Knowledge that Transforms

Research in experimental economics has cogently challenged the fundamental precept of neoclassical economics that economic agents optimize. The last two decades have seen elaboration of boundedly rational models that try to move away from the optimization approach, in ways consistent with experimental findings. Nonetheless, the collection of alternative models has made little headway supplanting the dominant paradigm. We delineate key ways in which neoclassical microeconomics holds continuing and compelling advantages over bounded-rationality models, and suggest, via a few examples, the sorts of further, difficult pushes that would be needed to redress this state of affairs. Closer collaboration between theoretic modeling and experiments is clearly seen to be necessary. (JEL B40, C72, C90, D01, D21)

The choice of an overall discount rate for climate change investments depends critically on how different components of investment payoffs are discounted at differing rates reflecting their underlying risk characteristics. Such underlying rates can vary enormously, from ≈ 1 percent for idiosyncratic diversifiable risk to ≈ 7 percent for systematic nondiversifiable risk. Which risk-adjusted rate is chosen can have a huge impact on cost-benefit analysis. In this expository paper, I attempt to set forth in accessible language with a simple linear model what I think are some of the basic issues involved in discounting climate risks. The paper introduces a new concept that may be relevant for climate-change discounting: the degree to which an investment hedges against the bad tail of catastrophic damages by insuring positive expected payoffs even under the worst circumstances. The prototype application is calculating the social cost of carbon. (JEL C51, Q54, Q58)

Harstad and Selten (this forum) raise interesting questions about the relative promise of optimization models and bounded-rationality models in making progress in economics. This article builds from their analysis by indicating the potential for using neoclassical (broadly defined) optimization models to integrate insights from psychology on the limits to rationality into economics. I lay out an approach to making (imperfect and incremental) improvements over previous economic theory by incorporating greater realism while attempting to maintain the breadth of application, the precision of predictions, and the insights of neoclassical theory. I then discuss how many human limits to full rationality are, in fact, well understood in terms of optimization. (JEL B49, D01, D03, D81, D84)

This paper provides a survey of business cycle facts, updated to take account of recent data. Emphasis is given to the Great Recession, which was unlike most other postwar recessions in the United States in being driven by deleveraging and financial market factors. We document how recessions with financial market origins are different from those driven by supply or monetary policy shocks. This helps explain why economic models and predictors that work well at some times do poorly at other times. We discuss challenges for forecasters and empirical researchers in light of the updated business cycle facts.

I survey the evidence on patterns in U.S. high school graduation rates over the period 1970–2010 and report the results of new research conducted to fill in holes in the evidence. I begin by pointing out the strengths and limitations of existing data sources. I then describe six striking patterns in graduation rates. They include stagnation over the last three decades of the twentieth century, significant race-, income-, and gender-based gaps, and significant increases in graduation rates over the first decade of the twenty-first century, especially among blacks and Hispanics. I then describe the models economists use to explain the decisions of individuals to invest in schooling, and examine the extent to which the parameters of the models explain recent patterns in graduation rates. I find that increases in the nonmonetary costs of completing high school and the increasing availability of the GED credential help to explain stagnation in the face of substantial gaps between the wages of high school graduates and school dropouts. I point out that there are several hypotheses, but to date, very little evidence to explain the increases in high school graduation rates over the first decade of the twenty-first century. I conclude by reviewing the evidence on effective strategies to increase high school graduation rates, and explaining why the causal evidence is quite modest. (JEL I21, J15, J16)

Households “sort” across neighborhoods according to their wealth and their preferences for public goods, social characteristics, and commuting opportunities. The aggregation of these individual choices in markets and in other institutions influences the supply of amenities and local public goods. Pollution, congestion, and the quality of public education are examples. Over the past decade, advances in economic models of this sorting process have led to a new framework that promises to alter the ways we conceptualize the policy evaluation process in the future. These “equilibrium sorting” models use the properties of market equilibria, together with information on household behavior, to infer structural parameters that characterize preference heterogeneity. The results can be used to develop theoretically consistent predictions for the welfare implications of future policy changes. Analysis is not confined to marginal effects or a partial equilibrium setting. Nor is it limited to prices and quantities. Sorting models can integrate descriptions of how nonmarket goods are generated, estimate how they affect decision making, and, in turn, predict how they will be affected by future policies targeting prices or quantities. Conversely, sorting models can predict how equilibrium prices and quantities will be affected by policies that target product quality, information, or amenities generated by the sorting process. These capabilities are just beginning to be understood and used in applied research. This survey article aims to synthesize the state of knowledge on equilibrium sorting, the new possibilities for policy analysis, and the conceptual and empirical challenges that define the frontiers of the literature. (JEL C63, D04, E61, H41, R23, R31, R38)

The agricultural and food sector is an ideal case for investigating the political economy of public policies. Many of the policy developments in this sector since the 1950s have been sudden and transformational, while others have been gradual but persistent. This article reviews and synthesizes the literature on trends and fluctuations in market distortions and the political-economy explanations that have been advanced. Based on a rich global data set covering a half-century of evidence on commodities, countries, and policy instruments, we identify hypotheses that have been explored in the literature on the extent of market distortions and the conditions under which reform may be feasible. (JEL F13, Q11, Q17, Q18)

How has publishing in top economics journals changed since 1970? Using a data set that combines information on all articles published in the top-five journals from 1970 to 2012 with their Google Scholar citations, we identify nine key trends. First, annual submissions to the top-five journals nearly doubled from 1990 to 2012. Second, the total number of articles published in these journals actually declined from 400 per year in the late 1970s to 300 per year most recently. As a result, the acceptance rate has fallen from 15 percent to 6 percent, with potential implications for the career progression of young scholars. Third, one journal, the American Economic Review, now accounts for 40 percent of top-five publications, up from 25 percent in the 1970s. Fourth, recently published papers are on average three times longer than they were in the 1970s, contributing to the relative shortage of journal space. Fifth, the number of authors per paper has increased from 1.3 in 1970 to 2.3 in 2012, partly offsetting the fall in the number of articles per year. Sixth, citations for top-five publications are high: among papers published in the late 1990s, the median number of Google Scholar citations is 200. Seventh, the ranking of journals by citations has remained relatively stable, with the notable exception of the Quarterly Journal of Economics, which climbed from fourth place to first place over the past three decades. Eighth, citation counts are significantly higher for longer papers and those written by more coauthors. Ninth, although the fraction of articles from different fields published in the top five has remained relatively stable, there are important cohort trends in the citations received by papers from different fields, with rising citations to more recent papers in Development and International, and declining citations to recent papers in Econometrics and Theory. (JEL A14)

China's ongoing urban economic growth has sharply increased the population's per capita income, lowered the count of people living below the poverty line, and caused major environmental problems. We survey the growing literature investigating the causes and consequences of China's urban pollution challenges. We begin by studying how urban population and industrial growth impacts local pollution levels and greenhouse gas production. As the urban population grows richer, its demand for private transportation and electricity sharply increases. Such privately beneficial activity exacerbates urban pollution externalities. Facing these severe environmental challenges, China's urbanites increasingly demand quality of life progress. We survey the emerging literature investigating the demand for environmental progress in China. Progress in mitigating externalities hinges on whether the powerful central and local governments choose to address these issues. We analyze the political economy of whether government officials have strong incentives to tackle lingering urban externalities. We conclude by discussing future research opportunities at the intersection of environmental and urban economics. (JEL O18, P25, P28, Q53, R23, R41, R58)

Presenting data on all full-length articles in the three top general economics journals for one year in each decade 1960s–2010s, I analyze changes in patterns of coauthorship, age structure and methodology, and their possible causes. The distribution of number of authors has shifted steadily rightward. In the last two decades, the fraction of older authors has almost quadrupled. Top journals are publishing many fewer papers that represent pure theory, regardless of subfield, somewhat less empirical work based on publicly available data sets, and many more empirical studies based on data collected by the author(s) or on laboratory or field experiments. (JEL A14)