Firm Size and R&D Intensity: A Re-examination.

Using data from the Federal Trade Commission 's Line of Business Program and survey measures of technological opportunity and appropriability conditions, this paper finds that overall firm size has a very small, statistically-insignificant effect on business unit R&D intensity when either fixed industry effects or measured industry characteristics are taken into account. Business unit size has no effect on the R&D intensity of business units that perform R&D, but it affects the probability of conducting R&D. Business unit and firm size jointly explain less than 1 percent of the variance in R&D intensity; industry effects explain nearly half the variance. Copyright 1987 by Blackwell Publishing Ltd.