Minimizing Regret: The General Case

In repeated games with differential information on one side, the labelling "general case" refers to games in which the action of the informed player is not known to the uninformed, who can only observe a signal which is the random outcome of his and his opponent's action. Here we consider the problem of minimizing regret (in the sense first formulated by Hannan [8]) when the information available is of this type. We give a simple condition describing the approachable set.Minimize regret;differential information;approachability

Sophisticated Players and Sophisticated Agents

A sophisticated player is an individual who takes the action of the opponents, in a strategic situation, as determined by decision of rational opponents, and acts accordingly. A sophisticated agent is rational in the choice of his action, but ignores the fact that he is part of a strategic situation. We discuss a notion of equilibrium with sophisticated agents, we provide conditions for its existence, and argue that it differs systematically from the Nash equilibrium.Procedural rationality;sophisticated agents

Life satisfaction, household income and personality traits

We show that personality traits mediate the effect of income on Life Satisfaction. The effect is strong in the case of Neuroticism, which measures the sensitivity to threat and punishment, in both the British Household Panel Survey and the German Socioeconomic Panel. Neuroticism increases the usually observed concavity of the relationship: Individuals with higher Neuroticism score enjoy income more than those with lower score if they are poorer and enjoy income less if they are richer. When the interaction between income and neuroticism is introduced, income does not have significant effect on his own. To interpret the results, we present a simple model where we assume that (i) Life Satisfaction is dependent from the gap between aspired and realized income, and this is modulated by Neuroticism and (ii) income increases in aspirations with a slope less than unity, so that the gap between aspired and realized income increase with aspirations. From the estimation of this model we argue that poorer tend to overshoot in their aspiration, while rich tend to under-shoot. The estimation of the model also shows substantial effect of traits on income

Equilibria with social security

We model pay-as-you-go (PAYG) social sucurity systems as the outcome of majority voting within a standard OLG model with production and an exogenous population growth rateo At each point in time individuals work, save, consume and invest by taking the social security policy as given. The latter consists of a tax on current wages transferred to elderly people. When they vote, individuals have to make two choices: If they want to keep the committment made by the previous generation by paying the elderly the promised amount of benefits, and which amount they want paid to themselves next periodo We show that when the growth rate of population is high enough compared to the productivity of capital there exists an equilibrium where PAYG pensions are voted into existence and maintained. PAYG systems are kept even when everybody knows that they will surely be abondoned, and that some generation will pay and not be paid back. We characterize the steady state and dynamic properties of these equilibria and study their welfare properties. Equilibria achieved by voting are typically inefficient; however, they may be so due to overaccumulation, as well as, in other cases, due to under accumulation. On the other hand, the efficient steady states turn out to be dynamically unstable: so we are presenting an unpleasant alternative for policy making

Work for Image and Work for Pay

Standard economic models with complete information predict a positive, monotonic relationship between pay and performance. This prediction does not always hold in experimental tests: offering a small payment may result in lower performance than not offering any payment. We test experimentally two main explanations that have been put forward for this result: the "incomplete contract" hypothesis views the payment rule as a signal given to subjects on purpose of the activity. The "informed principal" hypothesis views it as a signal concerning the characteristics of the agent or of the task. The incomplete contract view appears to offer the best overall explanation for our results. We also find that high-powered monetary incentives do not "crowd out" intrinsic motivation, but may elicit "too much" effort when intrinsic motivation is very high.

What is perfect competition?

Includes bibliographical references (p. 38-39)

Optimal Taxes Without Commitment.

In the problem of optimal taxation in an economy with two productive factors, labor and capital, the optimal solution when the government can commit to a sequence of tax rates, has the tax on capital tending to zero in the limit, with all the tax burden on labour. It is well known, however, that this solution is time inconsistent; so if the commitment power is not perfect, this second best tax plan will not be suitable. We model explicitly the tradeoff between the cost of revising the tax plan, and the benefit of the revision.FISCAL POLICY;CAPITAL;TAXES;TAXATION

Organizing effects of testosterone and economic behavior: not just risk taking

Recent literature emphasizes the role that testosterone, as well as markers indicating early exposure to T and its organizing effect on the brain (such as the ratio of second to fourth finger,D2:D4), have on performance in financial markets. These results may suggest that the main effect of T, either circulating or in fetal exposure, on economic behavior occurs through the increased willingness to take risks. However, these findings indicate that traders with a low digit ratio are not only more profitable, but more able to survive in the long run, thus the effect might consist of more than just lower risk aversion. In addition, recent literature suggests a positive correlation between abstract reasoning ability and higher willingness to take risks. To test the two hypotheses of testosterone on performance in financial activities (effect on risk attitude versus a complex effect involving risk attitude and reasoning ability), we gather data on the three variables in a sample of 188 ethnically homogeneous college students (Caucasians). We measure a D2:D4 digit ratio, abstract reasoning ability with the Raven Progressive Matrices task, and risk attitude with choice among lotteries. Low digit ratio in men is associated with higher risk taking and higher scores in abstract reasoning ability when a combined measure of risk aversion over different tasks is used. This explains both the higher performance and higher survival rate observed in traders, as well as the observed correlation between abstract reasoning ability and risk taking. We also analyze how much of the total effect of digit ratio on risk attitude is direct, and how much is mediated. Mediation analysis shows that a substantial part of the effect of T on attitude to risk is mediated by abstract reasoning ability

Sequential Common Agency

In a common agency game a set of principals promises monetary transfers to an agent which depend on the action he will take. The agent then chooses the action, and is paid the corresponding transfers. Principals announce their transfers simultaneously. This game has many equilibria; Bernheim and Whinston ([1]) prove that the action chosen in the coalition-proof equilibrium is e±cient. The coalition-proof equilibria have an alternative characterization as truthful equilibria. The other equilibria may be inefficient. Here we study the sequential formulation of the common agency game: principals announce their transfers sequentially. We prove that the set of equilibria is different in many important ways. The outcome is efficient in all the equilibria. The truthful equilibria still exist, but are no longer coalition-proof. Focal equilibria are now a different type of equilibria, that we call thrifty. In thrifty equilibria of the sequential games, principals are better off (and the agent worse off) than in the truthful equilibria of the simultaneous common agency. These results suggest that the sequential game is more desirable institution, because it does not have ine±cient equilibrium outcomes; but it is less likely to emerge when agents have the power to design the institution.Common agency;sequential games;principal agent games;political influence