Published:
Cambridge, Mass: National Bureau of Economic Research, August 2007
Published in:NBER working paper series ; no. w13338
Extent:
1 Online-Ressource
Language:
English
DOI:
10.3386/w13338
Identifier:
Reproduction note:
Hardcopy version available to institutional subscribers
Origination:
Footnote:
Mode of access: World Wide Web
System requirements: Adobe [Acrobat] Reader required for PDF files
Description:
We examine the home bias of international knowledge spillovers as measured by the speed of patent citations (i.e. knowledge spreads slowly over international boundaries). We present the first compelling econometric evidence that the geographical localization of knowledge spillovers has fallen over time, as we would expect from the dramatic fall in communication and travel costs. Our proposed estimator controls for correlated fixed effects and censoring in duration models and we apply it to data on over two million citations between 1975 and 1999. Home bias declines substantially when we control for fixed effects: there is practically no home bias for the more modern sectors such as pharmaceuticals and information/communication technologies