This study explores the interaction between private and public physical capital accumulation within a Lewis development framework, in which public infrastructure is subject to congestion. The model shows that when both levels of capital are relatively low, a crowding-out of private investment creates the necessary conditions for the emergence of a development trap, from which a surplus labor economy, if left to the free play of its structural forces, may never escape. Once caught in such a trap, the economy can potentially be released through a big push of public or private capital or a sufficiently balanced combination of both.

中文翻译：

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刘易斯开发框架中的社会开销公共基础设施

本研究探讨了刘易斯发展框架内私人和公共物质资本积累之间的相互作用，其中公共基础设施受到拥堵的影响。该模型表明，当两个资本水平都相对较低时，私人投资的挤出为发展陷阱的出现创造了必要条件，剩余劳动力经济如果任其结构性力量自由发挥，就会陷入发展陷阱。可能永远无法逃脱。一旦陷入这样的陷阱，经济就有可能通过公共或私人资本的大力推动或两者充分平衡的结合而得到释放。