A Theoretical Study of Macroeconomic Growth and Fluctuations under Competition

本文的研究目的是发展不完全竞争条件下的宏观经济增长与波动理论。我在1995年和1996年进行的研究分为两个领域。第一个是建立一个不完全竞争的中期宏观动态模型，解释真实的工资和就业的决定。近年来，新凯恩斯主义经济学家提出了多种不完全竞争的宏观经济模型。但是，它们大多是短期静态模型，因为它们没有考虑资本积累和技术变革。在本文的研究中，我构建了一个商品市场和劳动力市场都存在不完全竞争的宏观动态模型，分析了资本积累和技术进步对真实的工资和就业的影响。第二个研究是关于R& D的内生增长模型。罗默提出了一个经济增长模型，在这个模型中，技术进步是由R&D活动内生决定的。该模型最有趣的特征是，由于资本品部门的不完全竞争和R&D部门的外部性，均衡增长偏离了最优增长。在本研究中，我从以下两个方面对罗默的模型进行了扩展。首先，分析了模型的过渡过程，这是目前还没有人做过的。第二，将R&D部门的生产函数转化为更符合实际的形式。然后，我发现，“规模效应”，这使得罗默的模型不切实际，并没有出现在我们的模型。

The purpose of this research is to develop the theory of growth and fluctuations of macroeconomy under imperfect competition. The research that I conducted in 1995 and 1996 is divided into two fields. The first one is to construct a medium-term macro dynamic model with imperfect competition that explains the determinations of real wages and employment. Recently, many types of macroeconomic models with imperfect competition were developed by new Keynesian economists. But, most of them are short-run static models in that they do not consider the accumulation of capital and technological changes. In my research, I constructed a macro dynamic model with imperfect competitions both in the commodity market and the labor market, and analyzed the determinations of real wages and employmant, taking into account the accumulation of capital and technological changes. The second of my research is concerned with the endogenous growth model with R&D.P.Romer developed a model of economic growth in which technological progress is determined endogebously by R&D activities. The most interesting character of this model is that the equilibrium growth diverges from the optimal growth due to the imperfect competition in the capital goods sector and the externality in the R&D sector. In my research, I extended Romer's model in the following two respects. First, I analyzed the transitional process of the model, which nobody has done so far. Second, I changed the production function in R&D sector into more realistic form. Then, I found that the "scale effect", which made Romer's model unrealistic, did not appear in our model.