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 multi-region model of economic growth with human capital and negative externalities in innovation

We use a multi-region model and provide the first theoretical analysis of the effects of human capital use and a particular kind of innovative activity on economic growth. In each of the N heterogeneous regions in our model, consumers have constant relative risk aversion preferences, there are negative externalities in innovation, and there are three kinds of manufacturing activities involving the production of blueprints for inputs or machines, the inputs or machines themselves, and a single final good for consumption. Our analysis generates four salient findings. First, for each of the N regions, we define a balanced growth path equilibrium, we characterize the market clearing factor prices, and we determine the free entry condition in the R&D sector. Second, we show that without growth in human capital, there is no sustained economic growth in any of the N regions. Third, we show that human capital growth generates sustained economic growth in each of the N regions. Finally, when discussing the above three findings, we shed light on the spatial dimensions of economic growth in our multi-region aggregate economy.     

Factor Saving Innovation

It has been argued that concave models exhibit less “endogeneity of growth” than models with increasing returns to scale. Here we study a simple model of factor saving technological improvement in a concave framework. Capital can be used either to reproduce itself, or, at some additional cost, to produce a higher quality of capital, which requires less labor input. If better quality capital can be produced quickly, we get a model of exogenous balanced growth as a special case of ours. If, however, better quality capital can be produced slowly, we get a model of “endogenous growth” in which the growth rate of the economy and the rate of adoption of new technologies is determined by preferences, technology and initial conditions. Moreover, in the latter case, the process of growth is necessarily uneven, exhibiting a natural cycle with alternating periods of high and slow growth. Growth paths and technological innovations also exhibit dependence upon initial conditions. The model provides a step toward a theory of endogenous innovation under conditions of perfect competition. Journal of Economic Literature Classification Numbers: O30, O40, D92, C61, D24, D41.     

Pollution and life expectancy: How environmental policy can promote growth

This article investigates the influence of environmental policy (EP) on growth in an AK-type growth model, when finite lifetime is introduced and the link between pollution and life expectancy (through the detrimental impact of pollution on health) is taken into account.Using an overlapping generations model à la Blanchard [Blanchard, O. (1985). Debt, deficits and finite horizon. Journal of Political Economy, 93:223-247], we demonstrate that finite lifetime introduces a “generational turnover effect” which modifies the influence of the EP on growth. Thus, when lifetime is finite and independent from pollution, we show that the “generational turnover effect” limits the detrimental impact of the EP on growth, if agents smooth their consumption over time. When pollution negatively influences life expectancy through health, we demonstrate that the “generational turnover effect” is magnified and that the EP and growth have an inverted U-shaped relationship in the steady-state. In this case, we show that the environmental policy is more likely to promote growth (i.e. it stimulates growth for a wider range of environmental taxes) when the impact of pollution on health is important and/or public expenditures in health are low. Finally, using numerical simulations, we find that for the value of parameters that we have chosen, the EP will be more likely to promote growth when agents smooth consumption over time.     

Corruption in a neoclassical growth model with a non-convex production function

In this article, we analyze the bureaucrats’ corruption problem in a simple neoclassical growth model with a non-convex production function. In this model, we consider direct relations between product (income) taxation and corruption, and between corruption and public goods provision. As the main result, we show that the optimal consumption growth path in this economy is higher in a non-corrupt environment than in a corrupt environment and the higher the proportion of corrupt bureaucrats, the higher the cost of corruption to society.     

An empirical study of firm productivity growth based on the dynamic selection model: Effects on the recent decline in Korean exports

Export and productivity growth in the Korean manufacturing sector have both been slow since 2011. To understand this relationship, we examine the productivity distributions of manufacturing firms in Korea by applying the dynamic selection model developed by Sampson (2016). The fitness of the dynamic selection model suggests that a slowdown in the market selection mechanism may be a crucial contributor to the stagnant growth in the productivity. In addition, we find that the productivity difference between exporting firms and non-exporting firms has decreased and the low productivity growth of firms exporting to non-foreign affiliates has contributed to this trend.     

Economic development and financial depth in a model with costly financial intermediation

According to Gurley and Shaw, economic development typically is accompanied by a transition from self-financed to intermediated investment activity. In their account, economic growth stimulates financial market development, and financial market development is a strong contributing factor in enhancing real growth. We model the co-evolution of the real and financial sectors during the growth process. To do so, we embed a role for liquidity provision into a conventional neoclassical growth model. Following Baumol and Tobin, we also introduce a fixed cost associated with “trips to the bank”. We describe conditions under which the development of a financial system may or may not proceed smoothly. When it does not, development traps are observed. We also discuss policy interventions that may reduce the potential for development traps to arise.     

A contribution to the theory and empirics of Schumpeterian growth with worldwide interactions

This paper proposes an integrated theoretical and methodological framework characterized by technological interactions to explain growth processes from a Schumpeterian perspective. Global interdependence implied by international R&D spillovers needs to be taken into account in both the theoretical and empirical models. For this task, spatial econometrics is the appropriate tool. The econometric model we propose includes the neoclassical growth model as a particular case. We can therefore explicitly test the role of R&D investment in the long-run growth process against the Solow growth model. Finally, the properties of our spatial econometric specification allow the explicit evaluation of the impact of home and foreign R&D spillovers.     

教育、创新与经济增长

由于知识的非竞争性,基于R&D的内生增长模型存在规模效应,即人口数量越大,从事R&D的人员越多,经济增长率越快。本文将R&D人员创新活动的有效时间引入知识的积累方程———“点子”生产函数,发现OECD国家科学家和工程师数量增加伴随着R&D人员创新活动的有效时间的减少,二者相互抵消,使得TFP增长率保持不变。通过校准理论模型,本文模拟了49个国家的经济增长率,发现模型对经济增长率跨国数据的解释能力明显强于Lucas模型和Romer模型。如果利用模型对跨国经济增长率的模拟值与真实值之间的残差平方和来评判模型的优劣,则本文模型对Lucas模型和Romer模型至少分别改进了20%和59%。     

绿色创新与经济增长动态关系研究——基于VAR模型的实证分析

基于湖北省1993—2018年相关数据,运用VAR模型对绿色创新与经济增长的动态关系进行实证研究,同时将绿色创新分为发明专利授权和实用新型专利授权两个要素。研究发现,经济增长与发明专利授权、实用新型专利授权存在长期协整关系;发明专利授权对经济增长存在“扩散效应”,实用新型专利授权对经济增长先体现“扩散效应”,后体现“挤出效应”,而经济增长对两者均具有“扩散效应”;发明专利授权对经济增长的促进作用明显大于实用新型专利授权对经济增长的促进作用。因此,应积极构建绿色创新与经济增长的长效互动机制;加大绿色创新开发投入,完善绿色创新相关制度;提升绿色创新的投入效率,加速绿色创新成果转化率。     

An endogenous growth model with embodied energy-saving technical change

In this paper, we extend the Romer [Journal of Political Economy 98 (Part 2) (1990) S271] model in two ways. First we include energy consumption of intermediates. Second, intermediates become heterogeneous due to endogenous energy-saving technical change. We show that the resulting model can still generate steady state growth, but the growth rate depends negatively on the growth of real energy prices. The reason is that real energy price rises will lower the profitability of using new intermediate goods, and hence, the profitability of doing research, and therefore have a negative impact on growth. We also show that the introduction of an energy tax that is recycled in the form of an R&D subsidy may increase growth. We conclude that in order to have energy efficiency growth and output growth under rising real energy prices, a combination of R&D and energy policy is called for.     

Is Declining Productivity Inevitable?

Fertility has been declining on all continents for the last couple of decades and this development is expected to continue in the future. Prevailing innovation-based growth theories imply, as a consequence of scale effects from the size of population, that such demographic changes will lead to a major slowdown in productivity growth. In this paper we challenge this pessimistic view of the future. By allowing for endogenous human capital in a basic R&D driven growth model we develop a theory of scale-invariant endogenous growth according to which population growth is neither necessary nor conductive for economic growth.     

History’s a curse: leapfrogging, growth breaks and growth reversals under international borrowing without commitment

A simple open-economy AK model with collateral constraints accounts for growth breaks and growth-reversal episodes, during which countries face abrupt changes in their growth rate that may lead to either growth miracles or growth disasters. Absent commitment to investment by the borrowing country, imperfect contract enforcement leads to an informational lag such that the debt contracted upon today depends upon the past stock of capital. The no-commitment delay originates a history effect by which the richer a country has been in the past, the more it can borrow today. For (arbitrarily) small delays, the history effect offsets the growth benefits from international borrowing and dampens growth, and it leads to both leapfrogging in long-run levels and growth breaks. When large enough, the history effect originates growth reversals and we connect the latter to leapfrogging. Finally, we argue that the model accords with the reported evidence on changes in the growth rate at break dates. We also provide examples showing that leapfrogging and growth reversals may coexist, so that currently poor but fast-growing countries experiencing sharp growth reversals may end up, in the long-run, significantly richer than currently rich but declining countries.     

Output Variability and Economic Growth: the Japanese Case

We examine the empirical relationship between output variability and output growth using quarterly data for the 1961–2000 period for the Japanese economy. Using three different specifications of GARCH models, namely, Bollerslev's model, Taylor/Schwert's model, and Nelson's EGARCH model, we obtain two important results. First, we find robust evidence that the “in‐mean” coefficient is not statistically significant. This evidence is consistent with Speight's (1999) analysis of UK data and implies that output variability does not affect output growth. In other words, this finding supports several real business cycle theories of economic fluctuations. Second, we find no evidence of asymmetry between output variability and growth, a result consistent with Hamori (2000) .     

R&D-expenditure in an endogenous growth model

The aim of this paper is to analyze the role that aggregate R&D-expenditure plays in economic growth. We introduce a technology of innovation based on expenditure that generates endogenous sustainable growth in absence of any scale effect. This R&D-model permits us to study the effects of some fiscal policies. In particular, we analyze how subsidies to R&D-investment and physical capital accumulation affect the long-run growth rate. For the empirical cross-country analysis we directly derive a structural econometric model.     

转型期知识产权保护制度的增长效应研究

知识产权保护制度是发展中国家能否克服短期技术困境、促进经济长期增长的关键因素。本文从宏观层面研究我国知识产权保护制度对经济增长的影响机制,主要贡献在于:首先通过构建知识产权保护指数,实际测算1985—2010年中国的知识产权保护程度。其次通过构建"知识—生产"两部门理论模型,分析知识产权对经济增长的影响机制。最后基于中国转型期经验数据,运用动态建模方法实证研究我国知识产权制度对经济增长的影响。研究表明,对于处于转型期的中国而言,短期内较弱的知识产权保护程度有利于经济增长,而较强的知识产权保护程度则有碍于经济增长;在长期均衡的状态下,较强的知识产权保护程度确实可以促进经济增长。     

The effect of labor market monopsony on economic growth

In this endogenous growth model, a minimum efficient scale of production and workers’ home-to-work travel costs combine to give firms monopsony power, and this monopsony power leads to slower growth. Monopsony drives the wage below the marginal product of labor. This lower wage leads to lower investment in human capital and thereby to a lower growth rate. This makes investment in human capital – and therefore the growth rate – suboptimal. We provide evidence from a cross-country panel to support our model: Urbanization, which we assume is determined by a country’s exogenous population density and cropland area, positively impacts the wage share of output; the wage share positively impacts educational attainment; higher-income countries have higher wage shares; and within-country upticks in the wage share have a positive lagged effect on the growth rate.     

A “Managerial” trade union and economic growth

By setting up a simple Romer-type [Romer, P.M., 1989. Capital accumulation in the theory of long-run growth. In: Barro, R.J. (Ed.), Modern Business Cycle Theory. Harvard University Press, Cambridge, MA] endogenous growth model embodying a political trade union (rather than the traditional economic labor union), this paper explores the effects of unionization on unemployment, growth and welfare by highlighting the essence of internal conflict within the union. It is shown that the conflicting interests between the leadership and membership within the union play a decisive role in the unemployment, growth and welfare effects of unionization. Given the fact that taxation is another potential candidate besides unions in explaining the poor performance of a macro-economy, we re-examine the taxation effects within the growth model with equilibrium unemployment caused by the presence of the trade union and compare our findings with those for the traditional full-employment growth model. In general, we find that the taxation effects of income and consumption crucially depend not only on the institutional arrangements for taxing unemployment benefits, but also on the way the government budget is balanced.     

Be productive or face decline. On the sources and determinants of output growth in Italian manufacturing firms

This article investigates the sources and determinants of output growth of Italian manufacturing firms. Applying stochastic frontier techniques, we decompose output growth into factor accumulation and TFP growth for the period 1998–2003. TFP growth is further decomposed into technological change, efficiency change and scale effects. Two key results emerge from the analysis. After confirming that both input accumulation and TFP growth are important in explaining output growth, we show that efficiency change (technological catch-up) is the most significant component of TFP growth in explaining output growth distribution. Furthermore, using a specific model of the asymmetric error component, we find that R&D spillovers, banking efficiency and public infrastructures have statistically significant and economically relevant effects on technological catch-up.     

Population dynamics and utilitarian criteria in the Lucas–Uzawa Model

This paper introduces population growth in the Uzawa–Lucas model, analyzing the implications of the choice of the welfare criterion on the model's outcome. Traditional growth theory assumes population growth to be exponential, but this is not a realistic assumption (see Brida and Accinelli, 2007). We model exogenous population change by a generic function of population size. We show that a unique non-trivial equilibrium exists and the economy converges towards it along a saddle path, independently of population dynamics. What is affected by the type of population dynamics is the dimension of the stable manifold, which can be one or two, and when the equilibrium is reached, which can happen in finite time or asymptotically. Moreover, we show that the choice of the utilitarian criterion will be irrelevant on the equilibrium of the model, if the steady state growth rate of population is null, as in the case of logistic population growth. Then, we show that a closed-form solution for the transitional dynamics of the economy (both in the case population dynamics is deterministic and stochastic) can be found for a certain parameter restriction.