Early or Late Conflict Settlement in a Variety of Games - An Experimental Study -

The game theoretic prediction for alternating offer bargaining depends crucially on how "the pie'' changes over time, and whether the proposer in an early round has ultimatum power. We experimentally study eight such games. Each game is once repeated before being followed by the next one, which defines a cycle of altogether 16 successive plays. Participants play three such cycles. There are no major experience effects but strong and reliable effects of anticipated rule changes. The latter, however, are not due to strategic considerations but rather to the social norms of fairness and efficiency. La théorie des jeux prédit que la résolution des jeux de négociation séquentielle dépend essentiellement de l'évolution de la rente à partager dans le temps (taux d'escompte), et du pouvoir d'ultimatum de l'offreur à la première période. Nous étudions à l'aide de la méthode expérimentale huit jeux de négociation séquentielle afin d'évaluer l'impact du pouvoir de négociation et du taux d'escompte sur les comportements. Chaque jeu est répété une fois avant de passer à un nouveau jeu, notre test est composé de cycle composé de 16 jeux consécutifs. Les participants ont été confrontés à 3 cycles. Au cours du test, aucun effet d'expérience lié à la répétition des jeux n'a été détecté. Les participants ont adopté un comportement stable et robuste d'anticipation des changements de règle de jeu. Les stratégies mises en ?uvre font référence à des considérations, non stratégiques, basées à la fois sur des normes sociales d'équité et d'efficience.Alternating bargaining games, ultimatum, Jeux de négociation séquentiels, ultimatum

Design and Evaluation of an Economic Experiment via the Internet

The paper investigates whether Internet experiments are an appropriate alternative to traditional laboratory experiments. For an economic experiment of individual decision making results obtained over the Internet are compared to results obtained in the laboratory using exactly the same software. Of particular interest are differences in individual behavior. Our main findings are: 1) Running our own experiment on the Internet and in the laboratory generated similar data when economic decision behavior is concerned. (2) Variance in economic decision behavior is generally higher on the Internet experiment. (3) Decision times are shorter on the Internet. (4) Internet software provides a helpful platform for implementing economic experiments. The paper also reports on design challenges and how we have solved them.economics of technology ;

The Active Mirror Control of the MAGIC Telescope

One of the main design goals of the MAGIC telescopes is the very fast repositioning in case of Gamma Ray Burst (GRB) alarms, implying a low weight of the telescope dish. This is accomplished by using a space frame made of carbon fiber epoxy tubes, resulting in a strong but not very rigid support structure. Therefore it is necessary to readjust the individual mirror tiles to correct for deformations of the dish under varying gravitational load while tracking an object. We present the concept of the Active Mirror Control (AMC) as implemented in the MAGIC telescopes and the actual performance reached. Additionally we show that also telescopes using a stiff structure can benefit from using an AMC.Comment: Contribution to the 30th ICRC, Merida, Mexico, July 2007 on behalf of the MAGIC Collaboratio

Discovery of GeV gamma-ray emission from PSR B1259-63/LS 2883

The binary system PSR B1259-63/LS 2883 consists of a 47.8 ms radio pulsar that orbits the companion Be star with a period of 3.4 years in a highly eccentric orbit. The system is well sampled in radio, X-rays, and TeV gamma-rays, and shows orbital-phase-dependent variability in all observed frequencies. Here we report on the discovery of >100 MeV gamma-rays from PSR B1259-63/LS 2883 through the 2010 pariastron passage. Using data collected with the Large Area Telescope aboard Fermi from 33 days before pariastron to 75 days after pariastron, PSR B1259-63/LS 2883 is detected at a significance of 13.6 standard deviations. The gamma-ray light curve is highly variable over the above period, with changing photon index that correlates with gamma-ray flux. In particular, two major flares that occur after the pariastron passage were observed. The onset of gamma-ray emission occurs close to, but not at the same orbital phases as, the two disk passages that occur ~1 month before and ~1 month after the pariastron passage. The fact that the GeV orbital light curve is different from that of the X-ray and TeV light curves strongly suggests that GeV gamma-ray emission originates from a different component. We speculate that the observed GeV flares may be resulting from Doppler boosting effects.Comment: ApJ Letters, in press 7 pages, 4 figures (Fig. 4 added), 1 tabl

Alternating offer bargaining experiments with varying institutional details

The game theoretic prediction for alternating offer bargaining depends crucially on how 'the pie' changes over time, and whether the proposer in a given round has ultimatum power. We study experimentally eight such bargaining games. Each game is once repeated before moving on to the next one what defines a cycle of altogether 16 successive plays. Participants play three such cycles. There are no major experience effects but strong and reliable effects of anticipated rule changes. The latter, however, are not due to strategic considerations but rather to the social norms of fairness and efficiency

On saving and investing: An experimental study of intertemporal decision making in a complex stochastic environment

The experimental situation presents a complex stochastic intertemporal allocation problem. First, two initial chance moves select one of three possible termination probabilities which then determines whether life lasts 3,4,5, or 6 periods. Compared to Anderhub et al. (1997) participants are allowed to invest into a risky, but profitable asset. We investigate whether the willingness to invest can help to explain saving behavior, i.e. experimentally observed intertemporal decision making

Long-term work contracts versus sequential spot markets: Experimental evidence on firm-specific investment

Dismissal rules, i.e. legally enforced long term contracts, have beem defended against criticism for, among other things, providing efficient incentives to invest in relationship specific skills. However, in many situations efficient investment can also be attained by spot contracts. We replicate such a situation with our experimental design based on a simple two period game, involving the choke of the contract; length by the principal and an investment choke by the agent. In contrast to the game theoretic predictions, we find that investment of the worker and length of contract; are strictly positively correlated. We interpret our finding as an indication for a perceived market risk due to other players' actions although the model is fully deterministic. This could imply a behaviorally relevant difference between contract and market administered incentives

An experimental study of the repeated trust game with incomplete information

In the trust game first player 1 decides between non-cooperation or trust in reciprocity and then, in the latter case, player 2 between exploiting player 1 or rewarding him. In our experiment, player 2 can be a notorically rewarding player (this type is implemented as a robot strategy) or a human participant who may decide opportunistically. To allow for reputation formation, this game is played repeatedly. Learning can be analysed since participants play successively several repeated games with changed partners. In our computerized experiment, participants can explicitly rely on mixed strategies which allows testing the qualitative and quantitative aspects of reputation equilibria also at an individual level