Year
Compustat identifier for the firm
Two-digit code for the applied R&D industrial classification
Equals 1 if firm in the scientific sector
Logarithm of the book value of capital in 1972
Sum of patents applied for between 1972-1979
Number of (successful) patents applied for this year
Number of (successful) patents applied for lagged one year
Number of (successful) patents applied for lagged two years
Number of (successful) patents applied for lagged three years
Number of (successful) patents applied for lagged four years
Logarithm of R&D spending this year (in 1972$)
Logarithm of R&D spending lagged one year (in 1972$)
Logarithm of R&D spending lagged two years (in 1972$)
Logarithm of R&D spending lagged three years (in 1972$)
Logarithm of R&D spending lagged four years (in 1972$)
Logarithm of R&D spending lagged five years (in 1972$)
= 1 if YEAR = 2
= 1 if YEAR = 3
= 1 if YEAR = 4
= 1 if YEAR = 5