CREST - Labratoire d'Economie Industrielle
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Institutional Affiliation: ENSEA
NBER Working Papers and Publications
|November 2005||Identifying Age, Cohort and Period Effects in Scientific Research Productivity: Discussion and Illustration Using Simulated and Actual Data on French Physicists|
with , : w11739
The identification of age, cohort (vintage), and period (year) effects in a panel of individuals or other units is an old problem in the social sciences, but one that has not been much studied in the context of measuring researcher productivity. In the context of a semi-parametric model of productivity where these effects are assumed to enter in an additive manner, we present the conditions necessary to identify and test for the presence of the three effects. In particular we show that failure to specify precisely the conditions under which such a model is identified can lead to misleading conclusions about the productivity-age relationship. We illustrate our methods using data on the publications 1986-1997 by 465 French condensed matter physicists who were born between 1936 and 1960.
Published: Bronwyn Hall & Jacques Mairesse & Laure Turner, 2007. "Identifying Age, Cohort, And Period Effects In Scientific Research Productivity: Discussion And Illustration Using Simulated And Actual Data On French Physicists," Economics of Innovation and New Technology, Taylor and Francis Journals, vol. 16(2), pages 159-177. citation courtesy of
|March 2005||Measurement and Explanation of the Intensity of Co-publication in Scientific Research: An Analysis at the Laboratory Level|
with : w11172
In order to study networks of collaboration between researchers, we propose a simple measure of the intensity of collaboration, which can be easily interpreted in terms of relative probability and aggregated at the laboratory level. We first use this measure to characterize the relations of collaboration, as defined in terms of co-publication between the scientists of the French "Centre National de la Recherche Scientifique" (CNRS) in the field of condensed-matter physic, during the six-year period 1992-1997. We then use it to investigate the importance of various factors of collaboration: mainly the geographical distance between laboratories, but also their specialization and size, their productivity and the quality of their publications, and their international openness. We find that the...
Published: Antonelli, C., et al. (eds.) New Frontiers in the Economics of Innovation and New Technology: Essays in Honour of Paul A. David. Cheltenham, U.K. and Northampton, MA: Edward Elgar, 2006.