We incorporate the external effects of capital in production and endogenous technology choice into the standard overlapping generations model. We demonstrate that our model can exhibit a poverty trap, a middle-income trap, and perpetual growth paths. We also show that, under some economic conditions, an economy exhibits all three of these phenomena, depending on its initial capital level, and that the economy caught in the middle-income trap can exhibit chaotic fluctuations in the long run. This is a stark contrast to the result obtained by Umezuki and Yokoo (J Econ Dyn Control 100:164-175, 2019a) that we cannot observe any chaotic fluctuations. Because the model of Umezuki and Yokoo (2019) is a special case of our model in the sense that there is no externality in production, our result means that we need the combination of technology choice and externalities in production to obtain chaotic fluctuations in the standard overlapping generations model with Cobb-Douglas technologies.

我们将资本对生产的外部影响和内生技术选择纳入标准的代际重叠模型中。我们证明，我们的模型可以展示贫困陷阱、中等收入陷阱和永久增长路径。我们还表明，在某些经济条件下，一个经济体会表现出所有这三种现象，具体取决于其初始资本水平，并且陷入中等收入陷阱的经济从长远来看可能会表现出混乱的波动。这与 Umezuki 和 Yokoo (J Econ Dyn Control 100:164-175, 2019a) 获得的结果形成鲜明对比，我们无法观察到任何混沌波动。由于 Umezuki 和 Yokoo (2019) 的模型是我们模型在生产中不存在外部性的意义上的特例，因此我们的结果意味着我们需要将技术选择和生产中的外部性相结合才能获得标准的混沌波动采用柯布-道格拉斯技术的重叠代模型。