Notes on [[griliches_1990]]

> ... the discovery of a strong relationship between patent numbers and R
> " D expenditures in the cross-sectional dimension, implying that patents
> are a good indicator of differences in inventive activity across different
> firms. While the propensity to patent diffes significantly across industries
> [interesting?], the relationship between R " D and patents is close to
> proportional, especially for firms above a minimal size. [pp. 1701-1702]

> These findings, especially the large amount of skewness in this distribution,
> lead to a rather pessimistic implications for the use of patent counts as
> indicators of short-run changes in the output of R&D. [p. 1702]