Department of Economics

National and international flows of knowledge are fundamental determinants of technological progress. In this article we review the existing literature on knowledge flows and we propose a method for estimating them, based on patent citations. Citations are links between inventions that reveal a learning process at the technological frontier. We use data for the period 1975-1996 for 147 subnational regions in Europe and North America. We find that geographical distance and technological differences constitute major barriers to knowledge flows. We also show that these flows may have positive, but small, effect on total factor productivity.

In an earlier paper [Rational choice and AGM belief revision, Artificial Intelligence, 2009] a correspondence was established between the set-theoretic structures of revealed-preference theory (developed in economics) and the syntactic belief revision functions of the AGM theory (developed in philosophy and computer science). In this paper we extend the re-interpretation of those structures in terms of one-shot belief revision by relating them to the trichotomous attitude towards information studied in Garapa (Rev Symb Logic, 1–21, 2020) where information may be either (1) fully accepted or (2) rejected or (3) taken seriously but not fully accepted. We begin by introducing the syntactic notion of filtered belief revision and providing a characterization of it in terms of a mixture of both AGM revision and contraction. We then establish a correspondence between the proposed notion of filtered belief revision and the above-mentioned set-theoretic structures, interpreted as semantic partial belief revision structures. We also provide an interpretation of the trichotomous attitude towards information in terms of the degree of implausibility of the information.

We consider decision problems under complete ignorance and extend the minimax regret principle to situations where, after taking an action, the decision maker does not necessarily learn the state of the world. For example, if the decision maker only learns what the outcome is, then all she knows is that the actual state is one of the (possibly several) states that yield the observed outcome under the chosen action. We refer to this situation as imperfect ex-post information. We show that, given a choice between more information and less information, the decision maker prefers the latter. We also extend the framework to encompass the possibility of less than the extreme degree of pessimism that characterizes the minimax regret criterion.

This paper measures social mobility rates in Hungary during the period 1949 to 2017, using surnames to measure social status. In those years, there were two very different social regimes. The first was the Hungarian People's Republic (1949-1989), which was a communist regime with an avowed aim of favouring the working class. The second is the modern liberal democracy (1989-2017), which is a free-market economy. We find five surprising things. First, social mobility rates were low for both upper- and lower-class families during 1949-2017, with an underlying intergenerational status correlation of 0.6-0.8. Second, social mobility rates under communism were the same as in the subsequent capitalist regime. Third, the Romani minority throughout both periods showed even lower social mobility rates. Fourth, the descendants of the eighteenth-century noble class in Hungary were still significantly privileged in 1949 and later. And fifth, although social mobility rates did not change measurably during the transition, the composition of the political elite changed rapidly and sharply.

We examine the price and variety of a sample of consumer goods at the barcode level in cities within China. Unlike the position in the United States, in China the prices of goods tend to be lower in larger cities. We explain that difference between the countries by the more uneven spatial distribution of manufacturers' sales and retailers in China, and we confirm the pro-competitive effect of city size on reducing markups there. In both countries, there is a greater variety of goods in larger cities, but that effect is more pronounced in China. Combining the lower prices and greater variety, the price indexes in China for the goods we study fall with city size by around seven times more than in the United States.

A conclusion of the European Fertility Project in 1986 was that pretransition populations mostly displayed natural fertility, where parity-dependent birth control was absent. This conclusion has recently been challenged for England by new empirical results and has also been widely rejected by theorists of long-run economic growth, where pre-industrial fertility control is integral to most models. In this study, we use the accident of twin births to show that for three Western European-derived pre-industrial populations-namely, England (1730-1879), France (1670-1788), and Québec (1621-1835)-we find no evidence for parity-dependent control of marital fertility. If a twin was born in any of these populations, family size increased by 1 compared with families with a singleton birth at the same parity and mother age, with no reduction of subsequent fertility. Numbers of children surviving to age 14 also increased. Twin births also show no differential effect on fertility when they occurred at high parities; this finding is in contrast to populations where fertility is known to have been controlled by at least some families, such as in England, 1900-1949, where a twin birth increased average births per family by significantly less than 1.

This textbook incorporates the author’s previous book "The Economics of Uncertainty and Insurance" and extends it with the addition of several new chapters on risk sharing, asymmetric information, adverse selection, signaling and moral hazard. It provides a comprehensive introduction to the analysis of economic decisions under uncertainty and to the role of asymmetric information in contractual relationships. It is richly illustrated with 150 figures. It is suitable for both self-study and as the basis for an upper-division undergraduate course. The book is written to be accessible to anyone with minimum knowledge of calculus, in particular the ability to calculate the (partial) derivative of a function of one or two variables. The book contains a total of 150 fully solved exercises.