+ Yuan Hu | Economics | Imperial College London

Publications

  • Agglomeration Costs Limit Sustainable Innovation in Cities in Developing Economies

    with Saul Estrin, Daniel Shapiro and Peng Zhang; PLoS ONE 19(11): e0308742.(2024)
    Kudos research summary

  • Working Papers

    • Green Technological Change After Natural Disasters: Evidence from Hurricane Katrina

      Job Market Paper
      Media Coverage: CEPR VoxEU Talk
      Abstract: Climate change leads to more destructive natural disasters, particularly hurricanes, which can significantly disrupt knowledge production. This paper studies the effects of Hurricane Katrina — one of the costliest and deadliest storms in U.S. history — on inventors' innovation outcomes, including green innovation which helps combat climate change. Using hazard and patent data for U.S. inventors in a difference-in-differences design, I find that Katrina reduced inventors' production of green patents, while non-green patents were unaffected. Specifically, affected inventors could have produced an additional 0.220 green patents following the storm, i.e., a potential 415 percent increase, had Katrina not occurred. The negative effects are driven by the greater distance in technological expertise (knowledge diversity) among collaborators in green innovation teams, making it harder to substitute for affected inventors and continue their technological tasks. These findings suggest that climate change can disrupt human efforts aimed at addressing its impact, particularly through natural disasters and that knowledge diversity can compromise the resilience of technological development when faced with disruptions.

    • Exporting Modes as Learning Strategies: A Penrosian Approach

      with Saul Estrin and Lilac Nachum
      Under Review, Journal of Management
      Abstract: The learning outcomes of alternative export strategies on firms’ innovation are inconclusive. We focus on the simultaneous pursuit of direct and indirect exporting rather than the choice of one between them. Adopting a Penrosian perspective, we suggest that the generation of excess resources in the course of the pursuit of one export strategy provides resources for expansion to the other, enabling the more effective execution of both. This approach enables firms to benefit from learning opportunities of the two export strategies as well as from the synergistic effects between them, thus increasing their innovation performance compared to firms that pursue each of these strategies singly. We also suggest that these relationships are contingent on the characteristics of firms and those of their learning environment. Testing these predictions on a sample of African exporters included in World Bank Enterprise Surveys provides strong support for the superiority of the combined export strategy as a learning venue that is robust across multiple specifications and estimation techniques. The development and testing of the theory in Africa enable us to observe the impact of context on learning via exporting and deepen the understanding of the contingencies that determine this outcome.