INDUSTRIAL RESEARCH AND DEVELOPMENT, INTANGIBLE CAPITAL STOCKS, AND FIRM PROFIT RATES

Cross sectional analysis of firm profitability to determine whether firm investments in research and development (R&D) are a source of above-average returns. Accounting profit rates are adjusted to take account of firm capital outlays on R&D and advertising (i. e. , investments in intangible capital). Then, with the use of a structure-performance regression model, these adjusted profit rates are regressed on various determinant variables including a measure of the firm's stock of R&D capital. This analysis indicates that firms in research-intensive industries earn significantly above-average returns on their R&D capital. These results are robust to alternative assumptions concerning depreciation rates and other model specification changes.