Identifying the age profile of patent ci
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Aditi Mehta; Marc Rysman; Tim Simcoe
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Article
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2009
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John Wiley and Sons
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English
β 281 KB
## Abstract Previous research studies the age profile of patent citations to learn about knowledge flows over time. However, identification is problematic because of the collinearity between application year, citation year, and patent age. We show empirically that a patent's βcitation clockβ does n