A contrasting look at self-organization in the Internet and next-generation communication networks

This article examines contrasting notions of self-organization in the Internet and next-generation communication networks, by reviewing in some detail recent evidence regarding several of the more popular attempts to explain prominent features of Internet structure and behavior as "emergent phenomena." In these examples, what might appear to the nonexpert as "emergent self-organization" in the Internet actually results from well conceived (albeit perhaps ad hoc) design, with explanations that are mathematically rigorous, in agreement with engineering reality, and fully consistent with network measurements. These examples serve as concrete starting points from which networking researchers can assess whether or not explanations involving self-organization are relevant or appropriate in the context of next-generation communication networks, while also highlighting the main differences between approaches to self-organization that are rooted in engineering design vs. those inspired by statistical physics

Framing and cooperation in public good games: an experiment with an interior solution.

We show that experimental subjects tend to contribute more to the public good if they perceive the actions of the others as a source of positive externality rather than a source of negative externality. In our experiment partial contribution to the public good is the unique subgame perfect equilibrium for the repeated game.experimental economics, public goods

Are Athletes Different ? An Experimental Study Based on the Ultimatum Game

Sport, Athletes, Economic behavior, Experiments, Ultimatum game.

The role of players’ identification in the population on the trusting and the trustworthy behavior an experimental investigation

We study to what extent identification does matter for trustfulness and trustworthiness to emerge in a population of players. Our experimen- tal protocol is designed for isolating the effects of trustees’ identification. Trustees’ identification is a necessary condition for introducing a reputation mechanism. We run three treatments. In each treatment groups 6 players interact repeatedly and randomly and play a 30 periods investment game (Berg & al. 1995). In the first treatment players can’t identify each other, in the second one players can identify each other as trustee and in the third one players identify each other both as trustee and trustor. We show that, according to the expectation, trustees’ identification has a positive effect on reciprocity. However it doesn’t affect the average trust in the population. Trust is significantly higher than in the complete anonymous treatment only when players identify each other in both roles. We show that this enhance of trust is the result of mutual trust-reciprocity relationships formation.

Does Contributing Sequentially Increase the Level of Cooperation in Public Goods Games ? An Experimental Investigation

We run a series of experiments in which subjects have to choose their level of contribution to a pure public good. Our design differs from the standard public good game with respect to the decision procedure. Instead of deciding simultaneously in each round, subjects are randomly ordered in a sequence which differs from round to round. We compare sessions in which subjects can observe the exact contributions from earlier decisions ("Sequential treatment with Information") to sessions in which subjects decide sequentially but cannot observe earlier contributions ("Sequential treatment without information"). Furthermore, we investigate the effect of group size on aggregate contributions. Our result indicate that contributing sequentially increases the level of contribution to the public good when subjects are informed about the contribution levels of lower ranked subjects. Moreover, we observe that earlier players in the sequence try to influence positively the contributions of subsequent decision makers in the sequence, by making a large contribution. Such behaviour is motivated by the belief that subsequent players will reciprocate by also making a large contribution.

Misreporting, retroactive audit and redistribution.

In this paper, we investigate an audit policy that allows a regulator to control past declarations of an agent who is caught to fraud in the current period or to adopt an action that is not desirable for Society. Coupled with redistribution effects due to the production of a public good, we show that retroactivity has not always the desired effect on the level of evasion or the level of effort, once the agent has decided to deviate from a given objective. Nevertheless, we derive conditions under which retroactivity lessens fraudulent behaviors, in quantity and in value. As a related result, authorities should communicate about how they use the individual contributions but information should not be completely transparent in order to fight efficiently against deviation. Redistribution and retroactivity may have opposite effects on the behavior of the agent when combined together.moral hazard, retroactive audit, redistribution, public good, fraud.

Fixed Instruments to Cope with Stock Externalities An Experimental Evaluation

We evaluate the effectiveness of non optimal and temporally inconsistent incentive policies for regulating the exploitation of a renewable common-pool resource. The corresponding game is an N-person discrete-time deterministic dynamic game of T periods fixed duration. Three policy instruments with parameters that remain constant for the whole horizon are evaluated: a pigouvian tax (flat tax), an ambient tax (ambient flat tax) and an instrument combining the two previous ones (mixed flat instrument). We test in the lab the predictions of the model solved for 3 distinct behavioural assumptions: (a) sub-game perfection, (b) myopic behaviour, and (c) joint payoff maximization. We find that subjects behave myopically in the unregulated situation, which agrees with previous results in the literature. Conditional on predictions, the mixed flat instrument and the flat tax are the most effective policies in approaching the optimum extraction path. However, in absolute terms the ambient flat tax and the mixed flat instrument curb most significantly the mean extraction path towards the optimum path. Paradoxically, these instruments are the less efficient ones.Policy Instruments, Renewable Common-pool Resources, Dynamic Externalities, Experimental Economics

THEORIES OF BEHAVIOR IN PRINCIPAL-AGENT RELATIONSHIPS WITH HIDDEN ACTION.

In Keser and Willinger (IJIO, 2000) we found that many contracts offered by experimental subjects do not satisfy incentive compatibility. While the combination of incentive compatibility and a binding participation constraint would require that the agent incurs a net loss in the less favorable state for the principal, experimental subjects in the role of principals propose contracts in which the agent never risks to make a loss. We identified in the principals’ decision making three basic principles that, combined together, describe a fair offers area into which a large number of the observed contract offers falls. These principles imply that net expected surplus is more evenly allocated between the principal and the agent than agency theory predicts. The aim of the experiments presented in this paper is to test the robustness of these principles when the effort costs increase and the net expected surplus becomes smaller, and to compare their predictive success to the predictive success of agency theory under the assumption either of a risk-averse or a risk-neutral agent. The results show that the fair offers prediction describes the observed contract offers better than agency theory as long as an important net expected surplus is created. However, when the effort costs are so high that the net expected surplus is negligible, standard agency theory does better than the combination of the three principles in predicting the observed contract offers.

Managerial incentives under competitive pressure: Experimental investigation

We investigate the effects of competition on managerial incentives and effort in a laboratory experiment. Each owner offers compensation to his manager in two different contexts: monopoly and Cournot duopoly. After accepting the compensation, the manager chooses an effort level to increase the probability of reduced costs of his firm. Theory predicts that the entry of a rival firm in a monopolistic industry affects negatively both the incentive compensation and the effort level. Our experimental findings confirm that the entry of a rival firm reduces the incentive compensation but not the manager’s effort level. However, despite the reduction of the incentive compensation, the manager continues to accept the contract offers and exert the same level of effort.Managerial Incentives, Effort, Competition, Moral hazard, Experiments

Misreporting, Retroactive Audit and Redistribution

In this paper, we investigate an audit policy that allows a regulator to control past declarations of an agent who is caught to fraud in the current period or to adopt an action that is not desirable for Society. Coupled with redistribution effects due to the production of a public good, we show that retroactivity has not always the desired effect on the level of evasion or the level of effort, once the agent has decided to deviate from a given objective. Nevertheless, we derive conditions under which retroactivity lessens fraudulent behaviors, in quantity and in value. As a related result, authorities should communicate about how they use the individual contributions but information should not be completely transparent in order to fight efficiently against deviation. Redistribution and retroactivity may have opposite effects on the behavior of the agent when combined together.