存在收入差异的社会保障制度选择——基于一个内生增长世代交替模型

社会保障制度选择是经济协调发展中的重要课题。本文建立了一个考虑存在收入差距的异质性个体的内生增长世代交替模型,综合考察了社会保障制度选择对经济增长和收入再分配的影响。分析表明,现收现付制对稳定状态的经济增长率有负面影响,但其收入再分配功能对提高社会总福利存在正向作用,通过数值模拟发现当收入差距较小时,现收现付制对经济增长的抑制作用较强,随着收入差距的拉大,收入再分配功能将逐渐居于主导地位,其综合效应可以改善社会福利。在一定的收入差异程度范围内,存在一个使社会福利最大化的最优现收现付制比率。基于对中国实际的分析,本文认为我国未来的社会保障制度改革应该注重发挥现收现付制的再分配功能。     

中国养老保险体系改革的福利经济学分析

本文用一个福利经济学框架推导出在社会福利最大化目标下现收现付制和基金制混合的养老保险体系的最优混合比率 ,模型中考虑了收入分配的因素 ,模型对过往研究中已有的结论进行了扩展 ,显示当一国的工资增长率和人口增长率之和大于投资报酬率 ,或者 ,当收入差距较大时 ,采用现收现付制有益于整个社会福利的改善。用这一框架分析中国的养老保险体系 ,并结合中国养老保险体系改革的特点 ,得出的结论是在当前及今后相当长的时间内 ,以现收现付制为主的体系可以作为中国养老保险体系的选择。文章进一步分析了现收现付制在中国持续运行的空间及其面临的挑战 ,指出这一制度的可持续运行最终取决于劳动生产率和产出的水平及增长     

社会保障筹资模式的路径选择——基于筹资模式的储蓄效应研究

随着人口老龄化的加剧,许多实行现收现付制社会保障制度的国家财政负担越来越重,为了保证社会保障制度的可持续性,各国开始寻求新的社会保障筹资模式。在世界银行主推的基金制社会保障制度浪潮下,二十世纪90年代开始,中国结合本国实际情况也开始了社会保障制度的改革,并于1997年开始实施社会保险基金的＂部分基金制＂,即现收现付制与完全基金制相结合的筹资模式。本文阐述了现收现付制和基金制的运行机理并探讨了其与储蓄的关系,并在此基础上,对我国的部分基金制进行解析。本文认为部分基金制的＂个人账户＂的储蓄功能目前无法得到实际发挥,由于我国目前的经济条件和收入差距悬殊等问题,使得部分基金制向完全基金制的转变应循序渐进,现收现付方式还应是我国目前实行的部分基金制中的侧重部分。     

公共年金制度的效果--运用内生增长模型分析

本文运用导入外部效应的内生增长模型和叠代模型，分析了社会保障制度中不同财政运行方式的年金制度对经济增长率以及社会福利所产生的效果。得出的结论是，不同的年金制度会通过影响个人的生涯可支配收入而对经济增长和社会福利产生不同的影响。由于完全基金方式的年金制度不改变个人的生涯可支配收入，因此具有中性。但是，现收现付的年金制度却有可能改变个人的生涯可支配收入，从而对经济增长率和社会福利产生负面影响。     

养老金:现收现付制和基金制的比较

养老金：现收现付制和基金制的比较李绍光（中国社会科学院研究生院）从融资方面来说,养老金计划存在着两种制度安排,一种是现收现付制,另一种是基金制。在经济理论中,大部分文献主要沿着再分配效应和经济增长效应这两条线索,对这两种制度安排进行比较与分析。本文拟...     

遗产税、民生财政与中国经济结构转型

文章运用拓展的迭代模型分析了征收遗产税用于社会保险、教育等民生领域对宏观经济、产业结构和社会福利的影响.研究表明:(1)当遗产税补贴积累型社会保险时为完全中性.(2)在补贴现收现付制社会保险和教育时会减少储蓄、提高老年消费、降低代际财富转移;如果补贴教育或和收入关联的现收现付制,还将推动教育的上升并且前者的影响更大.(3)遗产税收入具有“拉弗曲线特征”.(4)实证检验除证实上述结论外还表明相对于补贴现收现付制,在遗产税收入补贴教育时更有利于实现“稳增长、调结构、促消费”这三个重要的宏观经济管理目标,并大大减少社会福利损失.在存在计划生育时,经济增长率更高,社会福利损失将更小;在生育率内生时,遗产税将推动生育率恢复,但对劳动力供给的影响存在不确定性.     

中国城镇基本养老保险的改革效应研究——基于个人账户规模的分析

本文应用经典的迭代模型和新古典经济增长模型分析了在由现收现付制向个人账户与社会统筹账户相结合的混合模式转变过程中,考虑隐性负债的条件下,个人账户规模对于制度转轨的影响。并结合目前中国改革动向,进行了简要的政策评价。分析表明,经济动态无效时,个人账户规模对于各代财富,收入再分配和经济增长具有负效应,并且这种在各代产生的负效应是单调的,从而导致转轨过程最终仍向现收现付制回归。如能妥善处理巨大的隐性负债,建立有效的激励约束机制,中国目前的改革能够实现预期目标。     

不同生育率情形下养老保险筹资模式比较研究

理论研究普遍认为,基金制养老保险筹资模式优于现收现付制,但这几乎都是基于人均资本视角的判断。本文在外生和内生生育率两种情形下,从福利经济学视角分析基金制是否完全优于现收现付制。理论模型表明,在一定参数组合下,无论外生生育率还是内生生育率,都存在使现收现付制下社会福利高于基金制下社会福利的养老保险缴费率。模型的数值模拟显示,存在使现收现付制下社会福利更高的养老保险缴费率,且在外生生育率下（符合我国生育政策）现收现付制缴费率在12%左右社会福利最高,内生生育率下（符合发达国家生育政策）现收现付制缴费率在6%左右社会福利最高。前一数值与已有研究成果观点相近(我国社会统筹部分缴费率应下降到15%左右),后一数值与美国（62%）、日本（77%）等发达国家现收现付制养老保险缴费率相近。稳健性检验显示,只要参数赋值在合理范围内,数值模拟主要结论不变。本文为降低现行我国社会统筹部分养老保险缴费率提供了理论借鉴。     

社会保障税与社会保障制度优化

社会保障税是指定用于社会保障的工薪税。本文分析了工薪税的税收归宿和劳动供给弹性的影响。当劳动供给弹性较小时 ,税收主要由劳动力负担 ,而且可能会增加就业压力 ;工薪税在劳动同质程度较高时可以取得较好的再分配效应。本文还描述了社会保障制度优化的理论过程。社会保障制度优化是指现收现付计划和强制储蓄计划的最优搭配 ,它以“黄金律”条件下的隔代帕累托改进为标准。就同代收入再分配而言 ,将收入再分配计划的目标定为提高受益人的受教育水平 ,而不是直接为其提供免费的社会福利 ,将有助于缓解收入再分配的代价。     

社会保障制度调节收入差距的国际比较及启示

改革开放以来,在中国经济持续高速增长的同时,收入差距扩大问题日益凸显。规范收入分配秩序,完善收入分配调控机制和政策体系是调节收入差距的着力点。社会保障制度是政府调节收入差距、追求社会公平的重要政策工具。美国和瑞典是发达国家市场导向型社会保障制度和福利型社会保障制度的典型代表,对比两种不同社会保障制度调节收入差距的效果,并探讨其收入再分配效应产生差异的原因,总结其社会保障制度调节收入差距的成效和经验,有助于我国通过规范收入分配秩序、完善社会保障制度调节收入差距。     

Fertility,Intra‐Generational Redistribution,and Social Security Sustainability

Incorporating heterogeneity in preference to having children into an overlapping generations model of a small open economy, we examine the effects of changes in the size of pay‐as‐you‐go (PAYG) social security on fertility choices of individuals and population growth of the economy. It is shown that PAYG social security will raise population growth by increasing the number of individuals who have children and the number of children parents have if the system involves redistribution between retirees with different contributions, whereas, if it has no redistribution, PAYG social security does not affect the fertility decisions of individuals.     

Parental nurturing and adverse effects of redistribution

This paper suggests that if parental nurturing is a dominating force in human capital formation then income redistribution may not promote economic growth. In particular, if, consistently with empirical evidence, parental human capital complements investment in a child’s education and yields increasing returns in the intergenerational production of human capital, income redistribution may have an adverse impact on the growth rate of average human capital. Redistribution shifts resources towards the less educationally-productive families and thus in the presence of credit markets imperfections and increasing returns, it reduces the aggregate level of investment in human capital. Moreover, if the degree of increasing returns is sufficiently large to produce sustained growth, this adverse effect on human capital formation may outweigh the conventional beneficial effects of redistribution that arises from the interaction between a production technology exhibiting diminishing returns and credit market imperfections.     

Temptation and social security in a dynastic framework

We investigate welfare and aggregate implications of a pay-as-you-go (PAYG) social security system in a dynastic framework in which individuals have self-control problems. The presence of self-control problems induces individuals to save less because of their urge for temptation towards current consumption. Individuals' efforts to balance between the short-term urge for temptation and the long-term commitment for consumption smoothing result in self-control costs. In this environment PAYG social security works as a self-control cost reducing device. In contrast, the presence of altruism induces individuals to save more. This in turn mitigates the adverse effects of self-control problems and PAYG social security on savings but magnifies the self-control costs. We find that in our environment the adverse welfare effects of a PAYG system are further mitigated relative to the environments that incorporate altruism and self control issues separately. However, the level of mitigation is quite modest.     

Social Security Systems,Human Capital,and Growth in a Small Open Economy

We consider a small open economy in which the level of public education funding is determined by popular vote. We show that growth can be enhanced by the introduction of pay‐as‐you‐go pensions even if the growth rate of aggregate wages falls short of the interest rate. The reason is that the pay‐as‐you‐go (PAYG) system allows future retirees to partially internalize positive externalities of public education due to the positive effect of higher future labor productivity on their pension benefits. The majority support for education funding will be especially strong when the PAYG benefit formula is flat, i.e., progressively redistributive. If a flat benefit PAYG pension system is in place then the economy will achieve the highest growth rate relative to the alternative pension system designs. While such PAYG pension system may be opposed by the majority of working individuals due to inferior returns to their pension contributions relative to a funded scheme, it is likely to be politically sustained by a coalition of older individuals and lower income workers.     

Shifting from pay-as-you-go to individual retirement accounts: A path to a sustainable pension system

With aging demographics and generous pension programs, the sustainability of the pay-as-you-go (PAYG) public pension system has been often questioned and has motivated policymakers to enact reforms in many countries. Although mandatory funded Individual Retirement Accounts (IRAs) appear to be a solution to this unsustainable system, existing reforms usually take place within the PAYG system by reducing pension benefits. This paper evaluates the effects of PAYG reforms as well as reforms that switch to the IRA system. Our analysis shows that PAYG reforms outperform IRA reforms in many aspects. In fact, PAYG reforms achieve higher GDP and yield higher welfare in the long run. The transition to the steady state is also found to be less volatile for PAYG reforms. While PAYG generally places a larger burden on future generations, the positive welfare effect of cross-subsidization dominates the welfare loss. Our findings may explain why pension reform is a controversial issue in most countries and why we rarely observe a shift to the IRA system.     

中国传统文化信念、人力资本积累与家庭养老保障机制

本文首先构建一个人力资本积累模型,考察传统文化信念驱动下的家庭养老保障机制以及社会养老保障制度对家庭养老和人力资本投资行为进而对经济增长的影响。分析表明,传统文化信念将后代人力资本积累与父代养老保障有机地联系起来,提供了一种很好的家庭养老保障和人力资本内生积累机制;现收现付型社会养老保障制度不利于人力资本积累和经济增长。其次,本文以我国现实数据为基础进行实证研究,得到结论是社会养老保障制度对我国人力资本积累和经济增长具有明显的抑制作用,而家庭养老保障机制的良好运转则有助于更好地促进人力资本积累和经济增长。因此,我国在致力于完善社会养老保障制度的同时,决不能忽视家庭养老保障机制的作用与培育。     

An alternative approach to aggregate surplus analysis

This paper suggests a dual to the many-person applied welfare economics problem with constraints on lymp-sum redistribution. The dual has the property of minimizing an aggregator function over individual income transfers. The properties of the aggregator are dependent upon the resource costs of redistribution and not upon the distributional preferences embodied in the social welfare function. An interpretation of the dual problem in terms of consumer surplus is offered.     

Risk management of pensions from the perspective of loss aversion

This paper studies two interrelated questions. First, is a pay-as-you-go (PAYG) pension component beneficial from a risk management point of view? Second, does optimal risk management of old-age consumption differ between different income groups? The analysis is based on so-called lexicographic loss aversion preferences. Interest in these preferences stems from the fact that they explain the cross-section of individuals' savings and asset allocation choices better than alternative models. I find that all income groups benefit from the presence of a substantial PAYG component. Only for the two highest income quintiles old-age provision should heavily rely on equity investments.     

The Impact of Individual Health Account Scheme on Lifetime Income Redistribution: Evidence from China

This paper investigates the effects of a combination of individual health accounts (IHAs) and catastrophic insurance on lifetime income redistribution by examining the variations in end‐of‐life IHA balances and lifetime out‐of‐pocket health expenditures. We exploit longitudinal health expenditure data from 2005 to 2007 in Kunshan City, Jiangsu Province of China. We find a high concentration of low IHA balances at the end of life, with most equal to zero. This finding suggests that most IHA balances are used for health expenditures and that the income redistribution effect through the accumulation of IHA balance is limited. However, the results also show a wide variation in lifetime out‐of‐pocket spending in the form of deductibles and coinsurance, which implies serious inequality in individual financial burden that can lead to a large income redistribution effect.     

现收现付制与人口老龄化关系定量分析

中国目前的养老保险和医疗保险实行的是基金积累制为主的筹资模式。按照有关文献的解释 ,这是因为中国正面临着人口迅速老龄化的压力 ,现收现付制不能有效应对人口老龄化 ,而基金积累制则不存在这一问题。本文构造了一个模型 ,详细分析了现收现付制与人口老龄化的关系 ,给出人口老龄化是否导致现收现付制发生支付危机的定量判别条件 ,并根据人口学相关理论和人口资料预测了 2 0 0 1— 2 0 60年中国人口老龄化趋势 ,从而检验了人口老龄化是否引发现收现付制的支付危机 ,同时给出了现收现付制度下养老金缴费率和人均养老金水平增长率的确定原则。