Concerns about the quality of China's official GDP statistics have been a perennial question in understanding its economic dynamics. We use data on satellite-recorded nighttime lights as an independent benchmark for comparing various published indicators of the state of the Chinese economy....

Nighttime lights data are a measure of economic activity whose error is plausibly independent of the measurement errors of most conventional indicators. Therefore, we can use nighttime lights as an independent benchmark to assess existing measures of economic activity (Pinkovskiy and...

I study the impact of transportation on health in the rural US, 1820-1847. Measuring health by average stature, I find that greater transportation linkage, as measured by market access, in a cohort's county-year of birth had an adverse impact on its health. A one-standard deviation increase in...

One of the most important representations of an urban spatial structure is its density. Indeed, an urban area is defined as a densely populated place with a sizeable number of inhabitants. Yet, despite the fact that the defining element of an urban area is its density, few scholars have...

Urban density boosts productivity and innovation, improves access to goods and services, reduces typical travel distances, encourages energy-efficient construction and transport, and facilitates sharing scarce amenities. However, density is also synonymous with crowding, makes living and moving...

Among countries colonized by European powers during the past 500 years those that were relatively rich in 1500 are now relatively poor. We document this reversal using data on urbanization patterns and population density, which, we argue, proxy for economic prosperity. This reversal is...

It is widely believed that correlations between international equity markets tend to increase in highly volatile bear markets. This has led some to doubt the benefits of international diversification. This article solves the dynamic portfolio choice problem of a US investor faced with a...

We evaluate the performance of different models for the covariance structure of stock returns, focusing on their use for optimal portfolio selection. Comparisons are based on forecasts of future covariances as well as the out-of-sample volatility of optimized portfolios from each model. A few...

Fama(1984) analyzed the variability and the covariation of risk premiums and expected rates of depreciation. We employ three statistical techniques that do not suffer from a potential bias in Fama's analysis, but we nevertheless confirm his findings. In contrast to his interpretation the results...

International risk-sharing has far-reaching implications both for economic policy and for basic research in economics. When countries do not share risk, individuals in those countries experience fluctuations in their consumption levels that are undesirable and possibly unnecessary. This paper...