UTC All use subject to JSTOR Terms and Conditions Econometrica, Vol. 62, No. 6 (November, 1994), 1327-1347 TRADE WITHHETEROGENEOUS PRIOR BELIEFS AND ASYMMETRICINFORMATION BY STEPHEN MORRIS1 "No trade" theorems have shown that new information will not lead to trade when agents share the same prior beliefs. This paper explores the structure of no trade theorems with heterogeneous prior beliefs. It is shown how different notions of efficiency under asymmetric information-ex ante, interim, ex post-are related to agents' prior beliefs, as well as incentive compatible and public versions of those efficiency concepts. These efficiency results are used to characterize necessary and sufficient conditions on agents' beliefs for no trade theorems in different trading environments. -
Department of Economics Newsletter
DEPARTMENT OF ECONOMICS NEWSLETTER Department of Economics Newsletter May 2015 GENERAL DEPARTMENT NEWS The Economics Department at Johns 2016. Professor Quah is an economic Poster for the Richard Ely Distinguished Hopkins has had another busy year with theorist with many major works to his credit Lecture Series 2014-2015: multiple events and many developmentsMay 20and15 is an outstanding addition to the among the faculty and graduate students. Department. This Newsletter will cover many of them but feel free to keep track of all developments as The Department was well represented at the they happen on the department website, AEA Meetings in January, 2015 in Boston. http://www.econ.jhu.edu/. Among the faculty, Chris Carroll, Olivier Jeanne, Ali Khan, Anton Korinek, Robert We welcomed Assistant Professor Ying Chen Moffitt, Nick Papageorge, and Yuya Sasaki to the Department in September. Ying were on the program. The traditional cocktail specializes in Economic Theory and comes party and reception also drew a number of from Southampton and Arizona State and current and former graduate students and received her Ph.D. from Yale. Ying is faculty. We will be having another in January, teaching graduate and undergraduate 2016 in San Francisco. Mark it on your courses in micro theory. calendars. We look forward to the Spring 2016 Ely We are also happy to report that Dr. Robert Our annual Richard T. Ely Lecture this year Lectures as well, which will be given by Barbera, a graduate alumnus from our was given by John Geanakoplos (photo Professor Robert Porter of Northwestern Department, has continued his stepped up below) from Yale University, who gave four University. -
What Is Important About the No Free Lunch Theorems? 3
What is important about the No Free Lunch theorems? David H. Wolpert Abstract The No Free Lunch theorems prove that under a uniform distribution over induction problems (search problemsor learning problems), all induction algorithms perform equally. As I discuss in this chapter, the importanceofthe theoremsarises by using them to analyze scenarios involving non-uniform distributions, and to compare different algorithms, without any assumption about the distribution over problems at all. In particular, the theorems prove that anti-cross-validation (choosing among a set of candidate algorithms based on which has worst out-of-sample behavior) performs as well as cross-validation, unless one makes an assumption — which has never been formalized — about how the distribution over induction problems, on the one hand,is relatedto the set of algorithmsone is choosingamong using (anti-)cross validation, on the other. In addition, they establish strong caveats concerning the significance of the many results in the literature which establish the strength of a particular algorithm without assuming a particular distribution. They also motivate a “dictionary” between supervised learning and improve blackbox optimization, which allows one to “translate” techniques from supervised learning into the domain of blackbox optimization, thereby strengthening blackbox optimization algorithms. In addition to these topics, I also briefly discuss their implications for philosophy of science. 1 Introduction arXiv:2007.10928v1 [cs.LG] 21 Jul 2020 The first of what are now called the No Free Lunch (NFL) theorems were published in [1]. Soon after publication they were popularizedin [2], building on a preprint ver- sion of [1]. Those first theorems focused on (supervised) machine learning. -
Conference Program
The Third International Conference on Knowledge Discovery and Data Mining August 14–17 1997, Newport Beach, California Sponsored by the American Association for Artificial Intelligence Cosponsored by General Motors Research, The National Institute for Statistical Sciences, and NCR Corporation In cooperation with The American Statistical Association Welcome to KDD-97! KDD-97 Organization General Conference Chair William Eddy, Carnegie Mellon Sally Morton, Rand Corporation University Richard Muntz, University of California Ramasamy Uthurusamy, General Motors Charles Elkan, University of California at at Los Angeles Corporation San Diego Raymond Ng, University of British Usama Fayyad, Microsoft Research Columbia Program Cochairs Ronen Feldman, Bar-Ilan University, Steve Omohundro, NEC Research David Heckerman, Microsoft Research Israel Gregory Piatetsky-Shapiro, Heikki Mannila, University of Helsinki, Jerry Friedman, Stanford University GTE Laboratories Finland Dan Geiger, Technion, Israel Daryl Pregibon, Bell Laboratories Daryl Pregibon, AT&T Laboratories Clark Glymour, Carnegie Mellon Raghu Ramakrishnan, University of University Wisconsin, Madison Publicity Chair Moises Goldszmidt, SRI International Patricia Riddle, Boeing Computer Georges Grinstein, University of Services Paul Stolorz, Jet Propulsion Laboratory Massachusetts, Lowell Ted Senator, NASD Regulation Inc. Tutorial Chair Jiawei Han, Simon Fraser University, Jude Shavlik, University of Wisconsin at Canada Madison Padhraic Smyth, University of California, David Hand, Open University, -
David Wolpert Research Statement
David Wolpert Research Statement Although my degrees were in physics (Princeton, then the Kavli Institute for Theoretical Physics), my interests are far broader. Reflecting this I have worked at the Santa Fe Institute, the Neurosciences Institute at Rockefeller University, Los Alamos’ Center for Nonlinear Studies, TXN (a data-mining startup), and IBM. Currently I am a senior computer scientist at NASA. Reflecting this breadth of my interests, I have published work on the following topics, most of it being on the first four: Multi-agent systems and distributed control Operations research (in particular nonlinear and heuristic optimization) Machine learning Statistics (Bayesian, Sampling theory, and Maxent) Nanotechnology Molecular biology Computation theory Game theory Several branches of mathematics. In the last few years my research focus has been five-fold: 1) PROBABILITY COLLECTIVES: By casting both of them in terms of information theory, game theory and statistical physics are, mathematically, identical. Intuitively, players in a game and their reward functions are identical to particles in a system and their energy functions. This identity allows one to “cut and paste” techniques between these fields, creating a hybrid richer than either by itself. So for example, the proper quantification of the bounded rationality of an agent turns out to be formally identical to a particle’s temperature. As another example, techniques in statistical physics used to analyze systems with varying numbers of particles can be applied to games with varying numbers of agents. Along with the members of my group and collaborators at Oxford, Stanford, Berkeley, and Los Alamos, I have been investigating the extremely rich theory arising from this hybridization. -
REVIEWING the LEVERAGE CYCLE by Ana Fostel and John Geanakoplos September 2013 COWLES FOUNDATION DISCUSSION PAPER NO. 1918 COWLE
REVIEWING THE LEVERAGE CYCLE By Ana Fostel and John Geanakoplos September 2013 COWLES FOUNDATION DISCUSSION PAPER NO. 1918 COWLES FOUNDATION FOR RESEARCH IN ECONOMICS YALE UNIVERSITY Box 208281 New Haven, Connecticut 06520-8281 http://cowles.econ.yale.edu/ Reviewing the Leverage Cycle∗ Ana Fostel † John Geanakoplos ‡ September, 2013 Abstract We review the theory of leverage developed in collateral equilibrium models with incomplete markets. We explain how leverage tends to boost asset prices, and create bubbles. We show how leverage can be endogenously determined in equilibrium, and how it depends on volatility. We describe the dynamic feedback properties of leverage, volatility, and asset prices, in what we call the Leverage Cycle. We also describe some cross-sectional implications of multiple leverage cycles, including contagion, flight to collateral, and swings in the issuance volume of the highest quality debt. We explain the differences between the leverage cycle and the credit cycle literature. Finally, we describe an agent based model of the leverage cycle in which asset prices display clustered volatility and fat tails even though all the shocks are essentially Gaussian. Keywords: Leverage, Leverage Cycle, Volatility, Collateral Equilibrium, Collateral Value, Liquidity Wedge, Flight to Collateral, Contagion, Adverse selection, Agent Based Models. 1 Introduction Before the great financial crisis of 2007-09, mainstream macroeconomics regarded interest rates and technology shocks as the most important drivers of economic ac- tivity and asset prices. The Federal Reserve, charged with maintaining stable prices ∗Paper is submitted to the Annual Review of Economics. DOI for the paper is 10.1146/annurev- economics-080213-041426. †George Washington University, Washington, DC ‡Yale University, New Haven, CT, Santa Fe Institute, Ellington Capital Management. -
Greek Debt and American Debt: Graduation Speech at the University of Athens Economics and Business School
GREEK DEBT AND AMERICAN DEBT: GRADUATION SPEECH AT THE UNIVERSITY OF ATHENS ECONOMICS AND BUSINESS SCHOOL By John Geanakoplos November 2011 COWLES FOUNDATION DISCUSSION PAPER NO. 1837 COWLES FOUNDATION FOR RESEARCH IN ECONOMICS YALE UNIVERSITY Box 208281 New Haven, Connecticut 06520-8281 http://cowles.econ.yale.edu/ Greek Debt and American Debt Graduation Speech at the University of Athens Economics and Business School June 2011 John Geanakoplos Abstract: This is the graduation speech I gave on receiving an honorary doctorate at the University of Athens Economics and Business School. I talk about my Greek family, about how I got interested in economics, and then how in the 1990s I came to think about default, collateral, and leverage as the central features of the financial/macro economy, despite their complete absence (even now) from any textbooks. Finally I suggest that the Greek debt problem, and on a bigger scale, the American debt problem, can only be cured when lenders are prodded to forgive. That would be better for the borrowers but also for the lenders. Key Words: Greek, parents, mathematical economics, Yale, mortgage, collateral, securitization, leverage, foreclosure, forgive, principal. JEL: D52, D53, E444, G01, G10, G12 1 Greek Debt and American Debt Graduation Speech at the University of Athens Economics and Business School June 2011 I am very honored to receive this honorary PHD here in Greece. Were they still alive, my parents would have been very proud, just like your parents are today. Though my parents were born in the United States, they both grew up speaking Greek before they spoke English.