An auction mechanism for public goods provision: an experimental study

We experiment a new mechanism for the provision of a discrete public good: in a fixed period individuals can contribute several times; at any moment they can see the total amount collected; at the end of the period, the public good is provided if the amount covers the cost. We find that the ability of the mechanism to provide efficiently the public good decreases with the amount of the provision cost.Public Goods, Experiments, Mechanism Design

The Individual Behavior in a Public Goods game

Generally, with a standard linear public goods game, one observes at the aggregate level that contributions lay between the Nash equilibrium and the social optimum and decrease over time with an end-effect.Our purpose is to see whether these general aggregate results remain available at the group and at the individual levels. To do so, we formed six groups of four persons and made them play a public goods game. At the aggregate level, we find that our results correspond almost to the standard experimental findings in literature.Using the classification of Isaac et al. (1984), we find that at the group level, only two groups adopt the standard behavior and only two groups present a behavior similar to what we obtain at the aggregate level. At the individual level, we compare contributions over time of each subject to the group and the aggregate results and classify them into types. Only in one of the 6 groups individuals adopt an homogeneous behavior. In the five other groups, individuals have different behaviors.Public Goods; Free-Riding; Aggregate level; Individual Behavior; Experiments.

Interior Collective Optimum in a Volontary Contribution to a Public-Goods Game : An Experimental Approach

We run a public good experiment with four different treatments. The payoff function is chosen such that the Nash equilibrium (NE) and the collective optimum (CO) are both in the interior of the strategy space. We try to test the effect of varying the level of the collective optimum, which changes the "social dilemma", involved in the decision as to how much to contribute to the public good . Our results show that contributions increase with the level of the interior CO. There is overcontribution in comparison to the NE and under contribution in comparison to the CO. But contributions are as far from the CO as the level of this former gets high. An overcontribution index that takes into account the effective contribution relative to both, the NE and the CO, shows that subjects adopt a constant behavior while passing from one treatment to another: they contribute a constant share of the CO.Public Goods, Experiments, Interior Solutions, Social Dilemma

Interior collective optimum in a volontary contribution to a public-goods game : an experimental approach

We run a public goods experiment with four different treatments. The payoff function is chosen such that the Nash equilibrium (NE) and the collective optimum (CO) are both in the interior of the strategy space. We test the effect of varying the level of the collective optimum on contributions. The results show that contributions increase with the level of the CO.Public goods, Experiments, interior solutions, social dilemma

The Emergence of Coordination in Public Good Games

In physical models it is well understood that the aggregate behaviour of a system is not in one to one correspondence with the behaviour of the average individual element of that system. Yet, in many economic models the behaviour of aggregates is thought of as corresponding to that of an individual. A typical example is that of public goods experiments. A systematic feature of such experiments is that, with repetition, people contribute less to public goods. A typical explanation is that people “learn to play Nash” or something approaching it. To justify such anexplanation, an individual learning model is tested on average or aggregate data. In this paper we will examine this idea by analysing average and individual behaviour in a series of public goods experiments. We analyse data from a series of games of contributions to public goods and firstly to see what happens, if we follow the standard approach and test a learning model on the average data. We then look at individual data, examine the changes that this produces and see if somegeneral model such as the EWA (Expected Weighted Attraction) with varying parameters can account for individual behaviour. We find that once we disaggregate data such models have poor explanatory power. Groups do not learn as supposed, their behaviour differs markedly from one group to another, and the behaviour of the individuals who make up the groups also varies within groups. The decline in aggregate contributions cannot be explained by resorting to a uniformmodel of individual behaviour.Experimental Economics; Public Goods; Learning models;Individual and Aggregate behaviour.

Dynamic voluntary contributions to a discrete public good:Experimental evidence

We experiment a mechanism for the provision of a discrete public good where individuals are allowed to update upwards their contribution during a fixed time interval. Experimental evidence shows that subjects increase their contributions in order to finance the cost of the good. The public good is financed more frequently when its cost is low relative to the social ability to pay.Public Goods; Experiments; Voluntary contributions; Dynamic contributions

Threshold of Preference for Collusion and Interconnection Fees in Different Market Structures : the Tunisian Mobile Market Case

We present a Cournot model that compares the critical threshold of collusion in Duopoly and Oligopoly Markets where the actors are private, mixed or public. We assume that the incentive critical threshold for collusion depends on the interconnection fees. The different threshold values calculated in each Market structure are then estimated, using the OLS method, with variables related to the Tunisian market structures and prices. The Econometric estimation of the different threshold values is consistent with our theoretical results. Our findings can be used by the decision makers to control collusion, by acting on the level of interconnection fees for each market structure and by implementing the suitable market liberalization policies in this sector

Dynamic voluntary contributions to a discrete public good:<br />Experimental evidence

International audienceWe experiment a mechanism for the provision of a discrete public good where individuals are allowed to update upwards their contribution during a fixed time interval. Experimental evidence shows that subjects increase their contributions in order to finance the cost of the good. The public good is financed more frequently when its cost is low relative to the social ability to pay

An auction mechanism for public goods provision: an experimental study

We experiment a new mechanism for the provision of a discrete public good: in a fixed period individuals can contribute several times; at any moment they can see the total amount collected; at the end of the period, the public good is provided if the amount covers the cost. We find that the ability of the mechanism to provide efficiently the public good decreases with the amount of the provision cost

Interior Collective Optimum in a Volontary Contribution to a Public-Goods Game : An Experimental Approach

We run a public good experiment with four different treatments. The payoff function is chosen such that the Nash equilibrium (NE) and the collective optimum (CO) are both in the interior of the strategy space. We try to test the effect of varying the level of the collective optimum, which changes the "social dilemma", involved in the decision as to how much to contribute to the public good . Our results show that contributions increase with the level of the interior CO. There is overcontribution in comparison to the NE and under contribution in comparison to the CO. But contributions are as far from the CO as the level of this former gets high. An overcontribution index that takes into account the effective contribution relative to both, the NE and the CO, shows that subjects adopt a constant behavior while passing from one treatment to another: they contribute a constant share of the CO