Knowledge that Transforms

What is the demand elasticity of statistical arbitrageurs that invest according to the advice of modern cross-sectional asset pricing models? Thirteen models from the literature exhibit strikingly inelastic demand, in contrast to classical models that rely on statistical arbitrageurs to create elastic market demand for assets. This inelasticity arises from the difficulty of trading against price changes. A quantitative equilibrium model shows that aggregate demand remains inelastic even with these statistical arbitrageurs in the market.

The availability of big data and analytics expertise provides insurers with informational advantages over policyholders in estimating risk. We study competition between heterogeneously informed insurers, showing that their information may or may not be revealed in equilibrium. We find that all equilibria are profitable and that noninformative equilibria entail risk pooling and possibly efficiency. In informative equilibria, the signaling problem interacts with the screening problem that arises endogenously from insurers’ revelation of information, implying underinsurance. Our main insights are robust to changes in insurers’ information precision and market concentration and to the presence of two-sided asymmetric information and withdrawable contracts.

We study how the social transmission of public news influences investors’ beliefs and the securities markets. Using data on social networks, we find that earnings announcements from firms in higher-centrality counties generate a stronger immediate price, volatility, and trading volume reactions. Post-announcement, such firms experience weaker price drift and faster volatility decay but higher and more persistent volume. These findings suggest greater social connectedness facilitates the timely incorporation of news into prices, as well as opinion divergence and excessive trading. We propose the social churning hypothesis, which is confirmed using granular data from StockTwits messages and household trading records.

Firms enter new sectors by either building on their resources or buying existing companies. Using French administrative data, we propose a measure of human capital distance between a firm and a sector of entry. Using a shift-share instrument, we show that firms build in close sectors and buy in distant sectors in terms of human capital distance. Firms build by hiring new workers, which becomes increasingly costly in distant sectors as it requires not only hiring more workers but also having more organizational capital to integrate these workers. Hence, firms buy in distant sectors to acquire already operational human capital.

We highlight the limitations of using cumulative advertising expenses as an input measure of brand value. Using two output measures—Interbrand’s data and a novel text-based measure—we find that an equal-weighted portfolio of top brands yields an annual abnormal return of 3%. The excess returns are driven by companies that develop their brands internally. Intangible factors proposed in the literature have no explanatory power for the premium. Analysts underestimate the future earnings of top brands, leading to significant excess returns following earnings announcements. We find no abnormal returns associated with the input measure of brand value.

A number of delta-hedged equity option strategies exhibit very large average returns. We show that much of the profitability of these strategies can be explained by an IPCA factor model. The economic magnitude of the return-adjustment produced by IPCA is impressive: even before transaction costs, the average IPCA alpha of 46 long-short trading strategies constructed on previously discovered signals, is close to zero and contrasts with average realized returns of over 80 basis points per month. Our IPCA model can be used as a benchmark for assessing the performance of other option portfolios.

Variation in monthly metro area house prices unrelated to expected rents clouds the information about future rents in price-rent ratios and lagged changes in house prices. The variation in house prices unrelated to expected rents is, however, correlated across areas, and the problem is mitigated by measuring rent growth regression variables net of their monthly cross-section (across-area) means. This control for price variation unrelated to expected rents substantially enhances the information about future rents that we extract from price-rent ratios and lagged changes in house prices.

I show that shocks to financial intermediaries supplying hedging instruments to corporations have real effects. I exploit a quasi-natural experiment in South Korea in 2010, where regulations required banks to hold enough capital for taking foreign exchange derivatives (FXD) positions. Using variation in exposure to this regulation across banks, I find that the regulation caused a reduction in FXD supply, leading to a significant decline in exports for firms contracting derivatives with more exposed banks. Results indicate the crucial role of intermediaries in allocating risks through derivatives provision and establish a causal relationship between financial hedging and real economic outcomes.

There is causal evidence that mortgage credit expansions increase house prices. Does an expansion of margin lending increase stock prices? Because unconstrained arbitrageurs are more important for pricing stocks than homes, the impact is not obvious. Tests are limited because sizable shocks to margin lending are rare. We examine a major Chinese margin-lending expansion between 2010 and 2015. Institutional holding, regression discontinuity, and event study evidence—exploiting the rollout of margin lending across stocks—shows that arbitrageurs anticipated and bought in advance of a significant causal effect of credit. We develop a model to rationalize our findings. Our estimates suggest that margin debt contributes to stock market fluctuations.

We present evidence that loan allocations and loan terms are closely linked to the strength of social connections between bank and borrower regions. Lending increases with social connectedness, particularly in the presence of strong screening incentives. If connectedness is high, banks discriminate between borrowers more, the terms of originated loans are more borrower friendly, and loan performance is better. Furthermore, social connectedness is associated with higher bank profitability and with lending-related increases in borrower-region GDP growth and employment. Our results suggest that lending barriers decrease with social connectedness, which helps our understanding of geographic lending patterns and regional economic disparities.