Papers In Preparation

Passive Ownership and Price Informativeness (Updated 4/2021)

A copy of the paper can be found here (PDF). The online appendix can be found here (PDF).

Note on the equivalence of total learning capacity across rotated economies (PDF). SSRN Link

Abstract: Despite the rapid growth of passive ownership over the past 30 years, there is no consensus on how or why passive ownership affects stock price informativeness. This paper provides a new answer to this question by examining how passive ownership changes investors’ incentives to acquire information. I develop a model where passive ownership affects how many investors gather information, and how investors allocate attention between systematic and idiosyncratic risk. The model also links investors’ learning decisions to price informativeness through quantities that are readily observable in the data: trading volume, returns and volatility. The model’s predictions motivate three new measures of price informativeness, all of which declined on average over the past 30 years. In the cross-section, increases in passive ownership are negatively correlated with price informativeness. To establish causality, I show that price informativeness decreases after quasi-exogenous increases in passive ownership arising from index additions and rebalancing.

Previously circulated under the title “Earnings Announcements and the Rise of Passive Ownership”

Firm Customer Bases: Churn and Networks (Updated 11/2020)

Joint with Scott Baker and Brian Baugh

New: Firm-level data

A copy of the paper can be found here (PDF)


Abstract: Can an increasingly accessible type of household financial data yield new insights about firm-specific risk? We develop two new measures characterizing firms’ customer bases – the rate of churn in a firm’s customer base and the pairwise similarity between firms’ customer bases – using household financial transaction data. We validate our approach by using the data to construct accurate pictures of firm revenue, growth, geographic dispersion, and customer base characteristics. We show that these measures of customer bases are impossible to construct utilizing traditional sources of firm data, but provide important insights into the behavior of both real firm decisions and firm asset prices. Rates of customer churn affect the level and volatility of firm-level investment, markups, and profits. Churn also affects how quickly firms respond to shocks in the value of their growth options (i.e. Tobin’s Q). Moreover, high churn firms tended to face steeper declines in consumer spending during the recent COVID-19 outbreak. Similarity between firms’ customer bases highlights one under-explored type of predictability among stock returns – we demonstrate that significant alpha can be generated using a trading strategy that exploits our index of customer base similarity across firms.

What Triggers National Stock Market Jumps? (Updated 11/2020)

Our data is now live

Joint with Scott Baker, Nicholas Bloom and Steven Davis

A copy of the paper can be found here (PDF)

We examine newspapers the day after major stock-market jumps to evaluate the proximate cause, geographic source, and clarity of these events from 1900 in the US and 1980 (or earlier) in 13 other countries. We find four main results. First, the United States plays an outsized role in global stock markets, accounting for 35% of jumps outside the US since the 1980s. Second, policy causes a higher share of positive than negative jumps in all countries we examine. Monetary policy and government spending jumps are the most over-represented in positive jumps, suggesting major policy announcements are usually in response to negative shocks. Third, jumps caused by non-policy events (particularly macroeconomic news) lead to higher future volatility, while jumps caused by policy events (particularly monetary policy) reduce future volatility. Finally, the clarity of the cause of stock market jumps has increased substantially since 1900 as news and financial markets have become more transparent. Jump clarity predicts future stock returns volatility: doubling the clarity of a jump reduces future volatility by 68%.

Retail Investors’ Contrarian Behavior Around News and the Momentum Effect (Updated 11/2020)

Joint with Cheng (Patrick) Luo, Enrichetta Ravina and Luis M. Viceira

A copy of the paper can be found here (PDF)


We study the role of retail investors in the gradual diffusion of information in financial markets. We show that retail investors tend to trade as contrarians after large earnings surprises, and such contrarian trading contributes to sluggish price adjustment and to momentum. Retail traders are particularly active for small loser stocks. As a robustness check, we double sort stocks in quintiles based on momentum and the strength of retail contrarian trading, and find that the momentum phenomenon arises only in the 4th and 5th quintile of contrarian trading intensity. We further investigate the timing and the horizon of the traders, the role of segmentation in stock ownership, and the role of attention and browsing behavior in generating contrarian trading. Alternative hypotheses, such as the disposition effect, and stale limit orders, do not explain the phenomenon.

Trade Policy Uncertainty and Stock Returns (Updated 7/2020)

Revise and Resubmit at the Journal of International Money and Finance

Joint with Marcelo Bianconi and Federico Esposito

A copy of the paper can be found here (PDF)


Abstract: A recent literature has documented large real effects of trade policy uncertainty (TPU) on supply chains, employment, and investment, but there is little evidence that investors are compensated for bearing such risk. To quantify the risk premium associated with TPU, we exploit quasi-experimental variation in exposure to TPU arising from Congressional votes to revoke China’s preferential tariff treatment between 1990 and 2001. A long-short portfolio designed to isolate exposure to TPU earns a risk-adjusted return of 6% per year. This effect is larger in sectors less protected from globalization, and more reliant on inputs from China. Industries more exposed to trade policy uncertainty also had a larger drop in stock prices when the uncertainty began, and more volatile returns around key policy dates. Our results are not explained by the effects of policy uncertainty on expected cash-flows, investors’ forecast errors, and import competition from China.

Published Papers

The Unprecedented Stock Market Reaction to COVID-19 (The Review of Asset Pricing Studies, July 2020)

Joint with Scott Baker, Nicholas Bloom, Steven J. Davis, Kyle Kost, and Tasaneeya Viratyosin.

A copy of the paper can be found here (PDF)

Publisher link

Abstract: No previous infectious disease outbreak, including the Spanish Flu, has impacted the stock market as forcefully as the COVID-19 pandemic. In fact, previous pandemics left only mild traces on the U.S. stock market. We use text-based methods to develop these points with respect to large daily stock market moves back to 1900 and with respect to overall stock market volatility back to 1985. We also evaluate potential explanations for the unprecedented stock market reaction to the COVID-19 pandemic. The evidence we amass suggests that government restrictions on commercial activity and voluntary social distancing, operating with powerful effects in a service-oriented economy, are the main reasons the U.S. stock market reacted so much more forcefully to COVID-19 than to previous pandemics in 1918-19, 1957-58 and 1968.

Environmental, Social, and Governance Criteria: Why Investors Are Paying Attention (Journal of Investment Management, January 2018)

Joint with Ravi Jagannathan and Ashwin Ravikumar


A copy of the paper can be found here (PDF)

Abstract: We find that money managers could reduce portfolio risk by incorporating Environmental, Social, and Governance (ESG) criteria into their investment process. ESG-related issues can cause sudden regulatory changes and shifts in consumer tastes, resulting in large asset price swings which leave investors limited time to react. By incorporating ESG criteria in their investment strategy, money managers can tilt their holdings towards firms which are well prepared to deal with these changes, thereby managing exposure to these rare but potentially large risks.