Measuring player’s behaviour change over time in public goods game

An important issue in public goods game is whether player's behaviour changes over time, and if so, how significant it is. In this game players can be classified into different groups according to the level of their participation in the public good. This problem can be considered as a concept drift problem by asking the amount of change that happens to the clusters of players over a sequence of game rounds. In this study we present a method for measuring changes in clusters with the same items over discrete time points using external clustering validation indices and area under the curve. External clustering indices were originally used to measure the difference between suggested clusters in terms of clustering algorithms and ground truth labels for items provided by experts. Instead of different cluster label comparison, we use these indices to compare between clusters of any two consecutive time points or between the first time point and the remaining time points to measure the difference between clusters through time points. In theory, any external clustering indices can be used to measure changes for any traditional (non-temporal) clustering algorithm, due to the fact that any time point alone is not carrying any temporal information. For the public goods game, our results indicate that the players are changing over time but the change is smooth and relatively constant between any two time points

Asymmetric Obligations

We use a laboratory experiment to investigate the behavioral effects of obligations that are not backed by binding deterrent incentives. To implement such ‘expressive law’ we introduce different levels of very weakly incentivized, symmetric and asymmetric minimum contribution levels (obligations) in a repeated public goods experiment. The results provide evidence for a weak expressive function of law: while the initial impact of high obligations on behavior is strong, it decreases over time. Asymmetric obligations are as effective as symmetric ones. Our results are compatible with the argument that expressive law affects behavior by attaching an emotional cost of disobeying the own obligation.non-binding obligations, expressive law, public goods, experiment

Asymmetric obligations

We use a laboratory experiment to investigate the behavioral effects of obligations that are not backed by binding deterrent incentives. To implement such expressive law' we introduce different levels of very weakly incentivized, symmetric and asymmetric minimum contribution levels (obligations) in a repeated public goods experiment. The results provide evidence for a weak expressive function of law: while the initial impact of high obligations on behavior is strong, it decreases over time. Asymmetric obligations are as effective as symmetric ones. Our results are compatible with the argument that expressive law affects behavior by attaching an emotional cost of disobeying the own obligation. --Non-binding Obligations,Expressive law,Public goods,Experiment

The Economics of Fairness, Reciprocity and Altruism – Experimental Evidence and New Theories

This paper surveys recent experimental and field evidence on the impact of concerns for fairness, reciprocity and altruism on economic decision making. It also reviews some new theoretical attempts to model the observed behavior.Behavioural Economics; Other-regarding Preferences; Fairness; Reciprocity; Altruism; Experiments; Incentives; Contracts; Competition

The Economics of Fairness, Reciprocity and Altruism – Experimental Evidence and New Theories

Chapter written for the Handbook of Reciprocity, Gift-Giving and AltruismBehavioural Economics; Other-regarding Preferences; Fairness; Reciprocity; Altruism; Experiments; Incentives; Contracts; Competition

An Experimental Contribution to the Theory of Customary (International) Law

In their majority, public international lawyers postulate that for a new rule of customary law to originate, two conditions must be fulfilled: there must be consistent practice, and it must be shown that this practice is motivated by the belief that such behaviour is required in law. Maurice Mendelson (Recueil des Cours 272 (1998) 155) has challenged this view. He believes that the majority view ignores the fundamentally incomplete nature of public international law. He claims that the new rule emerges because mere practice leads to convergent expectations. This paper uses data from student experiments with a linear public good to show that behaviour con-verges even absent verbal communication; that convergence is guided by mean contributions in the previous round, which serve as an implicit norm; that freeriding on this implicit norm is re-garded as illegitimate; that cooperation can be stabilised at a high level if “reprisals” are permitted. Hence the mechanism of norm formation proposed by Maurice Mendelson is fully borne out by the experimental data.experiment, customary international law, opinio iuris, linear public good

Building trust? Conditional cash transfers and social capital

In this paper we propose a measure of social capital based on the behaviour in a public good game. We play the public good game within 28 groups in two similar neighborhoods in Cartagena, Colombia, one of which had been targeted for over two years by a conditional cash transfer program that has an important social component. The level of cooperation we observe in the ‘treatment’ community is considerably higher than in the ‘control’ community. The two neighborhoods, however, although similar in many dimensions, turned out to be significantly different in other observable variables. The result we obtain in terms of cooperation, however, is robust to controls for these observable differences. In the last part of the paper we also compare our measure of social capital with other more traditional measures that have been used in the literature

The Inter-Institutional Distribution of Power in EU Codecision

This paper analyzes the a priori influence of the European Parliament (EP) and the Council of Ministers (CM) on legislation of the European Union adopted under its codecision procedure. In contrast to studies which use conventional power indices, both institutions are assumed to act strategically. Predicted bargaining outcomes of the crucial Conciliation stage of codecision are shown to be strongly biased towards the legislative status quo. Making symmetric preference assumptions for members of CM and EP, CM is on average much more conservative because of its internal qualified majority rule. This makes CM by an order of magnitude more influential than EP, in contrast to a seeming formal parity between the two ‘co-legislators’.power measurement, European Union codecision procedure, bargaining, spatial voting, decision procedures