Knowledge that Transforms

We propose a unified model of limited market integration, asset-price determination, leveraging, and contagion. Investors and firms are located on a circle, and access to markets involves participation costs that increase with distance. Due to a complementarity between participation and leverage decisions, the equilibrium may exhibit diverse leverage and participation choices across investors, although investors are ex ante identical. Small changes in market-access costs can cause a change in the type of equilibrium, leading to discontinuous price changes, deleveraging, and portfolio-flow reversals. Moreover, the market is subject to contagion—an adverse shock to investors in some locations affects prices everywhere. (JEL D83, G11, G12, G32, G35)

We model a financial market in which investor beliefs are shaped by representativeness. Investors overreact to a series of good news, because such a series is representative of a good state. A few bad news do not change investor minds because the good state is still representative, but enough bad news leads to a radical change in beliefs and a financial crisis. The model generates debt over-issuance, “this time is different” beliefs, neglect of tail risks, under- and over-reaction to information, boom-bust cycles, and excess volatility of prices in a unified psychological model of expectations.

In many economic, political, and social situations, circumstances change at random points in time, reacting is costly, and reactions appropriate to present circumstances may become inappropriate upon future changes, requiring further costly reaction. Waiting is informative if arrival of the next change has non-constant hazard rate. We identify two classes of situations: in the first, delayed reaction is optimal only when the hazard rate of further changes is decreasing; in the second, it is optimal only when the hazard rate of further changes is increasing. These results in semi-Markovian decision theory provide motivations for building delay into decision systems. (JEL C61, D72, D82, D83, K10, M11)

A seven-year randomized evaluation suggests education subsidies reduce adolescent girls' dropout, pregnancy, and marriage but not sexually transmitted infection (STI). The government's HIV curriculum, which stresses abstinence until marriage, does not reduce pregnancy or STI. Both programs combined reduce STI more, but cut dropout and pregnancy less, than education subsidies alone. These results are inconsistent with a model of schooling and sexual behavior in which both pregnancy and STI are determined by one factor (unprotected sex), but consistent with a two-factor model in which choices between committed and casual relationships also affect these outcomes.

We revisit to what extent the increase in income inequality since 1980 was mirrored by consumption inequality. We do so by constructing an alternative measure of consumption expenditure using a demand system to correct for systematic measurement error in the Consumer Expenditure Survey. Our estimation exploits the relative expenditure of high- and low-income households on luxuries versus necessities. This double differencing corrects for measurement error that can vary over time by good and income. We find consumption inequality tracked income inequality much more closely than estimated by direct responses on expenditures. (JEL D31, D63, E21)

In this article, I present three key facts about income and wealth inequality in the long run emerging from my book Capital in the Twenty-First Century and seek to sharpen and refocus the discussion about those trends. In particular, I clarify the role played by r > g in my analysis of wealth inequality. I also discuss some of the implications for optimal taxation, and the relation between capital-income ratios and capital shares.

Using two independent data sources—the intrafirm trade data from the US Bureau of Economic Analysis and the related party trade data from the US Census Bureau—I construct and compare measures of US intrafirm exports and imports. I find that, in general, the two datasets provide similar measures of US intrafirm trade, particularly for exports. Understanding the differences that do exist in measurement will likely require study of the confidential micro data at both the Bureau of Economic Analysis and the Census Bureau.

Rising household wealth may potentially impact both total fuel consumption and fuel-type composition, resulting in significant health and environmental implications. Using data from a field experiment in India, we explore the effects of a transfer program that provided poor, rural households with greater levels of assets and cash. Total fuel consumption rose as a result of the transfers. Households shifted from using electricity rather than kerosene as their primary form of light, but total kerosene consumption also rose. In contrast, we did not observe a shift to cleaner cooking fuels.

In this paper we analyze elections when voters underestimate the correlation between their information sources (“correlation neglect”). We find that this cognitive bias can improve political outcomes. We show that the extreme beliefs which result from correlation neglect induce some voters to base their vote on information rather than on political preferences. We characterize conditions on the distribution of preferences under which this induces higher vote shares for the optimal policies and better information aggregation. (JEL D72, D83)

We explore time trends in the labor force participation of veterans and non-veterans and investigate whether they are consistent with a rising role for the Department of Veterans Affairs' Disability Compensation (DC) program, which pays benefits to veterans with service-connected disabilities and has grown rapidly since 2000. Using 35 years of March CPS data, we find that veterans' labor force participation declined over time in a way that coincides closely with DC growth and that veterans have become more sensitive to economic shocks. Our findings suggest that DC program growth has contributed to recent declines in veterans' labor force participation.