Mobility and Cooperation: On the Run

In public goods experiments where subjects may change groups, we observe a continual flight of the more cooperative subjects away from the less cooperative ones. The less cooperative subjects attempt to enter cooperative groups in order to free-ride on their contributions. Lorsque les sujets peuvent changer de groupes dans les expériences sur les contributions volontaires aux biens publics, nous observons que les sujets plus coopératifs délaissent les sujets moins coopératifs. De plus, ces derniers essaient de joindre les groupes coopératifs pour profiter comme resquilleurs de leurs contributions.Public goods, Tiebout hypothesis, migration, experimental economics, Biens publics, hypothèse de Tiebout, migration, économie expérimentale

Auction Fever: Theory and Experimental Evidence

It is not a secret that certain auction formats yield on average higher prices than others. The phenomenon that dynamic auctions are more likely to elicit higher bids than static one-shot auctions is often associated with the term ''auction fever.'' On a psychological level, we consider the so-called pseudo-endowment effect as largely responsible for peoples’ tendency to submit higher bids, potentially amplified by the source-dependence effect. The phenomenon of auction fever is replicated in an experimental investigation of different auction formats within a private values framework where bidders have private but incomplete knowledge of their valuation for a hypothetical good. We suggest this assumption to be more realistic than definite private values, as assumed in the traditional IPV model. An additional experimental investigation within the traditional IPV framework does not either reveal any indication for the appearance of auction fever. On the basis of our experimental observations we present a model of reference-dependent utility theory that comprehends the phenomenon by assuming that bidders' reference points are shifted by the pseudo-endowment and the source-dependence effect.

Auctions, information, and new technologies

Auctions have been developed for economic transactions with asymmetric information and they are the simplest means of price determination for multilateral trading without "market makers." During the last years, new technologies gave a boost to the development and usage of innovative auction formats in several fields. We explore some of the new possibilities of applications and explain the differences to traditional auction formats. Furthermore, we demonstrate the potentialities of auctions concerning information gaining for the auctioneer as well as for the participating bidders

Conventions and Local Interaction Structures: Experimental Evidence

We present a set of experimental coordination games with a payoff-dominant and a risk-dominant Nash equilibrium. We examine how much local interaction structures affect players' strategy choices. Our three major observations are the following: First, local interaction with open neighborhoods along a circle leads to less coordination on the payoff-dominant equilibrium than interaction in closed neighborhoods (see also Keser, Ehrhart, and Berninghaus, Economics Letters, 1998). Second, when players are allocated around a circle, the neighborhood size has, in the long run, no effect on the players' strategy choices. Third, with the same neighborhood size, players allocated on a lattice tend less than players allocated around a circle to coordinate on the payoff-dominant equilibrium. This is true although the players are given exactly the same instructions. Nous présentons une série de jeux de coordination expérimentaux avec un équilibre de Nash qui est dominant par rapport au risque et un autre équilibre qui est dominant par rapport au gain. Nous examinons à quel degré des structures d'interaction locale ont une influence sur les choix de stratégies. Nos observations majeures sont les suivantes: Premièrement, l'interaction locale avec des voisinages autour d'un cercle implique moins de coordination sur l'équilibre qui est dominant par rapport au gain que l'interaction dans des voisinages fermés (voir aussi Keser, Ehrhart et Berninghaus, Economics Letters, 1998). Deuxièmement, quand les joueurs sont disposés en cercle, la taille du voisinage n'a pas d'effet à long terme sur les choix de stratégie par les joueurs. Troisièmement, avec la même taille de voisinage, des joueurs disposés en tore tendent moins que des joueurs disposés en cercle de se coordonner sur l'équilibre qui est dominant par rapport au gain. Cette différence est présente bien que les joueurs reçoivent exactement les mêmes instructions.Equilibrium selection, local interaction structures, experimental economics, Sélection des équilibres, structure d'interaction locale, économie expérimentale

Auctions, information, and new technologies

Auctions have been developed for economic transactions with asymmetric information and they are the simplest means of price determination for multilateral trading without "market makers." During the last years, new technologies gave a boost to the development and usage of innovative auction formats in several fields. We explore some of the new possibilities of applications and explain the differences to traditional auction formats. Furthermore, we demonstrate the potentialities of auctions concerning information gaining for the auctioneer as well as for the participating bidders

Myopically Forward-Looking Agents in a Network Formation Game: Theory and Experimental Evidence

A population of players is considered in which each agent can select her neighbors in order to play a 2x2 Hawk-Dove game with each of them. We design our experiment in continuous time where participants may change their Hawk-Dove action and/or their neighborhood at any point in time. We are interested in the resulting formation of networks and the action distributions. Compared with static Nash equilibrium (e.g., Berninghaus and Vogt, 2004, 2006; Bramoulle, Lopez-Pintado, Goyal, and Vega-Redondo, 2004) and social optimum as theoretical benchmark solutions, subjects seem to employ a more complex, forward-looking thinking. We develop an other benchmark solution, called one-step-ahead stability, that combines forward-looking belief formation with rational response and that fits the data much better.

How the auction design influences procurement prices: an experiment

The targeted design of auctions has to take behavioral regularities into account. This paper explores whether procurement auction formats can take advantage of bidders' willingness-to-pay-willingness-to-accept disparity. In a laboratory experiment, we compare four different second-price auction formats for procuring a good. The four formats are a sealed-bid auction and three different descending-clock auctions. We assume that a bidder's willingness-to-accept exceeds his willingness-to-pay and that, depending on the auction format, a bidder's reference-state shifts such that the bidder's perspective moves from a willingness-to-accept perspective towards a willingness-to-pay perspective, thus inducing aggressive bids. In line with the prediction, auction prices decline across the four formats. In particular, we observe the lowest prices in those two clock auction formats that, at every auction stage, select a bidder as the current leading bidder. We conclude that mechanisms influence the reference state and that auctions that foster reference-state shifts lead to lower payments for the buyer. These results support and generalize findings on sales auctions. However, not all of our findings on procurement auctions mirror findings on sales auctions. Bidders overbid in sealed-bid procurement auctions, which does not mirror the commonly observed overbidding in sealed-bid sales auctions

Design and regulation of balancing power auctions: an integrated market model approach

We present an integrated market model which considers the dependencies between the wholesale market and the highly regulated balancing power markets. This fosters the understanding of the mechanisms of these markets and, thus, allows the evaluation of the designs of these markets and their interplay. In contrast to existing literature, in our model the prices on the different markets are interdependent and endogenously determined, which also applies to the switch from inframarginal suppliers to extramarginal suppliers. Linked to this, the implementation of a specific assignment of the suppliers to the different markets is according to their production costs and their ability to provide balancing power. We prove the existence of a market equilibrium, analyze its outcome and contrast this with German market data. Based on this model, we assess design changes, partly stipulated by recent European regulation. This includes uniform pricing as a common settlement rule (effect: no truthful bidding in general), standardized prequalification criteria (promising measure for cost reduction), market flexibilization via “free energy bids” (no increased competition) and the alternative score “mixed-price rule” (no effect on the equilibrium)

Zum systematischen Vergleich von Rentenversicherung und Fondsentnahmeplänen unter dem Aspekt des Kapitalverzehrrisikos

A Systematic Comparison of Pension Annuities and Self-Annuitization under the Criterion of Capital Exhaustion is presented. The present paper further develops the paper of Albrecht/Goebel (SFB 504 discussion paper 00-31). New features are the evaluation of real estate funds, the consideration of real estate funds, the consideration of a 65 year old retiree and the consideration of the respective maximum and minimum funds for the evaluation period. The risk of self-annuitization is specified by the ruin probability of outliving one's wealth. It is assumed that the amount of withdrawal from the fund is equivalent to the constant annuity of the pension insurance contract. Again the determination of the ruin probability is the central objective of the paper.

Budget processes: Theory and experimental evidence

This paper studies budget processes, both theoretically and experimentally. We compare the outcomes of bottom-up and top-down budget processes. It is often presumed that a top-down budget process leads to a smaller overall budget than a bottom-up budget process. We show, using structurally induced equilibrium theory, that this may but need not be the case. To test the implications for budget processes of structurally induced equilibrium theory, we conduct a series of experiments. The evidence from these experiments supports the predictions of structurally induced equilibrium theory, both at the aggregate and at the individual subject level. --