Research

Working papers

Why is productivity slowing down? (with Ian Goldin, Pantelis Koutroumpis, Nils Rochowicz and Julian Winkler), under review
We comprehensively review the explanations for the current productivity slowdown

Journal articles

Wright meets Markowitz: How standard portfolio theory changes when assets are technologies following experience curves  (with Rupert Way, Valentyn Panchenko, Fabrizio Lillo, and J. Doyne Farmer). arXiv, Journal of Economic Dynamics & Control, forthcoming, Publisher
When there are increasing returns to investment, there may be multiple locally optimal diversified portfolios.

Long-run dynamics of the U.S. patent classification system (with Daniel Kim). Journal of Evolutionary Economics, forthcoming. Open access at PublisherData.
Patent classification systems change frequently and reflect the dynamics of technological change

Early identification of important patents: design and validation of citation network metrics, with Manuel Mariani and Matúš Medo, Technological Forecasting and Social Change, forthcomingPublisher. 
A citation network-based indicator, time rescaled PageRank, can be used to detect important patents a few years only after that they are granted.

How well do experience curves predict technological progress? A method for making distributional forecasts (with Aimee G. Bailey, Jan D. Bakker, Dylan Rebois, Rubina Zadourian, Patrick McSharry, and J. Doyne Farmer), Technological Forecasting and Social Change  128, pp 104-117, 2018. arXiv, Publisher, Data.
We test and apply a simple method to make distributional forecasts for technological progress conditional on the growth of experience.

How predictable is technological progress? (with J. Doyne Farmer), Research Policy 45(3), 647–665, 2016.   Open access at PublisherData.
We test and apply a simple method to make distributional forecasts for technological progress.

Self-organisation of knowledge economies, Journal of Economic Dynamics and Control 52, 150-165, 2015. Publisher.
The structure of agents-ideas networks depends on the innovation/diffusion trade-off.

Work in progress

The impact of experience on cost: Comprehensive evidence from World War II as a natural experiment (with Diana Greenwald and J. Doyne Farmer)
During WWII, the demand for weapons was not driven by prices. Yet to some extent faster growth of experience was associated with faster productivity improvements.

Disruptive technologies and regional innovation policy (with Pantelis Koutroumpis)

Automation and bottlenecks in occupational mobility: a data-driven network model (with R. Maria del Rio-Chanona, Penny Mealy, Mariano Beguerisse, J. Doyne Farmer)

The origins of new technological domains (with Vilhelm Verendel and J. Doyne Farmer)

PhD Thesis

The evolution of knowledge systems, 2014, Maastricht University Press. PDF

Resting working papers

The size of patent categories: USPTO 1976-2006 (2014), UNU-MERIT WP #2014-060. Updated as “Long-run dynamics of the U.S. patent classification system”, with Daniel Kim.

Learning and the structure of citations networks (2012), UNU-MERIT WP #2012-071. Partly published as “Self-organization of knowledge economies”, and updated as “Knowledge diffusion and the structure of citations networks”, 2014.