Research Interests

My research interests are in networks relating to digitization, investments, political connections, and innovation.

Working Papers

Abstract: I document that the network structure of the online economy significantly contributes to rising industry concentration.  Firms that are central in the online economy are aided by feedback effects that drive users to their websites, providing further benefits via economies of scale and network effects.  Industries with firms that are more central become more concentrated and central firms have larger increases in market share during the sample period.  It appears that central firms are better able to generate revenue, as central firms earn higher risk-adjusted returns and have more positive earnings surprises.  Finally, centrality is more strongly associated with increasing productivity than decreasing competition, providing generally positive welfare implications.

2021 American Finance Association Meeting  (Chicago, IL)

Abstract: We develop an extensive mapping of the revolving door phenomenon in the U.S. by examining the work experience of 420,153 individuals in top corporate positions at 12,869 firms. More than half of these firms have at least one such individual with prior experience in one of 187 executive branch agencies. Consistent with the “knowledge” hypothesis, firms are more likely to receive procurement contracts following the appointment of a former regulator transitioning within two years of leaving the agency. Problematically, contracts signed following the appointment of former regulators are more likely to be renegotiated, resulting in higher costs for the government.

Media Coverage: Columbia Law School Blue Sky Blog

Abstract: We examine the relation between patent thickets and acquisitions. Patent thickets are dense webs of overlapping intellectual property rights that create costs by complicating licensing negotiations and increasing the risk of holdup and litigation. We find that firms are less likely to be acquired when they are in a denser thicket comprised of many patent owners, which exposes firms to these costs. In contrast, firms are more likely to be acquired when the thicket created by their own patents is denser, which insulates firms from these costs. We also find that when the acquirer and target occupy the same thicket, the target is more likely to be acquired when they can impose these costs on the acquirer but less likely to be acquired when they can have these costs imposed on them by the acquirer. Importantly, our results are not explained by patent count, patent citations, or technological overlap. Overall, we show that patent thickets play an important role when acquiring innovation.

2018 Western Finance Association Meeting  (Coronado, CA)

Abstract: Using investor internet access, we show that increased information access leads to decreased geographic bias in retail investor portfolios, although this ultimately harms the portfolio performance. With internet access improving information access, investors must choose whether to focus their attention on local or distant stocks, subsequently increasing or decreasing their geographic bias, respectively. We find that investors are more likely to invest in more distant stocks after starting to trade online. This is especially true for investors from rural areas and the southern region of the U.S. However, online investors are less likely to invest in new industries, increase their trend-chasing behavior, and appear to lose their advantage in local holdings, resulting in decreased Sharpe ratios despite the diversification benefits. The evidence is most consistent with distant stocks grabbing the attention of online investors and distracting them from their competitive advantage. Our findings demonstrate that while information access provides benefits for investors, it can also exacerbate behavioral biases, which places additional responsibility on investors to carefully manage how they use their access. 

Works in Progress

Web-Based Peers: Peer Groups for Public and Private Firms