patrhgh.doc     Last update Nov. 20, 1994        Bronwyn H. Hall
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This is the documentation for the two files patr7079.dat and patr7279.dat.
These files contain data on 346 and 642 manufacturing firms with patents
and R&D spending from 1970 to 1979 and 1972 to 1979 respectively. The 346 
firms are a subset of the 642.  

The data are those used in Hall, Griliches, and Hausman (1986), 
"Patents and R&D: Is There a Lag?", IER 27: 265-283. The selection 
of the firms, and creation of the data are described in Hall, 
Griliches, and Hausman, NBER Technical Working Paper 
No. 72 by Cummins, Hall, Laderman, and Mundy, and Bound, Cummins,
Griliches, Hall, and Jaffe, "Who Does R&D and Who Patents?," in
Griliches, Zvi (ed), R&D, Patents, and Productivity, University of
Chicago Press (1984). 

The files have the same organization, fixed format ~80 column length,
4 records per firm-observation, data separated by blanks, but in fixed
fields so the file can be read either by fixed or free format commands.
The order of the variables is the following:

CUSIP    Compustat's identifying number for the firm (Committee on 
	 Uniform Security Identification Procedures number). 
ARDSIC   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). 
SCISECT  Dummy equal to one for firms in the scientific sector. 
LOGK     The logarithm of the book value of capital in 1972.
SUMPAT   The sum of patents applied for between 1972-1979. 
LOGR70-  The logarithm of R&D spending during the year (in 1972 dollars).
  LOGR79
PAT70-   The number of patents applied for during the year that were 
  PAT79  eventually granted. 

The PATR7279 file has the same variables, but contains only LOGR72-LOGR79
and PAT71-PAT79 (note that the patents start in 1971, not 1972).
Effective October 9, 1999, one value of R&D in 1978 has been corrected in 
this file - thanks to Emmanuel Duguet for pointing out the error.