Industry Equilibrium Dynamics & Theory of Technology Diffusion and Vintage Captial

在过去几年中，出现了大量新的数据集，对这些数据的实证研究侧重于公司的规模分布、营业额（公司的进入和退出）、公司的增长和规模以及公司就业的可变性。该项目的目的是开发经济模型，以严格比较现有行业行为的时间序列和横截面数据。这些模型最终将有助于预测和政策评估。更具体地说，研究者过去的竞争行业分析被扩展到一个动态的随机框架。资本投资决策包括在固定均衡分析中，以便分析经济政策对公司周转率、规模分布和就业可变性的影响。将一般竞争产业动态理论推广到考虑总不确定性和资本积累的情况。该理论提供了一种动态规划算法。该项目还分析了在技术互补性和特定（腻子粘土）资本形式存在的情况下，在一般平衡框架下技术变革的扩散和增长。分析了增长模型的动态特性，重点是了解特定资本的现有分布如何影响新技术的引入；期望在新技术传播中的作用；创新、扩散和增长的共同影响；并建立了组织资本扩散模型。这个项目很重要，因为它填补了产业组织文献的空白。与这一领域的大量实证工作相比，很少有人尝试开发有关行业行为动态的经济模型，这些模型对企业的进入、周转率、退出和规模分布都有影响。研究结果应该为一些极其重要的问题提供新的见解，例如均衡价格、营业额、集中度等如何随着需求的变化或新行业的发展而在一个行业中演变，或者需求变化对一个衰落行业的演变的影响。

During the last few years there has been an explosion of new data sets and empirical studies of these data focused on the size distribution of firms, turnover (entry and exit of firms), growth and size of firms and the variability of firms' employment. The purpose of this project is to develop economic models that can rigorously compare the time series and cross section data on industry behavior now available. These models will ultimately be useful for predictions and policy evaluations. More specifically, past competitive industry analysis by the investigator is extended to a dynamic stochastic framework. Capital investment decisions are included in the stationary equilibrium analysis to permit the analysis of the impact of economic policies on the rate of turnover of firms, size distribution and variability of employment. The general competitive industry dynamic theory is extended to account for aggregate uncertainty and capital accumulation. This theory provides a dynamic programming algorithm. The project also analyzes diffusion of technological change and growth in the presence of technological complementarities and specific (putty clay) forms of capital, in a general equilibrium framework. The dynamic properties of the growth model are analyzed, focusing on understanding how the existing distribution of specific capital affects the introduction of new technologies; the role of expectations in the diffusion of new technologies; joint implications between innovation, diffusion and growth; and a model on the diffusion of organization capital. This project is important because it fills a gap in the industrial organization literature. In contrast to the vast empirical work in this field, there have been very few attempts to develop economic models on the dynamics of industry behavior with implications on entry, the rate of turnover, exit and size distribution of firms. The results of the research should provide new insights into a number of extremely significant issues such as how equilibrium prices, turnover, concentration, etc. evolve in an industry as a consequence of a change in demand or the evolution of new industries or the implications of changes in demand for the evolution of a declining industry.