Evolutionary games on graphs

Over the last 25 years, more than a hundred dictator game experiments have been published. This meta study summarises the evidence. Exploiting the fact that most experiments had to fix parameters they did not intend to test, in multiple regression the meta study is able to assess the effect of single manipulations, controlling for a host of alternative explanatory factors. The resulting rich dataset also provides a testbed for comparing alternative specifications of the statistical model for analysing dictator game data. It shows how Tobit models (assuming that dictators would even want to take money) and hurdle models (assuming that the decision to give a positive amount is separate from the choice of amount, conditional on giving) provide additional insights.

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Dictator games: a meta study

I survey the literature post Ledyard (Handbook of Experimental Economics, ed. by J. Kagel, A. Roth, Chap. 2, Princeton, Princeton University Press, 1995) on three related issues in linear public goods experiments: (1) conditional cooperation; (2) the role of costly monetary punishments in sustaining cooperation and (3) the sustenance of cooperation via means other than such punishments. Many participants in laboratory public goods experiments are “conditional cooperators” whose contributions to the public good are positively correlated with their beliefs about the average group contribution. Conditional cooperators are often able to sustain high contributions to the public good through costly monetary punishment of free-riders but also by other mechanisms such as expressions of disapproval, advice giving and assortative matching.

https://www.cepr.org/sites/default/files/events/papers/796_CHAUDHURI.pdf

Sustaining cooperation in laboratory public goods experiments: a selective survey of the literature

One lingering puzzle is why voluntary contribu tions to public goods decline over time in experimental and real-w orld settings. We show that the decl ine of cooperation is driven by individual preferences for im perfect conditional cooperation. Many people’s desire to contribute less than oth ers, rather than changing beliefs of what others will contr ibute over time or people’s heterogeneity in preferences makes voluntary cooperation fragile. Universal free riding thus even tually emerges, despite the fact tha t m ost peop le a re not selfis h. (JEL C91, C72, H41, D64)

/pdf/social-preferences-beliefs-and-the-dynamics-of-free-riding-5djmyntr9e.pdf

Social Preferences, Beliefs, and the Dynamics of Free Riding in Public Goods Experiments

In this paper, we present a first survey of the literature regarding whether the strategy method, in which a responder makes conditional decisions for each possible information set, leads to different experimental results than does the more standard direct-response method, in which the responder learns the action of the first mover and then chooses a response. Of the twenty-nine existing comparisons, sixteen find no difference, while four do find differences, and nine comparisons find mixed evidence. We also find some indications about the underlying determinants of when the two methods lead to different responses. For example, it appears that levels of punishment are substantially lower with the strategy method. In addition, it also appears that difference across these elicitation methods are more likely when people make fewer contingent choices. Finally, in no case do we find that a treatment effect found with the strategy method is not observed with the direct-response method.

/pdf/the-strategy-versus-the-direct-response-method-a-first-q7snzbqvmp.pdf

The strategy versus the direct-response method: a first survey of experimental comparisons

. We examine how communication affects cooperation with the help of seven standard public goods experiments that only differ with respect to the medium of pre-play communication. Our treatments include bidirectional and unidirectional communication via (mostly electronic) auditory and/or visual channels. The results suggest that successful cooperation is attributable to the opportunity of ‘coordinating’ behavior in the communication phase. Furthermore, both the level and the stability of cooperation significantly interact with the communication medium, even though the content of communication is remarkably similar across the communication treatments.

The Effect of Communication Media on Cooperation

In recent years, experimental economists have discovered that people exhibit different patterns of cooperative behavior. This paper presents findings from a face-to-face experiment that analyzed whether individuals who possess a willingness to cooperate can credibly signal it and whether it is recognizable by the partner. Results revealed that both capabilities, signaling and recognizing, depend upon the individual’s propensity to cooperate. © 2002 Elsevier Science B.V. All rights reserved.

Identifying cooperative behavior: some experimental results in a prisoner's dilemma game

In this paper, the strategy method's impact on behavior in sequential bargaining games is investigated. Besides the decision procedure (hot versus cold), we varied the second mover punishment costs (high versus low). Significant impacts of both treatment variables were observed. For example, second movers punished significantly more often in the hot version of the low cost game. Furthermore, first mover behavior was significantly different in the hot and cold versions of both games. In the hot games, first mover behavior suggests an expectation of decreased rewards and/or punishments from second movers. We observed, however, no decrease in reward and an increase in punishment. The hot cold variable only informs first movers that the decision procedure used by second movers has changed. Therefore, first mover behavior must be shaped by their perceived assessment concerning how second movers make decisions. We argue that first mover behavior can be explained by the interaction of two well-known psychological effects: the consensus and positive self-image effects.

https://idv.sinica.edu.tw/cly/Text%20links/A11-2003.pdf

The Hot Versus Cold Effect in a Simple Bargaining Experiment

This paper puts three of the most prominent specifications of ‘other-regarding’ preferences to the experimental test, namely the theories developed by Charness and Rabin, by Fehr and Schmidt, and by Andreoni and Miller. In a series of experiments based on various dictator and prisoner’s dilemma games, we try to uncover which of these concepts, or the classical selfishapproach, is able to explain most of our experimental findings. The experiments are special with regard to two aspects: First, we investigate the consistency of individual behavior within and across different classes of games. Second, we analyze the stability of individual behavior over time by running the same experiments on the same subjects at several points in time.
Our results demonstrate that in the first wave of experiments, all theories of other-regarding preferences explain a high share of individual decisions. Other-regarding preferences seem to wash out over time, however. In the final wave, it is the classical theory of selfish behaviorthat delivers the best explanation. Stable behavior over time is observed only for subjects, who behave strictly selfish. Most subjects behave consistently with regard to at least one of the theories within the same class of games, but are much less consistent across games.

http://www.ww.uni-magdeburg.de/fwwdeka/femm/a2007_Dateien/2007_05.pdf

Jeannette Brosig

Papers

The Effect of Communication Media on Cooperation

Identifying cooperative behavior: some experimental results in a prisoner's dilemma game

The Hot Versus Cold Effect in a Simple Bargaining Experiment

Selfish in the End?:An Investigation of Consistency and Stability of individual Behavior

Entry decisions and bidding behavior in sequential first-price procurement auctions: An Experimental Study