Patent Policy in an Endogenous Growth Model

We investigate how the patent policy affects economic growth and social welfare based on an endogenous growth model with R&D activities. We show that the patent length that maximizes the social welfare is finite. Moreover, by introducing compulsory licensing, we also show that the patent length that maximizes the social welfare is not infinite even if the royalty rate can be controlled. Received June 29, 2001; revised version received February 5, 2002 Published online: February 17, 2003 We wish to thank two anonymous referees for their constructive comments. We also thank Akira Yakita for his helpful comments.     

Learning-by-doing versus Schooling in a Model of Endogenous Growth

A two sector model of learning-by-doing measured by means of production aggregated over time and of human capital accumulation in a schooling sector is presented. Time utilization is rival between schooling and learning-by-doing. Depending on the sum of elasticities of the accumulated factors (i.e., of production experience and educational human capital) in both sectors, a situation with or without endogenous growth results. Dynamic optimization of the choice between leisure and working and of the division of human capital between education and production is executed. Transitional dynamics are analyzed for a Cobb-Douglas example and a numerical simulation is performed.JEL classification: C61, D90, O41.Acknowledgements The author would like to thank Eric C. Meyer and two anonymous referees for helpful comments. The usual caveats apply.revised version received November 23, 2003     

贸易、环境污染与经济增长——基于开放经济下的一个内生增长模型

通过构建一个开放经济条件下的内生增长模型,文章探讨了国际贸易、环境质量与经济持续增长三者的内在关系以及相互作用的动力机制。首先,通过对模型的竞争性市场均衡分析,给出了平衡增长路径的经济增长率,并系统地分析了在环境污染进入效用函数的情形下长期经济增长的内在机理。其次,通过对最优增长路径进行比较静态分析,分别讨论了贸易自由化对环境质量、经济增长、福利效应的影响;污染外部性对长期经济增长的约束等。最后给出了模型的综合结论及其现实涵义。     

资源约束条件下长期经济增长的动力机制--基于内生增长理论模型的研究

文章通过将存量有限且不可再生的自然资源引入生产函数,构建了一个产品种类扩张型的四部门内生增长模型。首先,通过对模型的市场均衡分析,给出了平衡增长路径的经济增长率以及均衡解存在的一个充分性条件,系统地探讨了在人口增长、自然资源不断耗竭的约束条件下内生技术进步促进长期经济增长的动力机制;其次,通过对平衡增长路径进行比较静态分析,讨论了各经济变量以及经济环境参数的变化对稳态增长率的影响效应及其作用机制,并给出其经济学解释;最后是综合结论及政策涵义。     

A Closed-form Solution of the Uzawa-Lucas Model of Endogenous Growth

This paper presents a closed-form solution to the Uzawa-Lucas endogenous growth model with human and physical capital. Our result also applies if an external effect in the use of human capital in goods production occurs. Using the ``guess-and-verify' method, we determine the two value functions of the social planner in the centralized economy and of the representative agent in the decentralized case. We show that the introduction of income taxes on wages and of a subsidy on physical capital earnings helps the decentralized economy in reaching the social optimum, while keeping the policy maker's budget balanced. Finally, we derive the time-series implications of the model's solution.     

Examination and Approval of New Patents in an Endogenous Growth Model

This study introduces the examination duration for newly developed goods into a standard R&D-based growth model. Producing such goods requires approval from an authority, and their examination incurs both cost and time. Thus, there is a lag between invention and production. This study investigates the effects of reducing the examination duration on examination backlogs (the number of newly invented goods under examination), economic growth, and welfare. We obtain an inverted-U shaped relationship between backlogs and duration, because reducing the duration decreases backlogs by accelerating the examination process, but simultaneously increases backlogs by promoting R&D and increasing the number of applications. In addition, we demonstrate that reducing the examination duration promotes economic growth. However, a rather short examination duration needs considerable resources as the examination has a higher cost. Thus, an extremely short duration hurts welfare. Our numerical analysis reveals the existence of an optimal examination duration.     

The Microeconomics of an R&D-Based Model of Endogenous Growth

This paper explores the microeconomic structure underlying a class of endogenous growth models in which product differentiation and stochastic quality growth coexist. The general equilibrium model generates a stationary stochastic equilibrium in which a nondegenerate ergodic distribution of firm size depends systematically on parameters of the model. Features of the model necessary for stable endogenous aggregate growth are explored, and predictions of the model are compared with microeconometric evidence on R&D intensity, firm growth, and concentration.     

Anticipated Environmental Policy and Transitional Dynamics in an Endogenous Growth Model

This paper makes a new attempt toinvestigate how an anticipatedenvironmental policy governs the transitionaldynamics of an economy when pollutionexternality is taken into account. Themodeling strategy we use is an AK technologyendogenous growth framework with an endogenousleisure-labor choice. It is found that, unlikeinelastic labor supply framework, a rise inpublic abatement expenditure will stimulate thebalanced economic growth rate. It is alsofound that public abatement technology plays animportant role in determining the transitionaladjustment of the economic growth rate inresponse to a pre-announced environmentalpolicy.     

Endogenous Growth Cycles in Continuous Time

The endogenous dynamics of a closed constant returns multi-market economy are examined in which agents face downward sloping demand. The trigger for growth in this model is a technological change that warrants costly adjustment in input quantities by agents. In the resulting dynamic game, relative prices within markets remain constant. Consequently, all own price elasticities are constant. In markets characterized by lower cost of capital the unique outcome is collusion in which agents do not incur adjustment cost and there is no adoption of new technology. But in other markets a unique non-cooperative equilibrium exists in which agents do incur the cost of adopting the new technology. Only three specifications of adjustment costs are feasible. Output increases along an S-shaped time path with or without a non-explosive cyclical component.     

内生城市增长理论模型与实证研究述评

城市增长是现代经济增长理论研究和实证研究的重要内容。城市增长理论可划分为内生城市增长理论和外生城市增长理论。本文重点阐述三个城市内生增长模型即外部性城市增长模型、新经济地理城市增长模型和超边际城市增长模型及其主要思想;围绕“人力资本积累”和“产业聚集”对城市增长的影响,综述相关经验研究;简单总结和评述内生城市增长模型,为进一步研究中国城市增长提供理论借鉴和经验参考。     

Comparison Utility in a Growth Model

We examine the dynamics of two endogenous-growth modelsin which agents have comparison utility. In the inward-lookingeconomy, individuals care about how their current consumptioncompares with their own past consumption. In the outward-lookingeconomy, they care about how their own consumption compares withother peoples consumption. In response to a negative shock tocapital, saving and growth will temporarily fall in both of themodels that we consider but will remain constant in a model withstandard preferences. The decline will be smaller in the outward-than in the inward-looking case, but utility will be lower inthe former case because of a negative externality.     

税收、财政支出与内生经济增长

构建了基于财政支出、税收的内生经济增长模型,并推导出在给定税收、财政支出政策的变化路径时,经济会达到"竞争性分散均衡",税率与经济增长存在"倒-U"型关系,政府投资性支出与经济增长之间正相关。利用中国省际面板数据进行实证检验显示,在我国经济运行中,总产出、消费、投资、政府投资性支出、税率、利息率、工资水平之间存在长期均衡关系。我国宏观税率为28.63%时达到最优值,政府投资性支出对经济增长率存在正向影响,但不同区域间存在较大差异性。     

内生经济增长理论框架下的市场失效与财政政策

内生经济增长理论认为,知识和人力资本的外部效应与创新带来的垄断势力推动经济增长的同时,也会带来非帕雷托最优的经济增长收入分配的不公平,将阻碍经济增长;加快知识和人力资本积累、促进技术进步以及缓解收入分配不公平的财政政策能纠正市场失效,使长期经济增长达到社会最优.     

Exhaustible Resources, Monopolistic Competition, and Endogenous Growth

One of the central analytical findings of the growth literature is that continuous growth is possible even in an economy with exhaustible resources. Based on this result, this paper addresses the question of whether different equilibrium trajectories which lead to a balanced growth path are possible within an endogenous growth model with incomplete competition. Although the Solow-Stiglitz condition is violated due to a monopolistic sector, we nevertheless demonstrate that steady growth in per capita consumption is possible under the condition that the rate of entry of new monopolists exceeds that of the average monopolist's decline in output. As a necessary but not sufficient condition for indeterminacies in a growing economy, this paper demonstrates that the partial production elasticity of capital must be smaller than that of the exhaustible resource.     

Endogenous Growth and Natural Resource Scarcity

Endogenous growth theory has rekindled interest in the role of innovation in determining long-term economic growth. Generally, this body of literature has ignored the contribution of natural resources to growth or the role of innovation in overcoming resource scarcities. The latter problem has been a focus of resource economics for many years, but innovation is usually modelled as exogenous rather than endogenous technological change. Recent investigations in political economy have additionally suggested that the supply of innovation may itself be constrained by resource scarcities, especially in the developing world. The following paper attempts to bridge these theoretical gaps through the formal analysis of two issues: First, a simple Romer-Stiglitz model of endogenous growth with resource scarcity and population growth is developed to determine the optimal balanced growth path for the economy. Second, the basic model is extended to allow for the possibility of resource availability constraining the supply of innovation, so that in the long run innovation net of any resource constraint is zero. However, under the latter conditions it is still possible to avoid resource exhaustion and thus achieve a constant level of per capita consumption in the long run. The paper therefore demonstrates that endogenous growth can overcome resource scarcity, but the outcome in the long run depends critically on assumptions concerning any constraints imposed by resource availability on the generation of innovation.     

Paul Romer: Ideas,Nonrivalry, and Endogenous Growth

In 2018, Paul Romer and William Nordhaus shared the Sveriges Riksbank Prize in Economic Sciences in Memory of Alfred Nobel. Romer was recognized “for integrating technological innovations into long‐run macroeconomic analysis”. This article reviews his prize‐winning contributions. Romer, together with others, rejuvenated the field of economic growth. He developed the theory of endogenous technological change, in which the search for new ideas by profit‐maximizing entrepreneurs and researchers is at the heart of economic growth. Underlying this theory, he pinpointed that the nonrivalry of ideas is ultimately responsible for the rise in living standards over time.     

再论包含两类技术创新的内生经济增长模型

目前关于产品种类扩大型和熊彼特质量改进型的技术创新内生增长模型均较完善,但缺乏同时纳入两类技术变革的内生增长模型。本文构建了包含两类技术创新的内生增长模型,综合分析了技术进步导致经济增长的内在机制,并利用全素生产率核算方法进行了测算。测算发现在1995年至2009年期间政府有意识的技术研发投入对中国经济增长的贡献率上升了12个百分点,但与发达国家相比仍有较大差距,需政府进一步加大研发投入力度,同时加大科技成果转化为经济效益的强度。     

Fiscal Policy and Long-run Growth in R&D-based Models with Endogenous Market Structure

This paper shows that in a model of endogenous growth that does not exhibit the scale effect, taxes on consumption and labor income and the level and composition of public expenditure have no effect on steady-state growth. The only fiscal instruments that affect steady-state growth are taxes on asset and corporate income. In line with standard intuition, tax rates and public expenditure have level effects on income per capita. These results emphasize that although growth is endogenous, in the sense that it is determined by the model and it is subject to policy action, instruments that work by changing market size do not affect it. Effective growth-enhancing policies operate through the interest rate.     

Endogenous distribution and equilibrium growth: a note

Does distributive conflict diminish during the course of economic development? This article outlines a model in which distribution, the tax rate and growth evolve endogenously over time. When voting occurs over a tax on capital, we show that the growth rate is maximized at the political equilibrium in the long run. When voting occurs over a general income tax, we show that the growth rate is maximized at the political equilibrium in both the short and long run. These results suggest that the transitional dynamics of growth models with redistributive politics lead to growth‐maximizing outcomes, as distributive conflict diminishes in the course of development. This implies that the democratic process leads to greater consensus over policy choices, with a perfect convergence of interest across individuals with respect to the tax rate.