Working Paper: NBER ID: w5712
Authors: Adam B. Jaffe; Manuel Trajtenberg
Abstract: The extent to which new technological knowledge flows across institutional and national boundaries is a question of great importance for public policy and the modeling of economic growth. This paper develops a model of the process generating subsequent citations to patents as a lens for viewing knowledge diffusion. We find that the probability of patent citation over time after a patent is granted fits well to a double-exponential function that can be interpreted as the mixture of diffusion and obsolescence functions. The results indicate that diffusion is geographically localized. Controlling for other factors, within-country citations are more numerous and come more quickly than those that cross country boundaries.
Keywords: No keywords provided
JEL Codes: No JEL codes provided
Edges that are evidenced by causal inference methods are in orange, and the rest are in light blue.
| Cause | Effect |
|---|---|
| patent citations (O34) | knowledge diffusion (O36) |
| geographical localization (R32) | citation frequency (A14) |
| within-country citations (A14) | citation frequency (A14) |
| university patents (O34) | citation frequency (A14) |
| grant year (I23) | citation frequency (A14) |
| institutional nature of assignee (F22) | citation frequency (A14) |
| technological field (O30) | citation frequency (A14) |