我国城市居民最低生活保障标准的影响因素与效应研究

近年来,我国各地城市居民最低生活保障标准不断提升.本文利用我国36个城市1998-2005年的面板数据,分析影响城市居民最低生活保障标准动态变迁的经济、政治和社会因素及其影响效应,结果显示:城市居民最低生活保障制度是最低生活保障而非基本生活保障;"低保"标准并未有效地缩小贫富差距;"低保"标准对贫困者就业意愿具有较弱的负效应.针对上述问题,笔者提出建议:对应经济社会的发展动态提高标准、施行分层梯度式"低保"标准以及建立互动支持系统,促进"低保"受益者就业.     

Inductive reasoning about unawareness

We develop a model of games with awareness that allows for differential levels of awareness. We show that, for the standard modal-logical interpretations of belief and awareness, a player cannot believe there exist propositions of which he is unaware. Nevertheless, we argue that a boundedly rational individual may regard the possibility that there exist propositions of which she is unaware as being supported by inductive reasoning, based on past experience and consideration of the limited awareness of others. In this paper, we provide a formal representation of inductive reasoning in the context of a dynamic game with differential awareness. We show that, given differential awareness over time and between players, individuals can derive inductive support for propositions expressing their own unawareness. We consider the ecological rationality of heuristics to guide decisions in problems involving differential awareness.     

Social memory,evidence, and conflict

This paper examines an equilibrium model of social memory — a society's vicarious beliefs about its past. We show that incorrect social memory is a key ingredient in creating and perpetuating destructive conflicts.We analyze an infinite-horizon model in which two countries face off each period in a game of conflict characterized by the possibility of mutually destructive “all out war” that yields catastrophic consequences for both sides. Each country is inhabited by a dynastic sequence of individuals. Each individual cares about future individuals in the same country, and can communicate with the next generation of their countrymen using private messages. Social memory is based on these messages, and on physical evidence — a sequence of imperfectly informative public signals of past behavior. We find that if the future is sufficiently important for all individuals, then regardless of the precision of physical evidence from the past there is an equilibrium in which the two countries engage in all out war with arbitrarily high frequency, an outcome that cannot arise in the standard repeated game. In our construction, each new generation “repeats the mistakes” of its predecessors, leading to an endless cycle of destructive behavior.Surprisingly, we find that degrading the quality of information that individuals have about current decisions may “improve” social memory. This in turn ensures that arbitrarily frequent all out wars cannot occur.     

Self‐Assessed Social Position and Poverty

In this article, we use microlevel data extracted from the 2006 Japanese General Social Surveys to analyze the relationships between self‐assessed social position and socioeconomic factors such as income and poverty. We provide the posterior results of the estimation of the Bayesian multivariate ordered probit model and propose an inequality measure for self‐assessed social position on the basis of the posterior results. We call the inequality measure “regret” and show that the distributions of regret differ for people above and below the poverty line.     

Poverty and social exclusion: two sides of the same coin or dynamically interrelated processes?

There is growing interest in the analysis and measurement of social exclusion, to complement the static and dynamic literature on income poverty. On theoretical grounds, social exclusion and income poverty are seen as different processes, but with closely interrelated dynamics. However, our empirical understanding of the way these two processes dynamically interact at the individual level is still very limited. To shed some light on the issue, we use a dynamic bivariate probit model, controlling for unobserved heterogeneity and Wooldridge (2005)-type initial conditions. Both the first- and second-order Markov dynamics are examined. We estimate the model using the Italian sample of the European Community Household Panel (ECHP), waves 1–8, and find a sizable extent of state dependence in both poverty and social exclusion. Moreover, there are dynamic cross-effects implying that poverty and social exclusion are mutually reinforcing. Social policies aimed at eradicating poverty and avoiding individuals’ social and economic marginalization should take these interaction effects explicitly into account.     

Capabilities and Functionings: The Role of Social Capital for Accessing New Capabilities

This paper connects two relatively recent streams of research in social science: the capabilities approach and the literature on social capital. The aim is to show that these are strictly connected in a dynamic process linking functionings and capabilities through social capital. The ability to attain new capabilities is enhanced by the possession of social capital; hence investing in its accumulation allows individuals to improve their welfare. Furthermore, new capabilities allow the individual to create new connections and access new networks, accruing his or her stock of social capital and opening the door to the possibility of attaining new capabilities. The paper hypothesizes that a dynamic spiral interweaves social capital, capabilities and functionings.     

Pay-as-you-go Social Security and the Distribution of Altruistic Transfers

This paper studies the impact of an unfunded social security system on the distribution of altruistic transfers in a framework where savings are due to both life cycle and random altruistic motivations. We show that the effect of social security on the distribution of these transfers depends crucially on the strength of the bequest motive in explaining savings behaviour. We measure this strength by the expected weight that individuals attach to the utility of future generations. On the one hand, if the bequest motive is strong, then an increase in the social security tax raises the bequests left by altruistic parents. On the other hand, when the importance of altruism in motivating savings is sufficiently low, the increase in the social security tax could result in a reduction of the bequests left by altruistic parents under some conditions on the attitude of individuals toward risk and on the relative returns associated with private saving and social security. Some implications concerning the transitional effects of introducing an unfunded social security scheme are also discussed.     

Correlated Equilibrium,Conformity, and Stereotyping in Social Groups

We argue that a social norm and the coordination of behavior within social groups can be expressed by a correlated equilibrium. Given a social group structure (a partition of individuals into social groups), we propose four conditions that one may expect of a correlated equilibrium consistent with social norms. These are: (1) within‐group anonymity (conformity within groups), (2) group independence (no conformity between groups), (3) homophily (individuals in the same group have similar attributes), and (4) predictable group behavior (ex post stability). We demonstrate that correlated equilibrium satisfying (1)–(3) exist very generally and equilibrium satisfying (1)–(4) exist in games with many players. We also consider stereotyped beliefs—beliefs that all individuals in a social group can be expected to behave in the same way—and show that stereotyping is not costly to the person who stereotypes but may or may not be beneficial to society.     

The impact of two different economic systems on dishonesty

Using an artefactual field experiment, this paper tests the long-term implications of living in a specific economic system on individual dishonesty. By comparing cheating behaviour across individuals from the former socialist East of Germany with those of the capitalist West of Germany, we examine behavioural differences within a single country. We find long-term implications of living in a specific economic system for individual dishonesty when social interactions are possible: participants with an East German background cheated significantly more on an abstract die-rolling task than those with a West German background, but only when exposed to the enduring system of former West Germany. Moreover, our results indicate that the longer individuals had experienced socialist East Germany, the more likely they were to cheat on the behavioural task.     

Heterogeneity,impatience, and dynamic private provision of a discrete public good

We analyze dynamic private provision of a discrete public good by heterogeneous agents, who differ in terms of their levels of impatience, in a differential game framework. In contrast to the strategic complementarity result for homogeneous individuals, we show that an asymmetric completion Markov perfect equilibrium exists, where the individual contributions and the strategic behaviors depend crucially on an impatience differential: the difference in rates of time preference across groups of individuals. When this differential is insignificant, contributions of both types of individuals are strategic complements. On the other hand, when this impatience differential exceeds a threshold, the contributions of impatient individuals become strategic substitutes, whereas the contributions of patient individuals remain strategic complements. We show that group size has an interesting role to play in the strategic behavior: increasing the number of patient individuals aggravates the incentives to free‐ride by the impatient agents. We also derive a condition under which all the socially beneficial projects get completed in the equilibrium.     

Social responsibility promotes conservative risk behavior

Previous studies show that group risk taking can be more conservative than individual risk taking. Two common, but untested reasons for this greater caution are the influence of social responsibility and a tendency to conform to the preferences of others. We study changes in risk taking in simple settings, where another’s risk taking can sometimes be observed, and where decisions affect not only one’s own payoffs but sometimes also affect those of a passive, second party. We find that social responsibility leads to more conservative risk behavior in group decision making. Conformism has a more symmetric effect: observing the choice of another tends to lead both individual and social decisions toward whatever the other’s expressed risk preference is. Direct tests fail to link the social behavior we observe to the social preference for distributional fairness common in decision-making under certainty.     

Income-contingent loan with personal insurance policy: an empirical assessment using Spanish data

We propose an Income Contingent Loan that defers the payment of university fees and charges a fixed proportion of gross income for 30 years or until the debt is written off. Under these conditions, some participants in the scheme will have insufficient income to fully repay their loan balances. The deficit will be covered by the taxpayer, who ultimately bears the risk of investing in higher education. We then propose to transfer this risk to the student by adding a mandatory personal insurance policy to the individual loan. We calculate the premium required for the system to break even in Spain when everybody pays the insurance cost. Alternatively, the payment of the premium can be deferred, adding it to total debt. Then, some participants in the scheme will have insufficient income to even pay the insurance cost, and the premium needs to be increased to maintain the sustainability of the program. Although these mechanisms imply redistribution towards borrowers who end up being low earners, we show that middle-income individuals contribute a higher proportion of their incomes to covering for those unable to repay. To provide the system with more internal progressivity, we propose to impose a minimum period of repayment.     

Regular Distributive Efficiency and the Distributive Liberal Social Contract

We consider abstract social systems of private property, made of n individuals endowed with nonpaternalistic interdependent preferences, who interact through exchanges on competitive markets and Pareto‐improving lump‐sum transfers. The transfers follow from a distributive liberal social contract defined as a redistribution of initial endowments such that the resulting market equilibrium allocation is both: (i) a distributive optimum (i.e., is Pareto‐efficient relative to individual interdependent preferences) and (ii) unanimously weakly preferred to the initial market equilibrium. We elicit minimal conditions for meaningful social contract redistribution in this setup, namely, the weighted sums of individual interdependent utility functions, built from arbitrary positive weights, have suitable properties of nonsatiation and inequality aversion; individuals have diverging views on redistribution, in some suitable sense, at (inclusive) distributive optima; and the initial market equilibrium is not a distributive optimum. We show that the relative interior of the set of social contract allocations is then a simply connected smooth manifold of dimension n ? 1. We also show that the distributive liberal social contract rules out transfer paradoxes in Arrow–Debreu social systems. We show, finally, that the liberal social contract yields a norm of collective action for the optimal provision of any pure public good.     

PRIVATE PROVISION OF PUBLIC GOODS AND INFORMATION DIFFUSION IN SOCIAL GROUPS

I describe a dynamic model of costly information sharing where private information affecting collective‐value actions is transmitted by social proximity. Individuals make voluntary contributions toward the provision of a pure public good, and information transmission about quality of provision is a necessary condition for collective provision to take place in a stationary equilibrium. I show that unlike in the case of private goods, better informed individuals face positive incentives to incur a cost to share information with their neighbors and that these incentives are stronger and provision of the pure public good greater the smaller are individuals' social neighborhoods.     

Vaccination under pessimistic expectations in clinical trials and immunization campaigns

We provide one of the first formalizations of a vaccination campaign in a decision-theoretic framework. We analyze a model where an ambiguity-averse individual must decide how much effort to invest into prevention in the context of a rampant disease. We study how ambiguity aversion affects the effort and the estimation of the vaccine efficacy in clinical trials and immunization campaigns. We find that the behaviors of individuals participating in a clinical trial differ from individuals not participating. Individuals who are more optimistic toward vaccination participate more in trials. Their behaviors and efforts are also affected. As a result, because vaccine efficacy depends on unobserved behaviors and efforts, the biological effect of the vaccine becomes difficult to evaluate. During the scale-up phase of a vaccination campaign, provided that vaccine efficacy is established, we show that vaccine hesitancy may still be rational.     

The Evolution of Social and Economic Networks

We examine the dynamic formation and stochastic evolution of networks connecting individuals. The payoff to an individual from an economic or social activity depends on the network of connections among individuals. Over time individuals form and sever links connecting themselves to other individuals based on the improvement that the resulting network offers them relative to the current network. In addition to intended changes in the network there is a small probability of unintended changes or errors. Predictions can be made regarding the likelihood that the stochastic process will lead to any given network at some time, where the stochastic process selects from among the statically stable networks and cycles. We apply these results to examples including the Gale-Shapley marriage problem. Thus the paper achieves two goals. First, it outlines a dynamic solution concept for networks. Second, it applies this concept to matching problems. Journal of Economic Literature Classification Numbers: A14, D20, J00.     

Hayekian expectations: Theory and empirical applications

We show that the orderliness of market processes and outcomes, and hence the realization and coordination of individuals' plans, are dependent on the social environment in which individuals function. In specific, when atomicity and stable (social) rules are compromised in the case of Big Players, markets are less orderly despite the fact that individuals are behaving rationally.—The paper provides an account of individual rationality by generating a theory of expectations based on Hayek's cognitive theory. Hayekian expectations are coherent, competitive, and endogenous. This suggests that expectational analysis must take account of the context of constraint—the “environment” or what we call “filtering conditions”—within which individuals function and to which they must adapt. The paper provides a theoretical analysis of expectations at the individual level and shows that the particular behaviors stemming from those expectations require a specification of the rules governing social and market activities. We thank Karen Palasek, Don Boudreaux, Joe Cobb, Peter Boettke, and the participants of the Hayek 1993 Memorial Symposium in Freiburg, Germany for helpful suggestions and comments on earlier drafts. All remaining errors are ours.     

Pecunia non olet: on the self-selection into (dis)honest earning opportunities

Experimental Economics - We study self-selection into earning money in an honest or dishonest fashion based on individuals’ attitudes toward truthful reporting. We propose a...     

Higher-order risk preferences in social settings

We study prudence and temperance (next to risk aversion) in social settings. Previous experimental studies have shown that these higher-order risk preferences affect the choices of individuals deciding privately on lotteries that only affect their own payoff. Yet, many risky and financially relevant decisions are made in the social settings of households or organizations. We elicit higher-order risk preferences of individuals and systematically vary how an individual’s decision is made (alone or while communicating with a partner) and who is affected by the decision (only the individual or the partner as well). In doing so, we can isolate the effects of other-regarding concerns and communication on choices. Our results reveal that the majority of choices are risk averse, prudent, and temperate across social settings. We also observe that individuals are influenced significantly by the preferences of a partner when they are able to communicate and choices are payoff-relevant for both of them.     

Dynamic management of water transfer between two interconnected river basins

This paper analyzes the dynamic interaction between two regions with interconnected river basins. Precipitation is higher in one river-basin while water productivity is higher in the other. Water transfer increases productivity in the recipient basin, but may cause environmental damage in the donor basin. The recipient faces a trade-off between paying the price of the water transfer, or investing in alternative water supplies to achieve a higher usable water capacity. We analyze the design of this transfer using a dynamic modeling approach, which relies on non-cooperative game theory, and compare solutions with different information structures (Nash open-loop, Nash feedback, and Stackelberg) with the social optimum. We first assume that the equilibrium between supply and demand determines the optimal transfer price and amount. We show that, contrary to the static case, in a realistic dynamic setting in which the recipient uses a feedback information structure the social optimum will not emerge as the equilibrium solution. We then study different leadership situations in the water market and observe that the transfer amount decreases toward a long-run value lower than the transfer under perfect competition, which in turn lays below the social optimum. In consequence, the water in the donor's river-basin river converges to a better quality in the presence of market power. Finally, we numerically compare our results to the Tagus-Segura water transfer described in Ballestero (2004). Welfare gains are compared for the different scenarios. We show that in all dynamic settings, the long-run transfer amount is lower than in Ballestero's static model. Further, we show that the long-run price settles at a lower level than in Ballestero's model, but is still higher than the average cost-based price determined by the Spanish government.