Procyclical Labor Productivity and Competing Theories of the Business Cycle: Some Evidence from Interwar U.S. Manufacturing Industries
研究两次世界大战期间美国十个制造业行业中顺周期劳动生产率（短期劳动报酬递增）的来源，发现该现象普遍存在且模式与战后相似，并认为在大萧条并非由技术冲击引起的假设下，这些证据与真实商业周期理论不一致。
Each of the main explanations of procyclical labor productivity, or short-run increasing returns to labor (SRIRL), is closely associated with a competing theory of the business cycle: Real business cycle theorists attribute SRIRL to procyclical technological shocks, proponents of recent theories based on non-convexities believe that SRIRL reflects true increasing returns, and Keynesians favor a labor hoarding explanation. Thus evidence on the sources of SRIRL may be important for discriminating among alternative theories of the cycle. This paper studies the sources of SRIRL in a sample of ten interwar U.S. manufacturing industries. Our main findings are that SRIRL was common in the interwar period and that the pattern of SRIRL across industries was similar to that observed in the postwar period. we argue that, under the presumption that the Depression was not caused by large negative technological shocks, these findings are inconsistent with the technological shocks hypothesis and provide evidence against real business cycle theory in general. we propose tests for discriminating between the increasing returns and labor hoarding explanations but find that our conclusions differ by industry.