Song Ma

Yale School of Management
165 Whitney Avenue
New Haven, CT 06511
Tel: (203) 436-4687

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NBER Working Papers and Publications

May 2016How Does Hedge Fund Activism Reshape Corporate Innovation?
with Alon Brav, Wei Jiang, Xuan Tian: w22273
This paper studies how hedge fund activism reshapes corporate innovation. Firms targeted by hedge fund activists experience an improvement in innovation efficiency during the five-year period following the intervention. Despite a tightening in R&D expenditures, target firms experience increases in innovation output, measured by both patent counts and citations, with stronger effects seen among firms with more diversified innovation portfolios. We also find that the reallocation of innovative resources and the redeployment of human capital contribute to the refocusing of the scope of innovation. Finally, additional tests refute alternative explanations attributing the improvement to mean reversion, sample attrition, management’s voluntary reforms, or activists’ stock-picking abilities.

Published: Alon Brav & Wei Jiang & Song Ma & Xuan Tian, 2018. "How does hedge fund activism reshape corporate innovation?," Journal of Financial Economics, .

January 2014Firm Age, Investment Opportunities, and Job Creation
with Manuel Adelino, David T. Robinson: w19845
This paper asks whether startups react more to changing investment opportunities than more mature firms do. We use the fact that a region's pre-existing industrial structure creates exogenous variation in the severity of its exposure to nation-wide manufacturing shocks to develop an instrument for changing investment opportunities, and examine employment creation in the non-tradable sector as a response to those opportunities. Startups are much more responsive to changing local economic conditions than older firms. Moreover, their responsiveness doubles in areas with better access to small business finance, suggesting that financing constraints are an important brake on job creation in the startup sector. Although we focus mostly on the non-tradable sector for empirical identification,...

Published: MANUEL ADELINO & SONG MA & DAVID ROBINSON, 2017. "Firm Age, Investment Opportunities, and Job Creation," The Journal of Finance, vol 72(3), pages 999-1038.

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