Pier Paolo Creanza

Working papers

Factories of Ideas? Big Business and the Golden Age of American Innovation (Job Market Paper) - Draft available soon

This paper studies the Great Merger Wave (GMW) of 1895-1904—the largest M\&A event in U.S. history—to identify the effect of Big Business (large, market-dominant firms) on American innovation, 1880–1940. Using newly constructed data, I show that firms that consolidated during the GMW substantially increased patenting and breakthrough innovations. Among firms that were already innovating before the GMW, consolidation led to an increase of 6 patents and 0.6 breakthroughs per year—a roughly four-fold and six-fold increase, respectively. Firms with no prior patents were more likely to begin innovating. The establishment of corporate R&D laboratories served as a key mechanism driving these innovation gains. Building a matched inventor–firm panel, I show that lab-owning firms enjoyed a productivity premium not due to inventor sorting, robust within size and technology classes. To assess whether firm-level effects translated into broader technological progress, I examine total patenting within technological domains. Overall, the GMW increased breakthroughs by 13% between 1905 and 1940, with the largest gains in science-based fields (30% increase).

Returning brains:  tax incentives, migration, and scientific productivity - R&R at the Journal of Public Economics

This paper investigates how tax incentives for high-skill immigrants affect productivity. I collect data covering 90 percent of Italian faculty between 2000 and 2020 and use it to evaluate a 2004 tax break targeting researchers. First, the program induced substantial migration and positive selection of beneficiaries. Second, higher-productivity hires significantly increase their academic group's average productivity, roughly split between their direct contribution and indirect responses of local faculty. Third, this indirect effect is largely explained by higher-productivity local researchers sorting into the treated group, rather than by productivity spillovers on incumbent researchers.

Publications

Institutions, trade and growth: the ancient Greek case of proxenia [Paper] [Data] - Journal of Economic History, Volume 84, Issue 1 (Lead Article)

Winner of the 2024 Arthur H. Cole prize for the outstanding contribution on JEH.

Recent scholarship contends that ancient Mediterranean economies grew intensively. An explanation is Smithian growth spurred by reductions in transaction costs and increased trade flows. This paper argues that an ancient Greek institution, proxenia, was among the innovations that allowed such growth in the period 500-0 BCE. Proxenia entailed a Greek city-state declaring a foreigner to be its ‘public friend’, a status that conferred both duties and privileges. Arguably, the functions performed by ‘public friends’ could facilitate economic transactions between communities. Accordingly, network and regression analyses establish a strong relation between proxenia grants and trade intensity.

Work in progress

Industry-Academia Collaborations: Evidence from the GOALI Program
- with Kobi Mizrahi

The changing spatial concentration of innovative activity
- with Pietro Buri

Science Funding: Evidence from Institutional Grants

Teaching and mentoring

Introduction to Microeconomics  (TA, Spring 2024)
- Princeton University, ECO100

Junior Independent Work (TA, A.Y. 2022-2023, A.Y. 2023-2024)
- Princeton University, ECO981

Teaching evaluations available here.