Patents and R and D at the Firm Level: A First Look
This is a first report from a larger study of inventive activity of U.S. firms and some of its consequences. It reports on the relationship between patents applied for and R&D expenditures based on data for 121 large corporations covering the 1968-1975 period. The main conclusion is that there is a statistically significant relationship between a firm's R&D expenditures and the number of patents it applied for and receives. This relationship is very strong in the cross-sectional dimension (squared partial correlations of .8 or higher). It is weaker in the within-firm time-series dimension (partial r[squared]'s of .2 to .3). Attempts to fit an unconstrained distributed lag relationship yields only significant coefficients for the first and last terms in the lag structure, indicating both a quick response of patenting to changes in R&D and a small but persistent effect of past R&D, the truncation of this long lag being reflected in a significant coefficient for R&D lagged five years. In spite of these difficulties, patent counts do measure something systematic and hence are worthy of further study.
PR published as Pakes, Ariel and Zvi Griliches. "Patents and R and D at the Firm Level: A First Report." Economics Letter, No. 5, (1980), pp. 377-381. Number 0561