← Search Econometrica Vol. 36 No. 1 1968 On the Theory and Measurement of Technological Change C. G. F. Simkin; Murray Brown DOI10.2307/1909621 Volume36 Issue1 Pages206 Sources semanticscholar openalex crossref Cite APA 7 MLA 9 Chicago (author–date) Harvard Elsevier Harvard (JFE, JBF…) The Accounting Review Academy of Management American Marketing Association INFORMS (Management Science) Copy citation Copied ✓