Bargaining Outcomes as the Result of Coordinated Expectations: An Experimental Study of Sequential Bargaining

Experimental studies of two-person sequential bargaining demonstrate that the concept of subgame perfection is not a reliable point predictor of actual behavior. Alternative explanations argue that 1) fairness influences outcomes and 2) that bargainer expectations matter and are likely not to be coordinated at the outset. This paper examines the process by which bargainers in two-person dyads coordinate their expectations on a bargaining convention and how this convention is supported by the seemingly empty threat of rejecting positive but small subgame perfect offers. To organize the data from this experiment, we develop a Markov model of adaptive expectations and bounded rationality. The model predicts actual behavior quite closely.Sequential Bargaining, Experiment, Convention, Fairness, Finite Markov Chain, Bounded Rationality

The Demand for Punishment

While many experiments demonstrate that the actual behavior is different than predicted behavior, they have not shown that economic reasoning is necessarily incorrect. Instead, these experiments illustrate that the problem with homo economicus is that his preferences have been mis-specified. Modeled with social preferences, agents who forgo material gains can often be called rational. The current experiment illustrates this point with an example. Assuming self-interested agents, punishment is not credible in social dilemmas, yet people are often willing to incur costs to punish free riders. Despite this seeming irrationality, we show that these same people react to changes in the price of punishing and income as if punishment was an ordinary and normal good.public good, social dilemma, experiment, punishment

When In Rome: Conformity and the Provision of Public Goods

We ask whether conformity, copying the most observed behavior in a population, can affect free riding in a public goods situation. Our model suggests that, if free riding is sufficiently frequent at the start of a public goods game, conformity will increase the growth rate of free riding. We confirm this prediction in the experimental lab by showing that more free riding occurs when players have information about the distribution of contributions than when players know only the aggregate contribution level. As a stricter test, we econometrically estimate the dynamic on which the model is based and find that, controlling for the payoff incentive to free ride, players react significantly to the number of free riders in their groups. Further, conformity is significantly stronger when players have more information about the choices of others.conformity, public good, social dilemma, experiment, replicator dynamic

Punishing Free Riders: how group size affects mutual monitoring and the provision of public goods

Standard game theoretic models predict, based on subgame perfection, that public goods will not be provided even if agents are allowed to monitor free riders at some cost. Further, because punishment is not credible in these environments, this prediction is invariant to the size of groups. However, there is now substantial evidence that people are reciprocally motivated and will punish free riders, regardless of the material costs of doing so. To examine the implications of reciprocally-minded agents, we simulate an environment populated with the behavioral strategies often seen in the experimental lab and use the simulation to develop hypotheses that are more specific about why group size should matter when sanctions are allowed. We then test these hypotheses experimentally using the voluntary contribution mechanism. We examine whether the effect of group members or if information about other group members is what is important. We find large groups provide public goods at levels no less than small groups because punishment does not fall in large groups. However, hindrances to monitoring do reduce the provision of the public good.Public Goods, Mutual Monitoring, Group Soze, Experiment, Simulation

Do Social Preferences Increase Productivity? Field experimental evidence from fishermen in Toyama Bay

We provide a reason for the wider economics profession to take social preferences, a concern for the outcomes achieved by other reference agents, seriously. Although we show that student measures of social preference elicited in an experiment have little external validity when compared to measures obtained from a field experiment with a population of participants who face a social dilemma in their daily lives (i.e., team production), we also find strong links between the social preferences of our field participants and their productivity at work

Social Reciprocity

We conduct a survey and find that 47% of respondents state they would sanction free riders in a team production scenario even though the respondent was not personally affected and no direct benefits could be expected to follow an intervention. To understand this phenomenon, we define social reciprocity as the act of demonstrating ones disapproval, at some personal cost, for the violation of a widely-held norm (for example, don’t free ride). Social reciprocity differs from reciprocity because social reciprocators punish all norm violators, regardless of group affiliation or whether or not the punisher bears the costs. Social reciprocity also differs from altruism because, while the latter is an outcome-oriented act benefiting someone else, the former is a triggered response not conditioned on future outcomes. To test the robustness of our survey results, we run a public goods experiment that allows players to punish each other. The experiment confirms the existence of social reciprocity and additionally demonstrates that more socially efficient outcomes arise when reciprocity can be expressed socially. Further we find that most subjects who punish do so to discipline transgressors and helping others is largely a positive externality. Finally, to provide some theoretical foundations for social reciprocity, we show that generalized punishment norms survive in one of the two stable equilibria of an evolutionary public goods game with selection drift.reciprocity, norm, experiment, public good, learning, evolution

No Switchbacks: Rethinking Aspiration-Based Dynamics in the Ultimatum Game

The stylized facts of ultimatum bargaining in the experimental lab are that offers tend to be near an equal split of the surplus and low, near perfect offers are routinely rejected. Bimmore et al (1995) use aspiration-based evolutionary dynamics to model the evolution of fair play in a binary choice version of this game, and show that incredible threats to reject low offers persist in equilibrium. We focus on two possible extensions of this analysis: (1) the model makes assumptions about agent motivations (aspiration levels) and the structure of the game (binary strategy space) that have not yet been tested experimentally, and (2) the standard dynamic is based on the problematic assumption that unhappy games who switch strategies may end up using the same strategy that was just rejected. To examine the implications of not allowing agents to “switch back” to their original strategy, we develop a “no switchback dynamic” and run a new, binary choice, experiment with induced aspirations. We find that the resulting dynamic predicts the evolution of play better than the standard dynamic and that aspirations are a significant motivator for our participants.ultimatum game, learning, aspirations, switchbacks, replicator dynamics

Do Social PreferencesIncrease Productivity? Field experimental evidence from fishermen in Toyoma Bay

We provide a reason for the wider economics profession to take social preferences, a concern for the outcomes achieved by other reference agents, seriously. Although, we show that student measures of social preference elicited in an experiment have little external validity when compared to measures obtained from a field experiment with a population of participants who face a social dilemma in their daily lives (i.e. team production), we do find strong links between the social preferences of our field participants and their productivity at work. We also find that the stock of social preferences evolves endogeously with respect to how widely team production is utilized.Field experiment, social preference, income pooling, productivity

Why Punish: Social Reciprocity and the Enforcement of Prosocial Norms

Recently economists have become interested in why people who face social dilemmas in the experimental lab use the seemingly incredible threat of punishment to deter free riding. Three theories have evolved to explain punishment. We survey each theory and se behavioral data from surveys and experiments to show that the theory called social reciprocity in which people punish norm violators indiscriminately explains punishment best. We also show that social reciprocity can evolve in a population of free riders and contributors if the initial conditions are favorable.social dilemma, public good, punishment, reciprocity, norm, evolutionary game theory, experiment

Competitive Work Environments and Social Preferences: Field experimental evidence from a japanese fishing community

Models of job tournaments and competitive workplaces more generally predict that while individual effort may increase as competition intensifies between workers, the incentive for workers to cooperate with each other diminishes. We report on a field experiment conducted with workers from a fishing community in Toyama Bay, Japan. Our participants are employed in three different aspects of fishing. The first group are fishermen, the second group are fish wholesalers (or traders), and the third group are staff at the local fishing coop. Although our participants have much in common (e.g., their common relationship to the local fishery and the fact that they all live in the same community), we argue that they are exposed to different amounts of competition on-the-job and that these differences explain differences in cooperation in our experiment. Specifically, fisherman and traders, who interact in more competitive environments are significantly less cooperative than coop staff who face little competition on the job. Further, after accounting for the possibility of personality-based selection, perceptions of competition faced on-the-job and the treatment effect of job incentives explain these difference in cooperation to a large extent.Field experiment, cooperation, social disapproval, social preference, competition, Japan, fishing