Computerized Machine Tools and the Transformation of U.S. Manufacturing
研究了20世纪中期计算机化机床的普及如何影响美国制造业，发现暴露程度高的行业劳动生产率提高但生产岗位减少，工人转向非金属制造业，工会成员受影响较小。
Abstract The diffusion of computerized machine tools in the mid-20th century was a pivotal step in the century-long process of factory automation. We build a novel measure of exposure to computer numerical control (CNC) using initial variation in tool types across industries and differential shifts toward CNC by type. Industries more exposed to CNC from 1970–2007 increased labor productivity and reduced production employment. Workers in more exposed labor markets adjusted by shifting from metal to non-metal manufacturing. Union members were shielded from this job loss, and some workers returned to school to retrain.