A many-person Ramsey tax rule

Define the social marginal utility of an individual's income as the gain to society of a unit of consumption by the individual plus the value of his marginal propensity to pay taxes out of income. This concept rather than the social marginal utility of consumption (equal to the first term above) seems helpful in understanding optimal tax first order conditions. For example, with many consumers (and a poll tax as well as excise taxes) the change in aggregate compensated quantity demanded is proportional to the covariance between individual quantities demanded and social marginal utilities of income.     

Optimal income tax under the threat of migration by top-income earners

We examine how allowing individuals to emigrate to pay lower taxes changes the optimal nonlinear income tax scheme in a Mirrleesian economy. An individual emigrates if his domestic utility is less than his utility abroad, net of migration costs — utilities and costs both depending on productivity. A simple formula, that complements Saez's formula obtained in closed economy, is derived for the marginal tax rates faced by top-income earners. It depends on the labour elasticity, the tax rate abroad and the migration costs expressed as a fraction of the utility obtained abroad. The Rawlsian marginal tax rates, obtained for the whole population, illustrate a curse of the middle-skilled. Simulations are provided for the French economy.     

Envy and Altruism: Contrasting Bivariate and Univariate Prospect Preferences

We compare prospect ordering with and without envy and altruism. We find that envy can induce a violation of the univariate first‐degree stochastic dominance (FSD), and thus a violation of the classic expected utility monotonicity axiom. Surprisingly, altruism can also violate FSD preferences. The intuitive explanation of the result in the case of altruism hinges on the sign of the mixed derivative of the bivariate preference: the individual might prefer a certain correlation between her wealth and her peer group's wealth, and is therefore willing to violate FSD as long as the outcomes of the two parties are ordered according to her preferences. When investments are considered, envy and altruism can distort not only preferences but also actual choices.     

基于公平偏好的信息系统集成知识创新契约设计

基于公平心理客观上对协同主体决策过程的影响,引入F-S公平心理模型,构建了信息系统集成知识创新决策模型。得到结论:对于具有公平偏好心理的原系统服务商而言,其努力水平受嫉妒心理的影响,且随着嫉妒心理程度的提升而降低,道德风险随着努力水平的降低而增大;当原系统服务商付出最优努力水平时,它能有效规避道德风险。     

Smith and Rousseau on envy in commercial societies

Abstract

Several works emphasise the similarities between Rousseau and Smith's analysis of self-interest. We will show, along the lines of Le Jalle, that these similarities end on a divergent appreciation of the importance of envy in commercial societies for, contrary to Rousseau, Smith did not consider envy to be a major threat in commercial societies. Part 1 presents their quite similar definitions of envy based on three characteristics: envy comes from a disadvantageous comparison with others; it is painful and malevolent. Part 2, then, studies their moral psychology, or the way they understand the relationship between sympathy and pity on the one hand, and comparison and envy on the other. Here, we identify significant differences between our two philosophers which might explain why they have opposing views on the predominance of envy in commercial societies and on the issue of inequalities of wealth as we show in Part 3. Rousseau thinks that envy increases with wealth and inequality and thus pervades commercial societies, while Smith sees envy as the exception rather than the rule, and, moreover, does not provide a historical genesis for envy. For Smith, it is emulation rather than envy which is the driving force of the progress of society.     

关于分配的若干有争议问题的看法

在研究我国现阶段分配问题时应该重视研究劳动所得,不应把重点放在非劳动收入上,劳动所得可以通过按劳分配获得,也可以通过按要素分配获得。生产要素按贡献参与分配的原则不等于按生产要素分配,生产要素按贡献参与分配原则中的“贡献”是指对使用价值生产的贡献,不能用分配工作的具体形式的某些共同性模糊不同分配方式的根本区别。     

The assumption of equal marginal utility of income: how much does it matter?

In most applied cost–benefit analyses, individual willingness to pay (WTP) is aggregated without using explicit welfare weights. This can be justified by postulating a utilitarian social welfare function along with the assumption of equal marginal utility of income for all individuals. However, since marginal utility is a cardinal concept, there is no generally accepted way to verify the plausibility of this latter assumption, nor its empirical importance. In this paper, we use data from seven contingent valuation studies to illustrate that if one instead assumes equal marginal utility of the public good for all individuals, aggregate monetary benefit estimates change dramatically.     

Habit formation and indeterminacy in overlapping generations models

I introduce habit formation into an otherwise standard overlapping generations economy with pure exchange populated by three-period-lived agents. Habits are modeled in such a way that current consumption increases the marginal utility of future consumption. With logarithmic utility functions, I demonstrate that habit formation gives rise to stable monetary steady states in economies with hump-shaped endowment profiles and reasonably high discount factors. Intuitively, habits imply adjacent complementarity in consumption, which in turn explains why income effects are sufficiently strong in spite of the logarithmic utility. The three-period horizon further strengthens the income effect.     

Co-monotonicity: Toward a utility function capturing envy

Envy affects economic decisions, and can lead to monotonicity violation. We introduce co-monotonicity—a generalization of monotonicity, expected to hold even in the presence of envy. Experimental results and implications for the form of possible utility functions are discussed.     

INEQUALITY, REDISTRIBUTION, AND RENT-SEEKING

This paper presents a non-median voter model of redistribution in which greater inequality leads to lower redistribution. Bargaining between interest groups and politicians over exemptions implies that individuals with sufficiently high income will not pay taxes in equilibrium. Therefore, voters will set tax rates low enough so as to control the incentives for rent-seeking. An increase in inequality, by putting more income in the hands of individuals that can buy exemptions, will lead to lower equilibrium redistribution. The model can be used to account for a negative relationship between inequality and growth and provides a new explanation of why the poor do not expropriate the rich in democracies.     

The effects of endowment size and strategy method on third party punishment

Numerous experiments have shown that people often engage in third-party punishment (3PP) of selfish behavior. This evidence has been used to argue that people respond to selfishness with anger, and get utility from punishing those who mistreat others. Elements of the standard 3PP experimental design, however, allow alternative explanations: it has been argued that 3PP could be motivated by envy (as selfish dictators earn high payoffs), or could be influenced by the use of the strategy method (which is known to influence second-party punishment). Here we test these alternatives by varying the third party’s endowment and the use of the strategy method, and measuring punishment. We find that while third parties do report more envy when they have lower endowments, neither manipulation significantly affects punishment. We also show that punishment is associated with ratings of anger but not of envy. Thus, our results suggest that 3PP is not an artifact of self-focused envy or use of the strategy method. Instead, our findings are consistent with the hypothesis that 3PP is motivated by anger.     

二元结构、经济转轨与城乡收入差距分化

文章认为,城乡收入差距内生于"经济人"追求自身效用最大化的过程当中,直接套用库兹涅茨-威廉姆森假说对我国的城乡收入差距可能并不一定具有太大的解释力,而将我国的城乡二元结构和经济转轨这一双重制度变迁背景引入城乡差距模型中才能清楚地解释中国的城乡差距。研究发现,人口自由流动条件下,随着经济的发展,城乡收入差距会逐步缩小;人口不自由流动条件下,城乡差距会发生多层分化,但即使如此,中国的城乡差距仍不太符合所谓的库兹涅茨-威廉姆森假说。     

The Marginal Costs and Benefits of Redistributing Income and the Willingness to Pay for Status

The effect of status on aggregate welfare is ambiguous for marginal reforms that redistribute income. If average consumption falls, the change in relative consumption increases household utility but reinforces the decrease in household labor supply, raising welfare cost. For parameterizations of the model developed here, reforms which lower average consumption increase aggregate welfare. Numerical calculations show that status increases marginal welfare cost and marginal net benefit for a demogrant reform. Redistributing to high income households may increase aggregate welfare depending on the definition of average consumption and if the willingness to pay for status increases with income.     

Bivariate almost stochastic dominance

Univariate almost stochastic dominance has been widely studied and applied since its introduction by Leshno and Levy (Manag Sci 48:1074–1085, 2002). This paper extends this construction to the bivariate case by means of suitable two-attribute utility functions. After having confined correlation aversion and correlation loving to some acceptable levels, bivariate almost stochastic dominance rules are introduced for the preferences exhibiting confined correlation aversion and confined correlation loving. The impact of a change in risk in terms of bivariate almost stochastic dominance on optimal saving is analyzed as an application, as well as the effect of envy and altruism on income distributions. Finally, alternative definitions of bivariate almost stochastic dominance are discussed, as well as testing procedures for such dominance rules in financial problems.     

The Aggregation of Climate Change Damages: a Welfare Theoretic Approach

The economic value of environmental goods is commonly determined using the concepts of willingness to pay (WTP) or willingness to accept (WTA). However, the WTP/WTA observed in different countries (or between individuals) will differ according to socio-economic characteristics, in particular income. This notion of differentiated values for otherwise identical goods (say, a given reduction in mortality risk) has been criticized as unethical, most recently in the context of the 'social cost' chapter of the IPCC Second Assessment Report. These critics argue that, being a function of income, WTP/WTA estimates reflect the unfairness in the current income distribution, and for equity reasons uniform per-unit values should therefore be applied across individuals and countries. This paper analyses the role of equity in the aggregation of climate change damage estimates, using basic tools of welfare economics. It shows one way of how WTP/WTA estimates can be corrected in aggregation if the underlying income distribution is considered unfair. It proposes that in the aggregation process individual estimates be weighted with an equity factor derived from the social welfare and utility functions. Equity weighting can significantly increase aggregate (global) damage figures, although some specifications of weighting functions also imply reduced estimates. The paper also shows that while the postulate of uniform per-unit values is compatible with a wide range of 'reasonable' utility and welfare specifications, there are also cases where the common-value notion is not compatible with defensible welfare concepts.     

Optimal consumption and the timing of the resolution of uncertainty

As is well-known, consumers want to accumulate precautionary savings in the face of income risks when their marginal utility is convex (prudence). In this paper, we explore the effect of the timing of the resolution of income uncertainty on savings. An agent faces uncertainty about his income at date t+2. What is the effect of being informed that the uncertainty will be resolved at date t+1 on the consumption at date t? We show that the effect is positive, if and only if, marginal utility is convex (prudence), when either the risk free rate is equal to the rate of pure preference for the present, or when the utility function is HARA. The intuition is that an early resolution of uncertainty allows for time-diversifying the risk. It therefore plays a role similar to a reduction of the income risk, whose effect on savings is negative under prudence.     

Giffen behavior independent of the wealth level

We demonstrate that a well-behaved utility function can generate Giffen behavior, where “well-behaved” means that its indifference curves are smooth, convex, and closed in a commodity space; the resulting demand function of each good is differentiable with respect to prices and income. Moreover, we show that Giffen behavior is compatible with any level of utility and an arbitrarily low share of income spent on the inferior good. This contrasts sharply with the common view that the Giffen paradox tends to occur when households’ wealth levels are low. Comments from Murray C. Kemp, Binh Tran-Nam, Ngo Van Long, Masao Oda, Noritsugu Nakanishi, and Chiaki Hara have greatly improved the paper. We have also benefited from discussions with Koichi Hamada, Satya Das, Takashi Kamihigashi, Tomoyuki Kamo, Toru Kikuchi, Katsufumi Fukuda, Yu-chin Chen, Fahad Khalil, Takeshi Nakatani, Kazuo Nishimura, Ken-Ichi Shimomura, and Stephen J. Turnovsky. We thank the anonymous referee for his/her helpful comments. Iwasa would like to acknowledge financial support from Research Fellowships of the Japan Society for the Promotion of Science for Young Scientists. Professor Koji Shimomura passed away on February 24, 2007. This paper was completed after his untimely death.     

Optimal Categorical Transfer Payments: The Welfare Economics of Limited Lump-Sum Redistribution

Despite their importance in tax-transfer systems, categorical transfer payments, based on (nearly) exogenous characteristics such as disability or date of birth, have been deemphasized in optimal-tax analysis. I use the well-developed theory of first-best redistribution to clarify the welfare economics of categorical transfers, which are a form of limited lump-sum redistribution. The comparison to first-best redistribution explains how categorical transfers affect groups' labor supplies and utility levels, why the use of categorical transfers is inversely related to the planner's inequality aversion, and why their use reduces the optimal income tax rate.     

An income fluctuation problem

A consumer has a t period planning horizon problem, at each period, he gets additionals incomes that are i.i.d. random variables, and he must decide how much of his income will be spent in consumption, yielding some utility, and how much will be saved to maximize the total expected utility. No borrowing is allowed, and for the amounts saved no interest is paid. Using the concepts of competitive prices it is shown that as t → ∞ the corresponding limit of the consumption policy is strictly bounded above by the expected value of the random income.     

Dual interpersonal comparisons of utility and the welfare economics of income distribution

Interpersonal comparisons can be of utility levels and/or of utility differences. Comparisons of levels can be used to define equity in distributing income. Comparisons of differences can be used to construct an additive Bergson social welfare function over income distributions. When both utility levels and utility differences are compared, one can require the constructed additive Bergson social welfare function to indicate a preference for more equitable income distributions. This restricts the form of both the individual utility functions and the optimal distribution of income. The form of these restrictions depends on whether the levels and differences of the same utility functions are being compared.