Working Paper: NBER ID: w2457
Authors: Manuel Trajtenberg
Abstract: The goal is to tackle anew the main problems encountered in using patent data in economic research, namely, the large variance in the value of patents, and the difficulties in matching patents with economic categories. The first is addressed with the aid of patent citations, the second with computerized search techniques for large databases. The proposed solutions are applied to the case of Computed Tomography (CT) Scanners, a pathbreaking innovation in medical technology. The main findings are that patents weighted by citations are highly correlated with the value of innovations, and that important innovations generate further innovative activity (R&D), and hence bring about down-the-line patents.
Keywords: patents; citations; innovation; economic research; computational techniques
JEL Codes: O31; O32
Edges that are evidenced by causal inference methods are in orange, and the rest are in light blue.
| Cause | Effect |
|---|---|
| patents weighted by citations (O34) | value of innovations (O35) |
| important innovations (O35) | further innovative activity (O39) |
| important innovations (O35) | downstream patents (O34) |
| patents (O34) | R&D expenditures (O32) |