收入差距、政府干预与经济增长质量

【作者】 刘宇；

【导师】 张军；

【作者基本信息】 复旦大学 ， 西方经济学， 2009， 博士

【摘要】 收入差距问题往往与社会公平和正义联系在一起,然而,收入差距问题同样具有丰富的效率含义,一旦意识到这一点,经济发展过程中的很多困惑也许都将迎刃而解。从现代经济学的视角出发,任何宏观经济现象都是微观经济主体面对环境约束时努力最大化自身效用的集合产物,收入差距作为微观主体进行最优决策时一个重要的环境约束参数,其变化会通过改变个体决策来实现对整体经济绩效的影响。然而,直到Kuznets(1955)提出著名的收入差距-经济增长倒U型曲线为止,经济学家都还主要从规范的角度看待收入差距问题。Kuznets(1955)开创了收入差距问题效率含义研究的先河,但此后相当长一段时期,人们对收入差距与经济增长关联性的理解仅仅停留在经济发展会改变收入分配格局这样的单向认识上,直到宏观经济学的研究方法在上世纪80年代后逐渐从凯恩斯式总量函数模式转向基于微观主体最优决策基础上的宏观变量决定因素分析这一范式后,收入差距问题的研究方向才出现了重大的转变,这也许是因为人们终于发现了,收入分配格局正是微观主体最优决策时一个重要的约束条件。此后出现了大量讨论收入差距对经济增长效应的经典文献,这些文献从各个角度出发提出了收入差距影响经济增长的机制和渠道,现在,谈到经济增长,收入分配已经成为不可或缺的考虑要件了。然而,不得不指出的是,在国外这一波研究收入差距效率含义的大潮中,经济增长速度成为度量效率的唯一指标,对于发达国家来说,这当然有其合理性,因为不管经济增长的动力是来自于要素投入还是来自于技术进步,最终都将反映在增长速度上,而从长期视角出发,经济增长速度与经济增长持续能力也可以等而论之。但是,对于发展中国家来说,把收入差距与经济增长速度直接联系起来的做法则可能会带来误导,因为特定时期的经济增长速度与经济增长持续能力可能会出现背离的现象。对于中国而言,相比一时的经济增长速度,经济增长的持续能力显然具有更加重要的意义。然而,尽管中国呈现扩大趋势的收入差距水平确实激发了对收入差距问题的极大关注,但是,对中国收入差距问题的研究还主要集中在测算收入差距水平和解释形成原因这一方向上,对收入差距效率含义的研究不多,仅有的一些效率方面的研究也都只是采取实证研究方法对收入差距与经济增长速度进行的计量检验,缺乏对收入差距影响宏观经济绩效机制和渠道的理论分析,更缺少从经济增长持续能力视角出发对收入差距效率含义所作的研究。然而在成功实施改革开放并保持了30年经济快速增长的中国,经济能否持续增长已经成为最受关注的一个问题,不断扩大的收入差距是否会成为中国未来经济持续增长的障碍成为一个自然的疑问。基于上述原因,本文以经济增长持续能力为效率评价指标,从理论层面系统分析了中国收入差距对经济持续增长能力的效应和作用机制,并且采用1988-2001年间的省级面板数据进行了实证检验。本文的主要工作包括:1.从经济持续增长能力的角度定义了经济增长质量,在此基础上研究了收入差距对经济增长质量的效应和作用机制。与此前对经济增长质量的各种定义均不同,本文对经济增长质量的定义包括了技术进步和经济增长模式两个维度。其中经济增长模式以要素投入增加速度与生产率提高速度的比例关系来度量,如果要素投入增加速度与技术进步(生产率)速度不匹配,要素投入增加速度过快,那么虽然技术进步和要素投入的增加共同推动了经济高速增长,但经济增长过程中要素边际产出难以保持在合理水平,增加了未来经济增长不可持续的风险。正是从这个意义上讲,一定时期经济增长速度与经济增长质量会发生背离情况,因此,仅用经济增长速度判断收入差距效率含义就可能会出现误解。2.基于对中国现实特征的观察,本文原创性构造了一个讨论中国收入差距-技术进步效应的数理模型。与现有国外讨论收入差距效率含义的经典模型相比,本文的模型存在两个最重要的区别,第一,本文模型明确区分了不同性质的收入差距,分别就其对技术进步的效应和影响机制进行了分析。而在国外经典模型中,收入差距被隐含地视为禀赋差异基础上市场竞争的自然结果,尽管禀赋差异确实是收入差距的重要原因,但是现实中各种制度性因素导致的有偏收入分配也是收入差距的另一个主要来源。由于不同性质收入差距对微观个体的激励存在重大差别,例如,禀赋性收入差距会激励人们积累人力资本,而制度性收入差距则会产生寻租激励,因此,不加区分地对收入差距问题做效率上的判断同样可能会带来误解。第二,国外讨论收入差距效率问题的经典模型并没有把政府视为具有独立偏好的行为主体,其对收入差距效率问题的讨论基本上是通过微观主体面对一定市场环境进行人力资本或者物质资本投资最优决策的方法展开,尽管有些模型的传导机制也是税率,但税率并不是由具有独立偏好的政府所决定,而是来自微观个体的公共选择过程,因此,国外经典模型实际上排除了政府主动行为对收入差距之于效率影响机制的作用。然而关于中国经济增长的一系列研究均表明,经济上的财政分权体制和政治上的向上负责体制形成了对地方政府干预经济的双重激励,政府行为将改变市场决策参数,对收入差距和技术进步间的效应具有潜在重要影响,更重要的是,由于收入差距通常会改变消费需求,而一旦收入差距降低了总需求,渴望增长的地方政府将会采取更加积极的干预行为来刺激经济规模的扩大,因此,政府干预行为本身不仅会改变收入差距作用于技术进步的机制,同时也可能直接构成机制链条上的重要一环,基于此,本文的模型包含了具有独立偏好的政府,以分析政府干预行为的效应。3.采用1988-2001年间的省级面板数据实证检验了城乡收入差距对技术进步、技术效率、全要素生产率以及经济增长模式等效率变量的效应。就我们所了解的情况,迄今为止国内还没有从收入差距这一视角出发对技术进步或者全要素生产率进行的实证研究。本文的主要结论包括:1.制度性收入差距与技术进步之间可能存在一条类似收入差距与经济增长之间关系的倒U型曲线关系,即在经济发展早期阶段,制度性收入差距有利于技术进步,而当经济发展达到一定阶段后,制度性收入差距将阻碍技术进步。这一结论可以被看作是Kuznets收入差距-经济增长倒U型曲线的一个机制上的理论支持。2.禀赋性收入差距对技术进步的效应存在两个可能性,依据劳动边际成本曲线的位置而定,与现有文献强调税收必将损害人们工作积极性从而对经济增长不利不同,本文的分析表明适当情况下提高税收反而会刺激工作努力程度,从而提高宏观经济绩效。3.收入差距的变动将通过需求效应和劳动供给效应影响技术进步路径,在经济开放状态下,收入差距对需求总量和需求结构的改变会通过劳动供给机制对技术进步发生作用。因此,需求变动的背后往往是劳动供给决策的变化,如果认识不到这一点,政府按照需求进行的调控将可能会起到反面作用。4.政府干预行为改变了不同行业的效率参数,从而也改变了收入差距对技术进步发挥效应的经济环境,依据政府干预行为对行业效率参数的具体效应,政府干预行为可以放大收入差距对技术进步的效应,也可以减弱收入差距对技术进步的效应。5.实证结果显示1988-2001年间,城乡收入差距促进了技术进步,但却同时推动了经济增长模式的粗放化。政府在这一时期的干预行为损害了技术进步,但是由于对效率的促进以及对要素投入的挤出效应,却是有利于经济增长模式的去粗放化。更多还原

【Abstract】 Income inequality is always linked to the concept of unfairness or unjustice, however, it also means much to the economic growth. From the perspective of modern economics, any macroeconomic phenomena are the collective product of the decision made by those individuals faced by constraints when the decision is made to maximize their own utility. As an important environmental constraints parameter, the change of income inequality will surely achieve the overall impact on economic performance by changing the individual’s decision-making. However, until Kuznets (1955) raised the well-known inverted U-curve between the economic growth and income inequality, most economists mainly regard the issue of income disparity as a normative problem. While quite a long period of time since Kuznets (1955), people’s understanding of the relevance between the income gap and economic growth merely keeps the one-way style that economic growth will impose influence on the income distribution. Until the macro-economic research methods turn from total function models of Keynesian-style to the micro-optimal decision-making models in the last century 80’s, the research perspective changes significantly to the opposite direction. Since then, a lot of discussions focus on the effect of income inequality on the economic growth. Now, when we talk about growth, the income inequality has become an inevitable factor taken into consideration.However, it must be pointed out that in this wave of research in foreign countries, the speed of economic growth became the only measure of efficiency. For developed countries, which of course has its own rationality, because no matter how the engine of economic growth come from factor inputs or from the technological progress, it will eventually be reflected in the growth rate. From long-term perspective, the speed of economic growth and sustainability of economic growth can also be of one thing. For developing countries, directly linking the income gap to the economic growth speed may mislead our understanding of this issue. Because in specific period of time, the speed of economic growth and sustainability of economic growth may deviate from each other.For China, compared to the speed of economic growth, the sustainability of economic growth is clearly more important. In spite that the expansion of income inequality indeed stimulated many researches in this field, however, these researches mainly focused on the measurement of the gap level and the interpretation of the formation of the gap. Few research consider the efficiency meaning of the income gap, and only use empirical research methods to test the relation between the income gap and the speed of economic growth, almost no research pay attention to the theoretical analysis of the impact mechanisms and channels between macro-economic performance and the income inequality. Scarcity of the analysis of impact mechanisms between the sustainability of economic growth and the income inequality is much more serious. For these reasons, this paper, using the sustainability of economic growth as indicators for the efficiency, focuses on the theoretical analysis of the effect mechanisms between income gap and China’s sustained economic growth. after theoretical analysis, an empirical test with a database from 1988 to 2001 will also be performed..the main efforts In this paper include:1. Defining the quality of economic growth from the perspective of the capacity of sustainability of economic growth, which is different from prior definition of the quality of economic growth.2. Based on the observation of the characteristics of China’s realities, this paper originally structure a mathematical model to discuss the effect of income inequality on technological progress. Compared to those existed classical model, our model in this paper has two important distinctions. First, the model in this paper makes a clear distinction between the different kind of the income inequality classified by nature, and the effects of each kind on technological progress are analyzed respectively. Second, the existed classical model does not look upon the government as the actors with independent prefer, however, a series of studies on China’s economic growth have shed light on that the fiscal decentralization and political institutions stimulate local government to intervene in the economy to a great extend. Based on this, our model include the analysis of government with independent preferences in order to analyze the effects of government’s intervention.3. Using data between 1988 and 2001 to test the effect of the urban-rural income inequality on the technological progress, technical efficiency, total factor productivity and efficiency of economic growth mode.The main conclusions of this paper include:1. There may exist an inverted U-curve between institutional income inequality and the technological advances which is similar to the inverted U-curve depicting the relationship between economic growth and the income inequality. That is, in the early stages of economic development, the institutional income inequality is in favor of technological progress, but when the economic development reached a certain stage, the institutional income gap will hinder technological progress. This conclusion can be seen as a mechanism to support the Kuznets inverted U-curve.2. The effect of endowment income inequality on technological advances has two possibilities, depending on the condition of marginal labor cost. Different from the existing literature’s argument that the tax will harm the enthusiasm of people to work and so will do harm to the economic growth, this paper’s analysis shows that, sometimes, increasing taxes will stimulate work effort, thereby enhancing the macro-economic performance. 3. The demand effect mechanisms and the labor supply mechanisms are the two main channels through which the income inequality influences the path of technological progress. In an open economy, behind the change of domestic consume demand is often the decision-making change in labor supply. If we do not recognize this point, the government’s intervention would be likely to play a negative role in accordance with the requirements of the demand regulation4. Government’s intervention has changed the efficiency parameters of different industries, leading to a reallocation of resources in the inter-industry. Depending on the specific effect of government’s intervention on different industries, expansion of the scale of short-term outputs maybe accompanied by a wide range of possibilities of the effects on the technological progress.5. The empirical results show that between 1988 and 2001, the income gap between urban and rural areas has promoted technical progress, but at the same time promoting a extensive economic growth model. During this period,the government’s intervention undermines the advances in technology, but because of the efficiency of investment promotion as well as crowding-out effect, it is in favor of a intensive growth pattern.更多还原