World War II and Convergence
利用二战对各国资本存量的破坏作为工具变量，估计出生产率增长向长期路径趋同的速度约为每年4%至6%，远高于传统认知。
Proxies that measure the effect of World War II on a country's capital stock are used as instruments for estimating standard cross-country growth regressions. The war's destruction should offer a natural experiment that allows us to consistently estimate the speed at which productivity growth converges to its long-run path. This paper presents evidence that convergence rates are approximately 4% to 6% per annum, substantially larger than conventional wisdom. © 2002 by the President and Fellows of Harvard College and the Massachusetts Institute of Technology