动态量化空间均衡模型的理论进展与中国应用

Dynamic Quantitative Spatial Equilibrium:Literature Review and Application in China

量化空间均衡是研究新发展格局和区域协调发展等中国重大议题的有力工具。相比于传统的实证方法或理论模型方法,其优势在于具备一般均衡效应,可进行丰富的反事实模拟和政策分析,匹配多维度数据并实现量化研究。近年来,随着量化空间均衡在多领域的深入应用和交叉融合,这一研究范式呈现出“动态化”拓展的重大特征。动态量化空间均衡模型可应用于宏观经济学、金融经济学、环境经济学、房地产经济学等多个研究领域,拓展了这些领域的研究范式和研究视角。本文首先对动态量化空间均衡文献进行综述,详细梳理和讨论了现有理论框架、技术难点和研究议题;进一步地,将这一框架应用于中国宏观经济的空间动态模拟,展示了建模、算法、数据匹配和模拟等过程,分析了空间均衡视角为传统宏观范式提供的理论启示,以及为构建新发展格局提供的政策含义;最后,展望了动态量化空间均衡在诸多中国本土问题上的广阔应用前景。

In recent years,quantitative spatial equilibrium models(QSM)have been rapidly developed and popularized.Compared with traditional empirical and theoretical methods,QSM’s advantage lies in the general equilibrium effect,based on which we could proceed abundant quantitative counterfactual analysis and policy simulations.In addition,by match multi-dimensional data,QSM is able to contribute rich and credible quantitative analysis.With the interdisciplinary applications of QSM,this research paradigm is incorporating the feature of dynamics.There are at least three necessities for dynamic quantitative spatial equilibrium models(DQSM).First,for some economic disciplines,dynamic frameworks have long been the fundamental paradigm,such as contemporary macroeconomics and financial economics.Second,for some research objects,their own attributes naturally include intertemporal characteristics,such as real estate with durability and investment attributes,and education migration that affects intergenerational mobility.Third,for some events,the evolution process may be slow,resulting in different short-term and long-term impacts,such as the cost-benefit consideration of infrastructure construction,and the long-term and shortterm impacts of environmental changes.Currently,there have been literature reviews on QSM.However,for DQSM,to the best of the author’s knowledge,no literature has given a comprehensive and detailed review.In addition,the application of DQSM among Chinese academia has not yet officially started.This paper attempts to fill these two gaps.This paper firstly outlines the theoretical framework of DQSM,including labor dynamics,capital dynamics,firm dynamics,and other modules.Secondly,this paper explains the key difficulties in introducing spatial dynamics,and points out that the“curse of dimensionality”caused by the interaction of spatial and temporal dimensions in numerical simulation is the main technical difficulty.Thirdly,this paper reviews the application topics of DQSM.We find that DQSM has long ceased to be an exclusive research tool in the three fields of regional economy,urban economy and international trade.It has shown strong applicability in macroeconomics,development economics,financial economics,environmental economics,real estate economics,and other disciplines.Then,as an application illustration,this paper applies DQSM to China’s macro-economy,which not only gives a detailed demonstration of modeling,algorithm,data matching,and simulation,but also proposes new perspectives and new discoveries given by this new framework.It is found that the convergence rate of the economic system drops significantly after the introduction of population migration.In addition,the economic system does not necessarily change monotonically during the dynamic process of converging to a steady state.These findings challenge the typical macro-paradigm which relies on the analysis of the steady-state(or balanced growth path).In a further step,this paper finds that it is not capital accumulation but population distribution that ultimately determines the economic structure.With the gradual agglomeration of the population,the allocation efficiency of labor will be improved,and the level of per capita income will demonstrate regional convergence.The corresponding policy implication is that China should get rid of its over-reliance on physical capital investment,and in the context of the gradual dissipation of the“demographic dividend”,the“new demographic dividend”should be stimulated by improving the allocation efficiency of labor,especially by guiding the population to gather in the advantageous areas.Finally,as a conclusion,this paper discusses the broad application prospects of DQSM in various China’s major domestic economic topics,such as the construction of the national unified market as well as the new development pattern,broad macro-development issues,housing price divergence,and“carbon-peak/carbon-neutrality”goals.