Bilateral communication in procurement auctions

We ask how buyers can make use of bilateral communication in a procurement setting with moral hazard. We focus on a setting where buyers and potential sellers can exchange cheap-talk messages before trading and where the seller is determined via a buyer-determined procurement auction. In this type of auction, buyers can freely choose among bidders based on bidders’ observable characteristics and the prices they ask for. In a controlled laboratory experiment, we find that buyers use free-form text messages to make requests and to reduce social distance. The relationship between the offers sellers make and the messages they send is mediated by buyers’ requests. But, in general, buyers may increase their profits by choosing sellers who promise high quality or large profits. Furthermore, despite the cheap-talk nature of requests, buyers in our experiment increase their profits by specifically demanding high quality or large profits

Public-good experiments with large groups

Many of real-world public-goods are characterized by a marginal per capita return (MPCR) close to zero and have to be provided by large groups. Up until now, there is almost no evidence on how large groups facing a low MPCR behave in controlled public-good laboratory experiments involving financial incentives. Connecting four experimental laboratories located in four di¤erent German universities via Internet, we are able to run such experiments. In ad-dition to the group size (60 and 100 subjects), we vary the MPCR which is as small as 0:02 or 0:04. Our data reveal a strong MPCR effect, but almost no group-size e¤ect. Our data demonstrates that, even in large groups and for low MPCRs, considerable contributions to public goods can be expected. Interestingly, the contribution patterns observed in large and very small groups are very similar. To the best of our knowledge, this study is the first one that includes large-group laboratory experiments with a small MPCR under conditions comparable to previous small-group standard public-good experiments

Still different after all these years: Solidarity behavior in East and West Germany

Using data from laboratory experiments, we find that East Germans show consistently less solidarity than West Germans; there has been no convergence in the 20 years after the reunification. While it has recently been estimated that political values converge 20 to 40 years after the reunification (Alesina and Fuchs-Schundeln, 2007), we conclude from our findings that social behavior changes more slowly than political values. We hypothesize that this is due to complementarities involved in individual social behavior and the necessity to coordinate on social norms on the society level. (C) 2011 Elsevier B.V. All rights reserved

The dynamics of behavior in modified dictator games

<div><p>We investigate the dynamics of individual pro-social behavior over time. The dynamics are tested by running the same experiment with the same subjects at several points in time. To exclude learning and reputation building, we employ non-strategic decision tasks and a sequential prisoners-dilemma as a control treatment. In the first wave, pro-social concerns explain a high share of individual decisions. Pro-social decisions decrease over time, however. In the final wave, most decisions can be accounted for by assuming pure selfishness. Stable behavior in the sense that subjects stick to their decisions over time is observed predominantly for purely selfish subjects. We offer two explanation for our results: diminishing experimenter demand effects and moral self-licensing.</p></div

Sequence of play.

<p>Sequence of play.</p

Hurdle model on the amount taken from player B.

<p>Hurdle model on the amount taken from player B.</p

Payoffs in the two prisoner’s dilemma games [<i>π</i>_<i>B</i>, <i>π</i>_<i>A</i>].

<p>Payoffs in the two prisoner’s dilemma games [<i>π</i>_<i>B</i>, <i>π</i>_<i>A</i>].</p

THE EFFECTS OF INTRODUCING MIXED PAYMENT SYSTEMS FOR PHYSICIANS: EXPERIMENTAL EVIDENCE

Mixed payment systems have become a prominent alternative to paying physicians through fee-for-service and capitation. While theory shows mixed payment systems to be superior, causal effects on physicians' behavior when introducing mixed systems are not well understood empirically. We systematically analyze the influence of fee-for-service, capitation, and mixed payment systems on physicians' service provision. In a controlled laboratory setting, we implement an exogenous variation of the payment method. Medical and non-medical students in the role of physicians in the lab (N = 213) choose quantities of medical services affecting patients' health outside the lab. Behavioral data reveal significant overprovision of medical services under fee-for-service and significant underprovision under capitation, although less than predicted when assuming profit maximization. Introducing mixed payment systems significantly reduces deviations from patient-optimal treatment. Although medical students tend to be more patient regarding, our results hold for both medical and non-medical students. Responses to incentive systems can be explained by a behavioral model capturing individual altruism. In particular, we find support that altruism plays a role in service provision and can partially mitigate agency problems, but altruism is heterogeneous in the population. Copyright (C) 2015 John Wiley & Sons, Ltd