The 50th Anniversary of the Solow Growth Model
回顾索洛增长模型50年来的影响与演变，该模型将增长理论从模糊的稳定性争论转变为分析储蓄、人口、折旧和技术进步等关键问题的灵活框架，并催生了众多扩展与争议。
‘A Conibution to the Theory of Economic Growth’ by Robert M. Solow, published in February 1956, 1 is among the most influential and revered articles in economic theory. The essay—along with its ‘growth-accounting’ companion the following year 2 —transformed growth theory from arguably obscure debates about stability and gloomy knife-edge properties into a fully fledged, flexible framework for analysing key growth questions: e.g. the impact of changes in savings, population, depreciation, and technical progress on the level and growth of output; the nature of transition to steady states; the possibility of convergence and catch-up between countries; etc. Fifty years on, the ‘Solow growth model’ is still at the heart of modern growth theory. But of course, nothing stays still, not least economic theory. In the meantime there have been numerous extensions made to the model and many controversies heaped upon it. Typical examples include incorporating endogenous technical progress and human capital; accounting for the role of externalities, entrepreneurship, and institutions; non-linear aspects; optimal savings decisions; the importance of factor substitution; improvements in product variety and innovation; technology diffusion; and so on and on. Notwithstanding, however, one might even say that criticisms of the Solow growth model are best understood through the lens of the Solow growth model!