Research
Research
Information and Innovation: Evidence From Railroad Expansion in the Nineteenth Century (Solo-Authored)
I study the causal effect of information flows on innovation by exploiting the staggered expansion of the U.S. railroad network between 1840 and 1900. Using the opening of the first railroad in each county as a quasi-natural experiment, I find that counties connected by rail subsequently generated more patents over the following five years relative to counties without access. These patents tend to be more important and impactful, though less novel. The effect is stronger in counties that became more connected to other counties through the rail network. Leveraging text-based patent similarity measures constructed with large-language-model embeddings, I further show that, once two counties were newly linked by rail, a county’s patents became more similar to the patents produced in its newly connected counterpart counties. Taken together, these findings suggest that improved efficiency in information exchange enhanced innovative activity and highlight information diffusion as an underlying channel driving innovation.
Presentations: 2025 FMA Doctoral Student Consortium, 2026 AFA PhD Student Poster Session (scheduled)
The Value of Stock Analyses (with Zhen Shi, Yusen Xia, and Baozhong Yang)
This study examines whether financial journalism provides value-relevant insights beyond corporate disclosures. Using large language models, we match news coverage in WSJ articles to firm disclosures in 8-K filings and decompose news content into components that reiterate corporate releases and that provide incremental information and analysis. We find that WSJ articles incorporate substantial analytical commentary on macroeconomic conditions, competitive dynamics, regulatory challenges, and technological innovations. Sentiment in this incremental analysis predicts substantial short-term abnormal returns, long-term stock performance, and future operating performance. Effects are more pronounced among firms with high information asymmetry. Our findings demonstrate that financial journalism delivers material insights beyond regulatory disclosures, thereby enhancing price discovery in capital markets.
Presentations: The 38th Australasian Finance and Banking Conference - Keynote Speech (scheduled), Georgia State University RISE Success Forum 2024
The Impact of Improved Accessibility through Railroads on Entrepreneurship (with Jing (Sophia) Xue and Baozhong Yang)
We study the impact of improved accessibility on entrepreneurial activity in the context of the late nineteenth-century expansion of the U.S. railroad network. The spread of railroads connected distant regions, facilitated knowledge transfer, and lowered barriers to entry into new markets. Exploiting the staggered rollout of railroad routes across different regions as a quasi-experimental setup, we examine two central questions: (1) How did railroad expansion affect individuals’ decisions to engage in entrepreneurship versus wage employment? and (2) To what extent did improved accessibility foster labor mobility, occupational change, and the emergence of technological entrepreneurship? Overall, this study highlights how improved accessibility reshaped patterns of entrepreneurship activity.
A Dataset for Historical Innovation Studies: The Demographics of Innovators in the 19th and 20th Centuries (with Tania Babina, Jing (Sophia) Xue and Baozhong Yang)
We construct a longitudinal inventor-level dataset by linking historical patent records from the United States Patent and Trademark Office (USPTO) with full-count census data from the nineteenth and early twentieth centuries. This linkage connects inventors’ entrepreneurial activities (e.g., patenting) with demographic and occupational information, enabling us to observe changes in residence, occupation, industry affiliation, and broader patterns of mobility and employment choices.