In this Catalan name, the first or paternal surname is Mas and the second or maternal family name is Colell; both are generally joined by the conjunction "i".
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.[9]
In public service, Mas-Colell was the Commissioner for Universities and Research of the Generalitat of Catalonia in 1999–2000.[2][3][4][5] 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)[11] 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.[2][3][4][5] 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.[4]
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.[9]
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.[12] 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.[6] 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.[13]
Mas-Colell has also contributed to the theory of general equilibrium in topologicalvector lattices.[14] The sets of prices and quantities can be described as partially ordered vector spaces, often as vector lattices. Economies with uncertain or dynamic decisions typically require that the vector spaces be infinite-dimensional, in which case the order properties of vector lattices allow stronger conclusions to be made.[15] Recently researchers have studied nonlinear pricing: A "main motivation came from the fact that Mas-Colell's fundamental theory of welfare economics with no interiority assumptions crucially requires lattice properties of commodity spaces, even in finite-dimensional settings."[16]
Books
Mas-Colell is the author or co-author of:
The Theory of General Economic Equilibrium: a Differentiable Approach (Econometric Society Monographs in Pure Theory 9, Cambridge University Press, 1990, ISBN978-0-521-38870-2). This book was evaluated for Mathematical Reviews by Dave Furth, who wrote that
Mas-Colell's book is one of the first and still one of the most complete and most rigorous of the few textbooks on the applications of differential topology and global analysis to the theory of general economic equilibrium. .... People working in the field ought to own and to have used it already for some time. So those still wanting to consult for the first time and perhaps wanting to buy the book must be mathematicians interested in economic applications of the above-mentioned mathematical subjects. They will not regret consulting and/or buying it; the book is excellent.[17]
Microeconomic Theory (with Michael Dennis Whinston, Jerry R. Green, Oxford University Press, 1995, ISBN978-0-19-507340-9). Johansson (2004) writes that this was "the most commonly used textbook in microeconomics", Jönköping excepted (the investigation covers all economics Ph.D. programs in Sweden for the academic year 2003-04).[8]
Noncooperative approaches to the theory of perfect competition. New York: Academic Press. 1982. ISBN9780124767508.
In honor of his 65th birthday and his service on the European Research Council, two conferences were held in his honor at Pompeu Fabra in 2009, the Journal of Mathematical Economics published a special issue in his honor, and he was awarded the Medal of Honor of the university.[5]
^Back cover: Mas-Colell, Andreu (1985). The Theory of general economic equilibrium: A differentiable approach. Econometric Society monographs. Cambridge UP. ISBN0-521-26514-2. MR1113262.
^Mas-Colell, Andreu (1985). The Theory of general economic equilibrium: A differentiable approach. Econometric Society monographs. Cambridge UP. ISBN0-521-26514-2. MR1113262.
^Aliprantis, Charalambos D.; Brown, Donald J.; Burkinshaw, Owen (1990). Existence and optimality of competitive equilibria. Berlin: Springer-Verlag. pp. xii+284. ISBN3-540-52866-0. MR1075992.
^Page 503 (Chapter 8 "Applications to economics", especially Section 8.5. "Pareto optimality in ordered commodity spaces", and the remainder of the chapter, particularly Section 8.5.11 "Nonlinear pricing")
Mordukhovich, Boris S. (2006). Variational analysis and generalized differentiation II: Applications. Grundlehren Series (Fundamental Principles of Mathematical Sciences). Vol. 331. Springer. pp. i–xxii and 1–610. MR2191745.
^Furth, Dave (1992). "Review of The Theory of general economic equilibrium: A differentiable approach". Mathematical Reviews. MR1113262..