Primary Working Papers

Are “Complementary Policies” Substitutes? Evidence from R&D Subsidies in the UK 

Governments subsidize R&D through a mix of interdependent mechanisms, but subsidy interactions are not well understood. This paper provides the first quasi-experimental evaluation of how R&D subsidy interactions impact firm behavior. I use funding rules and policy changes in the UK to show that direct grants and tax credits for R&D are complements for small firms but substitutes for larger firms. Increasing the generosity of both subsidy types more than doubles small firms’ R&D expenditures, but for larger firms, increasing tax credit rates cuts the positive effect of grants in half. I explore the mechanisms behind these findings and provide suggestive evidence that subsidy complementarity is consistent with easing financial constraints for small firms. Substitution by larger firms is most consistent with the subsidization of infra-marginal R&D expenditures. I rule out some alternative explanations. Subsidy interactions also impact the types of innovation efforts that emerge: with increases in both subsidies, small firms steer efforts increasingly towards developing new goods (i.e., horizontal innovations) as opposed to improving existing goods (i.e., vertical innovations). Accounting for subsidy interactions could substantially improve the effectiveness of public spending on R&D.

Disentangling Uncertainty and Salience (with Eoghan McKenna) [draft undergoing revisions]

Uncertainty and salience lead to different policy implications, but the distinction between them as mechanisms to explain how information affects behavior is not always clear in empirical studies. We use high-frequency data on solar energy generation and electricity consumption to disentangle rational habits from endowment salience effects. We test how providing real-time information regarding onsite solar generation affects household electricity consumption substitution patterns. Preliminary results show that information increases the endowment elasticity by 4 percent on average and up to 18 percent depending on time of day and year. Continued work is exploring the mechanism (i.e., uncertainty versus salience), examining expectation formation, and applying econometric and machine learning methods to derive salience-adjusted self-consumption counterfactuals and welfare effects. The methods can be applied in other settings with misoptimizing consumers.

Other Working Papers

“Information Searching in the Residential Solar PV Market,” [R&R with The Energy Journal] (with Harrison Fell and Ben Sigrin)

“Mission Innovation, Not Mission Impossible” (with Cameron Hepburn, John Rhys, and Niall Farrell) [R&R with Nature Energy

Research in Progress

“The Impact of Environmental Policy on Firms in China” (with Yangsiyu Lu) [preliminary results, extended abstract can be found here]

“Innovation and Entrepreneurship in the Energy Sector” (with David Popp, Ivan Hascic, and Nick Johnstone)

“R&D Subsidy Interactions and Directed Technological Change” [data collected]

“Technology and Environmental Policy Interactions” (with Suganda Srivastav)

“Directed Technological Change: Evidence from Horizon 2020” (with Myra Mohnen and Ralf Martin) [data collected]

Unpublished Working Papers

“Steering the Climate System: An Extended Comment” (with L. Mattauch, R. Millar, F. van der Ploeg, A. Rezai, A. Schultes, F. Venmans, N. Bauer, S. Dietz, O. Edenhofer, N. Farrell, C. Hepburn, G. Luderer, F. Spuler, N. Stern, and A. Teytelboym)