Publications
Inventor Mobility Under Uncertainty (with D.Czarnitzki & T.Doherr)
Research Policy, Volume 53, Issue 1, January 2024, 104896
Winner - Best paper award at the 2022 KID Summer School
Abstract: Previous work suggests a general uncertainty surrounding the migration process acts as a barrier to outmigration. In this paper, we argue that this barrier is exacerbated when relative economic policy uncertainty is higher in the target country and mitigated when relatively higher in the origin country. We create an inventor career panel to observe inventor migration between 12 European countries between 1997 and 2012. This allows us to test the premise that a higher relative uncertainty in the origin country raises the probability of inventor outmigration. Our results suggest a 1 standard deviation increase in the relative uncertainty of the home country is associated with a near 20% increase in the probability of inventor outmigration. The relationship is highly non-linear, with relative uncertainty values in the top centile leading to an increase of over 70%. The observed effects can be amplified or dampened by inventor specific characteristics, as would be expected given the prior art.
Specialisation and the Career Outcomes of Inventors
Research Policy, Volume 55, Issue 5, June 2026, 105477
Abstract: Recent years have seen a reorganisation of innovation production to favour groups of collaborators, and increasingly specialised inventors. In this paper, I construct a panel of highly prolific inventors whom I observe frequently throughout their career. I develop a simple setting whereby inventors face a trade-off between acquiring knowledge depth and knowledge breadth. Empirically, I find that, after controlling for selection into specialised careers, knowledge depth is consistently negatively associated with the probability that an inventor contributes to an invention which receives citations in the top quantile. The negative effects largely hold across technological fields and, across the inventor's career cycle. The negative relationship between specialisation and highly-cited inventions is concerning given the disproportionate value of such inventions to society.
Working Papers
Abstract: I provide novel evidence that childcare stimulates invention by insulating inventors who become mothers from the negative productivity effects of childbirth. I use patent-matched employment histories of German inventors to observe the careers of inventors during a period in which federal policy pushed German regions to expand under-3 childcare towards a national target, from different starting points. I find that greater childcare coverage significantly attenuates the large and persistent decline in both inventive output and the probability of remaining an inventor that women experience after they become mothers. The effect seems to be driven by an increase in labour supply in the three-year period while their child is under the age of 3. However, the positive effects on the quantity and quality of patenting persist well beyond this window. These results offer a new avenue through which policy can prevent women from exiting careers as inventors.
Intellectual Mobility Frictions (with D. Verhoeven)
Winner - Heinz König Award (best paper at the 2024 Economics of Innovation and Patenting conference at ZEW)
Abstract: Despite repeated findings that intellectually mobile inventors - those with experience in multiple technological fields - have a comparative advantage in the production of the highest value inventions, aggregate evidence suggests that the share of intellectually mobile inventors is falling. In this paper, we propose the presence of allocation frictions which increase the cost a firm must pay to allocate inventors to a technological field in which they have not previously invented. We create a simple framework to estimate these frictions at the micro-level and find them to be very high in magnitude, and heterogeneous across firms and the technological space. Counterfactual estimates suggest that even moderate decreases in these allocation frictions could increase idea generation by 50%.
Work in Progress
Immigrants and Ideas (with L. Steines)