Andreu Mas-Colell (; born 29 June 1944) is an economist, an expert in microeconomics and a prominent mathematical economist. He is the founder of the Barcelona Graduate School of Economics and a professor in the department of economics at Pompeu Fabra University in Barcelona, Catalonia, Spain. He has also served several times in the cabinet of the Catalan government. Summarizing his and others' research in general equilibrium theory, his monograph gave a thorough exposition of research using differential topology. His textbook on microeconomics, co-authored with Michael Whinston and Jerry Green, is the most used graduate microeconomics textbook in the world.
In June 2021, Spain’s Court of Auditors found that he was among those responsible for government expenditure on the unconstitutional 2017 Catalan independence referendum, and announced its intention to fine him millions of euros; one member of the court dissented, and an outcry from economists followed.
Biography
A native of Barcelona, Mas-Colell completed his undergraduate studies at the University of Barcelona, earning a degree in economics in 1966. He moved to the University of Minnesota for his graduate studies, and completed his Ph.D. in 1972 under the supervision of Marcel Richter. He took a faculty position in mathematics and economics at the University of California, Berkeley, becoming a full professor in 1979. In 1981, he moved to Harvard University, and in 1988 he became the Louis Berkman Professor of Economics at Harvard. In 1995 he moved to Pompeu Fabra to lead the Department of Economics and Business. He was editor-in-chief of the Journal of Mathematical Economics from 1985 to 1989, and of Econometrica from 1988 to 1998. He was president of the Econometric Society in 1993 and of the European Economic Association in 2006.
In public service, Mas-Colell was the Commissioner for Universities and Research of the Generalitat of Catalonia in 1999–2000. While Minister of Universities, Research and the Information Society for the Generalitat from 2000 to 2003, Mas-Colell implemented a research institution called Catalan Institution for Research and Advanced Studies (ICREA) to attract top-notch scientists in all fields of knowledge, from philosophers to astrophysicists, to perform their research in 50 different host institutions in Catalonia. Mas-Colell served the Secretary General of the European Research Council from 2009 to 2010. In the Catalonia Government from 2010-2016, presided by Artur Mas, he was appointed as the Councillor for Economy and Knowledge, being responsible for the government's budget, economic policy, and research policy.
Spain’s Court of Auditors in June 2021 held Mas-Colell and several former colleagues in the Catalan government responsible for the mismanagement of €4.8m in support of Catalan independence. Paul Romer, a Nobel prizewinner in economics, said that the procedure appeared to be ‘not justice but politics by other means.’ One member of the tribunal voted against the decision.
Research
Mas-Colell's research has ranged broadly over mathematical economics. In particular, he has been associated with a revival of the use of differential calculus (in the form of "global analysis") at the highest levels of mathematical economics. Following John von Neumann's break-throughs in economics, and particularly after his introduction of functional analysis and topology into economic theory, advanced mathematical economics reduced its emphasis on differential calculus. In general equilibrium theory, mathematical economists used general topology, convex geometry, and optimization theory more than differential calculus. In the 1960s and 1970s, however, Gérard Debreu and Stephen Smale led a revival of the use of differential calculus in mathematical economics. In particular, they were able to prove the existence of a general equilibrium, where earlier writers had failed, through the use of their novel mathematics: Baire category from general topology and Sard's lemma from differential topology and differential geometry. Their publications initiated a period of research "characterized by the use of elementary differential topology": "almost every area in economic theory where the differential approach has been pursued, including general equilibrium" was covered by Mas-Colell's monograph on differentiable analysis and economics. Mas-Colell's book "offers a synthetic and thorough account of a major recent development in general equilibrium analysis, namely, the largely successful reconstruction of the theory using modern ideas of differential topology", according to its back cover.