Social and Private Rates of Return from Industrial Innovations*

I. Introduction, 221.—II. The sample of innovations, 222.—III. Estimation of social benefits: product innovations used by firms, 222.—IV. Parallel innovative efforts, time horizon, and rates of return, 226.—V. Product innovations used by households, 229.—VI. Process innovations, 231.—VII. Social and private rates of return, 233.—VIII. Factors associated with the gap between social and private rates of return, 235.—IX. Unemployment, repercussions on other markets, and future changes in technology, 238.—X. Conclusion, 239.