a panel of 346 observations from 1975 to 1979
number of observations : 1730
observation : production units
country : United States
A dataframe containing :
Compustat's identifying number for the firm (Committee on Uniform Security Identification Procedures number)
a two-digit code for the applied R&D industrial classification (roughly that in Bound, Cummins, Griliches, Hall, and Jaffe, in the Griliches R&D, Patents, and Productivity volume)
is the firm in the scientific sector ?
the logarithm of the book value of capital in 1972.
the sum of patents applied for between 1972-1979.
the logarithm of R&D spending during the year (in 1972 dollars)
the logarithm of R&D spending (one year lag)
the logarithm of R&D spending (two years lag)
the logarithm of R&D spending (three years lag)
the logarithm of R&D spending (four years lag)
the logarithm of R&D spending (five years lag)
the number of patents applied for during the year that were eventually granted
the number of patents (one year lag)
the number of patents (two years lag)
the number of patents (three years lag)
the number of patents (four years lag)
Hall, Bronwyn , Zvi Griliches and Jerry Hausman (1986) “Patents and R&D: Is There a Lag?”, International Economic Review, 27, 265-283.
Cameron, A.C. and Trivedi P.K. (1998) Regression analysis of count data, Cambridge University Press, http://cameron.econ.ucdavis.edu/racd/racddata.html, chapter 9.
Cameron, A.C. and P.K. Trivedi (2005) Microeconometrics : methods and applications, Cambridge, pp. 792–5.