When is market incompleteness irrelevant for the price of aggregate risk (and when is it not)?

In a standard incomplete markets model with a continuum of households that have constant relative risk aversion (CRRA) preferences, the absence of insurance markets for idiosyncratic labor income risk has no effect on the premium for aggregate risk if the distribution of idiosyncratic risk is independent of aggregate shocks and aggregate consumption growth is independent over time. In equilibrium, households only use the stock market to smooth consumption; the bond market is inoperative. Furthermore, the cross-sectional distributions of wealth and consumption are not affected by aggregate shocks. These results hold regardless of the persistence of idiosyncratic shocks, even when households face tight solvency constraints. A weaker irrelevance result survives when we allow for predictability in aggregate consumption growth.     

Undiscounted optimal growth with consumable capital and labor-intensive consumption goods

This paper presents a complete characterization of the optimal policy in a two sector undiscounted growth model. The model is an extension of the Leontief two sector model, which analyzes the optimal allocation of capital and labor to a consumption good sector and an investment good sector. The paper extends this framework to include consumable capital. Thus, the planner has preferences over the consumption good and the consumable capital. Future welfare levels are treated equally as current ones. Geometric techniques are applied to characterize the optimal policy if the consumption good is labor-intensive. The results suggest that if the initial capital stock is above a threshold level, that depends upon the consumption of capital, every optimal program is monotonic, converges to the golden rule stock in a finite number of periods, and undergoes either unemployment or excess capacity of capital.     

Are lifecycle funds appropriate as default options in participant-directed retirement plans?

Since the enactment of Pension Protection Act of 2006, lifecycle funds that reduce exposure to stocks with age have rapidly replaced money market funds as the most commonly nominated default investment options for participant-directed retirement plans. We examine their appropriateness in meeting a threshold level of retirement wealth required by plan participants. Using a utility function motivated by prospect theory (Kahneman and Tversky, 1979), we show that whilst lifecycle funds are vastly superior to money market funds (except for very low thresholds), they rank below balanced funds that maintain constant exposure to equities over time. As thresholds increase, lifecycle funds are also dominated by funds that switch assets conditional to prior investment performance. Even in the absence of a minimum threshold wealth level, lifecycle funds do not emerge as the most preferred choice among the investment options considered by our paper.     

A股投资对居民财产性收入贡献不足及其解释

股票已是中国居民主要的财富之一,股票投资也理应成为居民财产性收入的重要来源之一。通过股票投资增加居民财产性收入,有利于居民收入多元化和扩大消费需求,转变经济增长方式。但是,中国股票市场存在低投资回报率、低现金分红比率、高市盈率和偏高的市场风险等现状,弱化了股票投资对居民财产性收入的贡献。实证研究也表明股票投资收益率、现金分红同居民财产性收入、社会零售商品总额相关性不够显著。股票市场投资增值功能缺失、上市公司治理机制不完善、股票投资主体的不成熟和股票市场投资工具单一化是造成股票投资对居民财产性收入贡献不足的主要原因。为了发挥股票市场的投资和分散风险功能,应在扩大股票市场规模的同时,明确股票市场的投资功能和定位,完善股票市场的发行机制,优化投资主体结构,加强发行主体和投资主体的培育建设。     

The effects of longevity and distortions on education and retirement

This article studies the impact of longevity and taxation on life-cycle decisions and long run income. Individuals allocate optimally their total lifetime between education, working and retirement. They also decide at each moment how much to save or consume out of their income, and, after entering the labor market, how to divide their time between labor and leisure. The model incorporates experience–earnings profiles and return to education function that follows evidence from the labor literature. In this setup increases in longevity raises the investment in education—time in school—and retirement. The model is calibrated to the US and is able to reproduce observed schooling trends of the last century. It also reproduces the increase in retirement, as the evidence shows. Simulations show that a country equal to the US but with 20% smaller longevity will be 25% poorer, mostly because of the impact of life expectancy on human capital formation and retirement. In this economy labor taxes have a strong impact on the per capita income, as it decreases labor effort, time at school and retirement age, in addition to the general equilibrium impact over physical capital.     

Nonseparable preferences and optimal social security systems

In this paper, we consider economies in which agents are privately informed about their skills, which evolve stochastically over time. We require agents' preferences to be weakly separable between the lifetime paths of consumption and labor. However, we allow for intertemporal nonseparabilities in preferences like habit formation. In this environment, we derive a generalized version of the Inverse Euler Equation and use it to show that intertemporal wedges characterizing optimal allocations of consumption can be strictly negative. We also show that preference nonseparabilities imply that optimal differentiable asset income taxes are necessarily retrospective in nature. We show that under weak conditions, it is possible to implement a socially optimal allocation using a social security system in which taxes on wealth are linear, and taxes/transfers are history-dependent only at retirement. The average asset income tax in this system is zero.     

Labor supply of elderly people,fertility, and economic development

Increases in life expectancy and the fertility rate have been observed as per-capita income increases in economically developed countries with high per-capita income. We explain these observations using a synthetic economic model with endogenous lifetime, retirement, and human capital accumulation. In contrast to the result obtained by assuming an institutionally fixed and compulsory retirement, a longer life expectancy attributable to rises in per-capita income can induce elderly people to leave the labor market later, thereby enabling them to increase consumption of goods as well as “children” when young. Consequently, higher per-capita income can be associated with higher fertility.     

从生产力不平衡结构看我国宏观经济波动

从投资角度看,高端部门的资本有机构成和劳动生产率比低端部门要高很多,在一定的投资下,高端部门会有更大的产出或利润。因此,在市场经济条件下投资自然会向高端部门倾斜和集中,其结果将形成产品或产业结构的不平衡增长,从而引起人们收入结构的不平衡增长。从消费角度看,人们在收入增长以后,会努力满足较高层次的需求。如果存在不同收入结构,这种倾斜最先出现在高收入阶层,这一现象又会渐次对其他各收入阶层产生“示范效应”。简言之,不同收入阶层人口的消费结构会先后出现对高端部门产品的倾斜,当然,消费的这种倾斜将受到低收入阶层的收入水平、人口规模的影响,最终将影响高端部门的增长。     

Optimal labor income taxation in a two-sector dynamic general equilibrium model

This paper presents a new approach to the two-sector optimal taxation problem. We derive the optimal labor income tax rate which depends on factor intensity across sectors. It is the labor intensity that determines the initial wage rate, and therefore the optimal labor tax rate. We show that an increase in the initial relative price of consumption goods decreases the optimal tax rate on labor income in the case that the consumption goods sector is capital-intensive while it increases the optimal tax rate on labor income in the case that the investment goods sector is capital-intensive.     

Heterogeneity in Ability and Inheritance,Disparities, and Development

This paper investigates the impact of income inequality on economic growth. A two-period overlapping generations model is developed where agents are heterogeneous in innate abilities and inheritance. In the first period, they receive their inheritance and their abilities are revealed. There are only two types of abilities: high and low. Individuals decide on their education level, and divide their inheritance between spending on education and saving. In the second period, individuals supply their labor and allocate the labor income and the return to their saving between consumption and bequests to their offsprings. Initial capital stock is owned entirely by the capitalists. In this context, a more equal distribution of income enhances economic growth if the economy is lower than a threshold capital-labor ratio, while income inequality has an insignificant effect above this threshold. The predictions of the model are tested empirically using the Hansen (1999) threshold estimation. The results, using a panel of 70 countries for the period 1971-1999, suggest that there is a statistically significant threshold income per capita, below which the coefficient on the relationship between inequality and economic growth is significantly negative and above which the estimate is not significant.     

Investment horizons,cash flow news,and the profitability of momentum and reversal strategies in the Chinese stock market

This study investigates the profitability of momentum and reversal strategies of different investment horizons in the Chinese stock market. The findings indicate that momentum strategies are profitable for investment horizons less than one week. For longer investment horizons, reversal strategies are profitable. This result is very different from the US market, where profitable momentum strategies yield to much longer investment horizons. We show that this is because investors in Chinese stock market generally overreact to the company cash flow news while investors in US market underreact to cash flow news.     

刍议中国劳动力价格与经济增长路径转变

改革开放以来,中国经济取得了令世人瞩目的成就,与此同时,经济运行中不和谐的因素也日益增加.投资和消费的比例关系失衡,表现为投资率偏高而消费率偏低.从劳动者收入入手研究投资、消费比例问题,在研究中国劳动力价格的现状后得出结论:相对于居民生活密切相关的粮价、油价、水电费、通讯费、教育费、医疗费来说,中国劳动力价格太低,因此,提高劳动力价格,增加其收入才是破解投资消费失衡的"密钥",也是促进中国经济从依赖投资的增长方式向依靠消费拉动经济增长方式的增长路径转变的"治本之道".     

A NOTE ON “A ONE‐SECTOR NEOCLASSICAL GROWTH MODEL WITH ENDOGENOUS RETIREMENT”: EXISTENCE OF MULTIPLE STEADY STATES*

This note extends Matsuyama's 0–1 endogenous retirement choice model to the framework with continuous endogenous retirement choice to study the consumption‐saving decision and capital accumulation in an overlapping generation model. The conditions for the existence of multiple steady states have been derived. In contrast to the 0 or 1 labour choice, the partial retirement may be a stable steady state under the continuous endogenous retirement choice in the second period. And this implies that partial retirement may be a stable optimal choice. Also, we find that the retirement choice depends on the initial capital stock when there are multiple steady states.     

Labor market shocks and retirement: Do government programs matter?

This paper argues that labor market conditions are an important and often overlooked determinant of retirement transitions. In our analysis, we examine how the unemployment rate affects retirement and whether the Social Security (SS) system and Unemployment Insurance (UI) system influence how older workers respond to labor market shocks. We use pooled cross-sectional data from the March Current Population Survey (CPS) in our analysis. We find that downturns in the labor market increase retirement transitions and that the magnitude of this effect is comparable to that associated with moderate changes in financial incentives to retire and to the threat of a health shock facing older workers. Interestingly, retirements only increase in response to an economic downturn once workers become SS-eligible, suggesting that retirement benefits may help to alleviate the income loss associated with a weak labor market. We also estimate the impact of UI generosity on retirement and find little consistent evidence of an effect. This suggests that in some ways SS may serve as a more effective form of unemployment insurance for older workers than UI.     

Adverse selection in credit markets and regressive profit taxation

In many countries, taxes on businesses are less progressive than labor income taxes. This paper provides a justification for this pattern based on adverse selection that entrepreneurs face in credit markets. Individuals choose between becoming entrepreneurs or workers and differ in their skill in both of these occupations. I find that endogenous cross-subsidization in the credit market equilibrium results in excessive (insufficient) entry of low-skilled (high-skilled) agents into entrepreneurship. This gives rise to a corrective role for differential taxation of entrepreneurial profits and labor income. In particular, a profit tax that is regressive relative to taxes on labor income restores the efficient occupational choice.     

Designing social security - a portfolio choice approach

Public social security systems may provide diversification of risks to individuals’ life-time income. Capturing that a pay-as-you-go system (paygo) may be considered as a “quasi-asset”, we study the optimal size of the paygo system as well as the optimal split between funded and unfunded pension saving by means of a theoretical portfolio choice framework. A low-yielding paygo system can benefit individuals if it contributes to hedge other risks to their lifetime resources. Numerical calculations indicate that optimal social security systems should be at least partly paygo financed in many economies. The optimal magnitude of the paygo system depends on the specified risk concept as well as the stochastic properties of stock market returns and implicit paygo-returns.     

The effect on optimal consumption of increased uncertainty in labor income in the multiperiod case

We consider a multiperiod, additive utility, optimal consumption model with a riskless investment and a stochastic labor income. The main result is that for utility functions belonging to the set F, consumption decreases when we go from any sequence of distribution functions representing labor income to a more risky sequence. A concave utility function belongs to F if its first derivative exists everywhere and is convex.     

Stabilization policy and indeterminacy in a small open economy

This paper studies the (de)stabilizing effects of income tax rules in a two-sector small open economy with production externalities. The paper shows that in the model with positive sector-specific externalities in the investment sector and negative sector-specific externalities in the consumption sector (or positive aggregate investment externalities), a regressive income tax rule can stabilize such an economy against indeterminacy, whereas a progressive income tax rule can increase the tendency for indeterminacy to occur. This paper also studies two variants that consider an imperfect world bond market and an endogenous labor supply, respectively, and shows that the qualitative results stated above remain valid. Moreover, increasing the level of sector-specific investment externalities can decrease (increase) the minimal level of tax progressivity required for indeterminacy if the investment externalities are below (above) a certain critical value and if the negative externalities in the consumption sector are taken as given.     

Non-linear causality between the stock and real estate markets of Western European countries: Evidence from rank tests

Using the non-parametric rank tests proposed by Breitung (2001), we set out in this study to determine whether any non-linear long-run equilibrium relationship exists between the stock and real estate markets of Western European countries. We go on to adopt the threshold error-correction model (TECM) to determine whether a similar relationship is discernible possibly non-linear functions of the log-price of these two markets. The findings clearly point to the existence of long-run unidirectional and bidirectional causality between the real estate market and the stock market in regions both above and below the threshold level. Finally, we find the existence of both wealth and credit price effects in the real estate markets and stock markets of Western European countries, which thereby offer financial institutions and individual investors in their construction of long-term investment portfolios within these two asset markets.     

我国劳动收入比重偏低的成因分析——基于劳动力市场的视角

近年来我国劳动收入在初次分配中的比重呈下降趋势。劳动收入比重偏低会对收入分配公平、消费投资平衡和经济增长质量产生负面影响。文章基于劳动力市场的视角对我国劳动收入比重偏低的成因进行了理论研究,并采用我国2000-2011年省级面板数据,构建了一个劳动收入比重决定模型,实证检验了经济发展过程中,二元经济转型和劳动力市场分割对我国劳动收入比重变化的影响。研究结果表明,我国劳动收入比重偏低是二元经济转型的特定发展阶段和劳动力市场分割的制约力量协同作用的结果。在二元经济转型过程中,劳动收入比重的变化趋势呈U型规律。我国劳动收入比重偏低的原因在于,劳动力市场城乡分割和劳动力市场行政垄断行业分割延缓了二元经济转型进程,增加了劳动收入比重在下降阶段的停留时间。因此,稳定我国劳动收入比重的关键是削弱劳动力市场分割,加快二元经济转型。