How does the effect of pre-play suggestions vary with group size? Experimental evidence from a threshold public-good game

Numerous studies have examined factors influencing the likelihood of cooperative outcomes in nonzero-sum games, but there has been little study of the interaction between two of the most important: group size and pre-play cheap talk. We report results from an experiment in which groups of size between 2 and 15 play a one-shot multi-player threshold public-good game. In our random leader treatment, all group members select a suggestion (e.g., “Everyone should choose X”), with one randomly chosen to be broadcast to the group. In a choice only treatment, subjects choose suggestions but none is sent, and in a baseline treatment, there are no suggestions at all. We find a negative interaction between group size and this kind of communication: the beneficial effect of both suggestions overall and cooperative suggestions on cooperation, cooperative outcomes, and payoffs decreases sharply as the group size increases. We find a similar negative interaction in a follow-up treatment in which all group members’ suggestions are broadcast to the group. Our results suggest that care should be taken in generalising conclusions from small-group experiments to large groups.     

Perceived trade-off between education and sports career: evidence from professional football

To explore the attitudes towards risky career choices of young people in highly competitive environments, we surveyed almost 1000 football players in the youth academies of German professional clubs (Bundesliga), who must generally decide early in their careers whether or not to risk quitting school to focus solely on a professional football career. Based on the survey responses, we empirically analysed which factors influence these youths’ tendencies to choose a high-risk career option over a lower risk one. Our results seem to indicate that such risk taking in competitive environments can be explained by potential benefits expected from this decision, as well as judgments about the likelihood of achieving the desired career. Risk attitudes towards career choices vary by differences in individuals’ estimates of the potential benefits and in particular, in their own assessments of the likelihood of success, which is an important driver of risk acceptance. We also found that opportunity cost considerations influence risk acceptance: the better the low-risk option, the less willing the individual to give it up for a high-risk alternative. In addition, both national origin and level of cultural integration play a role in attitudes towards risky career choices, with reductions in the latter increasing the risk premium of quitting school.     

Does peer group size influence social preferences and risk taking?

This paper examines whether the ex post relative payoffs of peers as well as the size of the peer group impact an agent's willingness to take risks. For example, persons in a flood plain may be less likely to purchase flood insurance if their neighbors also refrain from purchasing. We generalize the Fehr‐Schmidt (1999) model to allow the intensity of the social preferences to vary with the size of the peer group. Our experiment tests whether subjects are more or less likely to choose a lottery over a fixed payment when others have been assigned either the same lottery or the fixed payment. Using both between and within subject designs, we find risk‐taking behaviour is not responsive to the risks faced by others regardless of the size of peer group.     

Positional income concerns and personality: evidence from Germany

Positional income concerns (PIC) strongly influence economic behaviour and life outcomes. However, very little is known about the underlying heterogeneity regarding their importance across individuals on the one hand and across different reference groups on the other. Our analysis builds on representative survey data reporting PIC vis-à-vis seven reference groups, allowing us to identify marked heterogeneity both between and within subjects. We present evidence about who (in terms of personality) compares to whom (in terms of reference group).     

Comparing group and individual decision-making in risky environments

This dissertation completes salient group and individual experiments in two environments that differ as to whether or not an evaluative criterion exists to judge subject performance. The first environment is lottery-choice. No such criterion exists in a lottery-choice environment. Subjects base their decisions on their preference for risk. A lottery-choice experiment consists of a menu of paired lottery choices structured so that the crossover point to the high-risk lottery can be used to infer the degree of risk aversion. The results show a significant interaction exists between subject composition and lottery winning-percentage. Groups are more likely than individuals to choose the “safe” lottery in the lowest winning-percentages, but less likely to choose the “safe” lottery in the highest winning-percentages. This effect is also present in the sequenced experiment. Further, the sequenced experiment shows that group discussion results in a significant increase in the group’s risk aversion from the average risk preference of its members. Finally, the sequenced experiment shows making a decision in the group phase has an immediate impact on subsequent individual decisions compared to the subject’s initial decisions. The second environment is resource allocation. A resource allocation experiment consists of subjects making repeated decisions of how to divide an endowment into two assets, one of which the payoff is unknown. An evaluative criterion to the resource allocation problem exists, as there is a specific allocation that maximizes payoffs. However, subjects must learn the solution through search. Experimental results show: 1) group performance in the resource allocation experiment is not significantly different than individuals; 2) the predictions from a local search model are more consistent with group decisions than the predictions from a global search model; and 3) group risk preferences elicited through a separate lottery-choice experiment are not indicative of their performance in the resource allocation experiment. Ph.D. Dissertation, Completed at Indiana University, Bloomington Dissertation Committee: Chair–Professor Arlington W. Williams, Indiana University, Bloomington Assistant Professor Hugh Kelley, Indiana University, Bloomington Associate Professor Susan K. Laury, Georgia State University Professor James M. Walker, Indiana University, Bloomington     

Cooperation in a risky world

We offer a novel investigation of the effect of environmental risk on cooperation in the Voluntary Contribution Mechanism. Our baseline is the standard setting, in which the personal return from the public good is deterministic, homogeneous, and publicly known. Our experimental treatments alter this classic design by making the marginal per capita return from the public good probabilistic. In the homogeneous risk (HomR) treatment, the random draw is made for the whole group, whereas in the heterogeneous risk (HetR) treatment, this happens independently for each group member. Our hypothesis is that different environmental risks may differently affect the ex post payoff inequalities, so that other‐regarding preferences (inequality aversion) may generate higher contributions in HomR than in HetR. Our main result is that the environmental risk does not affect the patterns of cooperation either in the one‐shot or in the finitely repeated version of the game. This suggests that the standard experimental methodology provides a robust and conservative measure of human cooperation.     

Unsafe sex,AIDS and development

The AIDS-fighting communities have spent their limited resource on improving people’s awareness of the risk of contracting AIDS, and yet these programs have not resulted in sustained behavior change. This paper offers a possible explanation of why agents in poor countries choose to engage in more unsafe sexual activities when they are perfectly cognizant of the risk involved. It is shown that agents may rationally choose to do so when they are poor, since future is not attractive due to poverty and agents care more about current-period utility. Our results indicate that safe sexual practice is essentially a “normal good” and that development may be key to reduce the HIV infectivity by modifying agents’ sexual behavior. The model is then extended to consider the role of public health expenditure. We find that the relationship between protected sexual activity and development is no longer monotonic: unsafe sexual activity may increase slightly after a critical level of development has been reached. Finally, we examine the impacts of AIDS on development by considering individual’s saving decision. It is shown that agents tend to save more and accumulate more capital when economy grows.     

Past experience of uncertainty affects risk aversion

In an experiment with more than 500 participants we study how past experience of uncertainty (imperfect knowledge of the state space) affects risk preferences. Participants in our experiment choose between a sure outcome and a lottery in 32 periods. All treatments are exactly identical in periods 17–32 but differ in periods 1–16. In the early periods of the risk treatment there is perfect information about the lottery; in the ambiguity Treatment participants perfectly know the outcome space but not the associated probabilities; in the unawareness treatment participants have imperfect knowledge about both outcomes and probabilities. We observe strong treatment effects on behavior in periods 17–32. In particular, participants who have been exposed to an environment with very imperfect knowledge of the state space subsequently choose lotteries with high (low) variance less (more) often compared to other participants. Estimating individual risk attitudes from choices in periods 17–32 we find that the distribution of risk attitude parameters across our treatments can be ranked in terms of first order stochastic dominance. Our results show how exposure to environments with different degrees of uncertainty can affect individuals’ subsequent risk-taking behavior.     

Risk,trust, and altruism in genetic data sharing

How does concern about genetic data privacy compare with other concerns? We conduct behavioral experiments to compare risk attitudes towards sharing genetic data with a healthcare provider with risk attitudes towards sharing financial data with a money manager. Both scenarios involve identical decisions and monetary stakes, permitting us to focus on how the framing of data sharing influences attitudes. To delve deeper into individual motivations to share data, we provide treatments that study how data sharers' altruism and trust affect their decisions. Our findings (with 162 subjects) indicate that individuals are more willing to risk a loss to privacy of genetic data (for an anticipated return framed as health benefits) than they are to risk loss of financial data (for an anticipated return in financial benefits). We also find that 50%–60% of data recipients choose to protect another person's data, with no significant differences between frames.     

Rotating group representatives and group members’ requests in repeated public goods game

ABSTRACT

This study investigated the effect of group representatives on contribution behaviour in response to group members’ requests in repeated public goods games. Data came from 135 students in 15 groups enrolled in the experiment, grouped in the following treatments: no group representatives (NR, NRG) and group representatives (R1, R2). We also tested initial requests wherein the group members’ initial requests (i.e. NRG, R2) mediated the positive relationship between individual-level contribution preferences and group contributions. We used a fixed-effects GLS regression and IV regression to analyse the effect of group representatives and group members’ requests. The results indicated the following: (a) rotating group representative/group members’ requests was related to group contributions at the session (within-members) and group (between-group) levels; (b) the reactions to members’ requests positively predicted group contributions; (c) subjects in the no group representatives treatment formed their requests by relying more on previous group contributions than subjects in the group representatives treatment, who relied more on the previous group members’ requests; and (d) the initial requests explained long-term contribution levels, which resulted in variations in group contributions observed between the NRG and R2 treatments. Our findings highlight the role of rotating group representatives in stimulating cooperation among members, while group members’ requests impel individuals to make contribution decisions at the group level.     

The optimality of nominal contracts

Summary. This paper presents a model in which agents choose to use money as a medium of exchange, a means of payment, and a unit of account. The paper defines conditions under which nominal contracts, promising future payment of a fixed number of units of fiat money, prove to be the optimal contract form in the presence of either relative or aggregate price risk. When relative prices are random, nominal contracts are optimal if individuals have ex ante similar preferences over future consumption. When the aggregate price level is random, whether from shocks to the money supply or aggregate output, nominal contracts (perhaps coupled with equity contracts) lead to optimal risk-sharing if individuals have the same degree of relative risk aversion. Finally, nominal contracts may be optimal if the repayment of contracts is subject to a binding cash-in-advance constraint. In this case, a contingent contract increases the risk of holding excessive cash balances. Received: March 29, 1996; revised version: February 25, 1997     

Liberal constitutionalism,constitutional liberalism and democracy

The tension that is often seen to exist between the ideals of liberalism and of democracy is examined in this paper in light of the distinction between two liberal outlooks at constitutional regimes, namely, on the one side, a liberal constitutionalism that focuses on the need to provide institutional safeguards of individual liberty as private autonomy and, on the other hand, a constitutional liberalism that focuses on the need to respect the freedom of individuals to choose the constitutional environment in which they wish to live. It is argued that a liberalism that consistently extends its fundamental ideal of individual sovereignty to the level of constitutional choice can be reconciled with the basic democratic ideal of citizen sovereignty.     

Commuters route choice behaviour

The paper reports laboratory experiments with a two route choice scenario. In each session 18 subjects had to choose between a main road M and a side road S. The capacity of M was larger. Feedback was given in treatment I only on the subjects' own travel time and in treatment II on travel time for M and S. The main results are as follows:

• Mean numbers on M and S are near to pure equilibrium.

• Fluctuations persist until the end of the sessions.

• The total number of changes is significantly greater in treatment I.

• Subjects' road changes and payoffs are negatively correlated.

• A direct response mode results in more changes for bad payoffs whereas a contrary response mode shows opposite reactions.

• Simulations of an extended payoff sum learning model fits the main results of the statistical evaluation of the data.

Individual and Group Behavior in the Ultimatum Game: Are Groups More “Rational” Players?

This article reports two experiments that compared the standard ultimatum game played by individuals with the same game played by three-person groups. In the group treatment, the members of the allocating group conducted a brief, face-to-face discussion in order to decide, as a group, on a proposed division, whereas the members of recipient group held a discussion on whether to accept or reject the proposal. If the proposal was accepted, each group member received an equal share of his group's payoff (the pie in the group condition was three times that in the individual condition). In both experiments, groups offered less than individuals. But as indicated by the low rejection rate in both treatments, groups were also willing to accept less.     

Lab and framed lab versus natural experiments: Evidence from a risky choice experiment

Some recent papers have studied data from TV game shows to examine the behaviour of individuals towards risk. It is generally agreed that data from these shows are useful in detecting individual risk aversion in the field, with both “real life” subjects and incentives. Field experiments also include some interesting reality features that could affect individuals’ behaviour and possibly lead to different findings. This paper aims at investigating lab versus field evidence in risk taking attitudes, especially controlling for framing effects. To assess whether the behaviour of subjects in the field is consistent with that of experimental subjects, we designed an experiment to mimic (with experimental rewards and subjects) the rules of a well-known Italian TV game show, Affari Tuoi, in two different settings: a traditional lab setting, where the game was played individually (109 subjects) (Treatment 1); and a framed lab, in which the experiment was replicated in the Italian public television (RAI) studio where the show was actually recorded, with a smaller sample of undergraduate students (33) and in the presence of an audience (Treatment 2). Our comparison between the two different settings aims at establishing whether the presence of an audience, or of a situation that reproduces the stress that contestants must experience in the TV studio, can affect experimental subjects’ choices. We did not find any significant evidence of framing effects: students behave in a similar way in the two lab settings, responding essentially to incentives. Comparing the risk attitudes shown by experimental subjects in the two lab treatments with those exhibited by the contestants in the field, we found that contestants in the TV show are generally more risk averse than students in the lab.     

Voluntary Contributions to a Mutual Insurance Pool

We study mutual‐aid games in which individuals choose to contribute to an informal mutual insurance pool. Individual coverage is determined by the aggregate level of contributions and a sharing rule. We analyze theoretically and experimentally the (ex ante) efficiency of equal and contribution‐based coverage. The equal coverage mechanism leads to a unique no‐insurance equilibrium while contribution‐based coverage develops multiple equilibria and improves efficiency. Experimentally, the latter treatment reduces the amount of transfers from high contributors to low contributors and generates a “dual interior equilibrium.” That dual equilibrium is consistent with the co‐existence of different prior norms which correspond to notable equilibria derived in the theory. This results in asymmetric outcomes with a majority of high contributors less than fully reimbursing the global losses and a significant minority of low contributors less than fully defecting. Such behavioral heterogeneity may be attributed to risk attitudes (risk tolerance vs risk aversion) which is natural in a risky context.     

Nudging Merit Goods: Conceptual,Normative, and Practical Connections

Abstract

Mainstream economics has traditionally maintained a respect for preferences and the choices that individuals make based on them. But recent advances in psychology and behavioral economics have led scholars and policy-maker to doubt if people make wise choices in their own interests. Based on this, libertarian paternalists endorse choice interventions—nudges—designed to steer people to decisions that will better promote their interests. However, the complex, multifaceted, and subjective nature of interests implies that policy-makers are imposing externally chosen interests for people’s own when designing nudges. In this sense, policy-makers are treating the interests they choose to advance like merit goods as described by Richard Musgrave, goals or ends that are explicitly judged by policy-makers to be worth advancing even if they are not ranked highly or chosen consistently by individuals themselves. This paper will make explicit the conceptual and normative connections between nudges and merit goods, arguing that nudges can be considered delivery mechanisms for merit goods, and recommending that libertarian paternalists abandon their claim to be advancing people’s true interests and instead adopt the objective theories of good used to justify merit goods.     

Risk aversion and framing effects

We present a new experimental evidence of how framing affects decisions in the context of a lottery choice experiment for measuring risk aversion. We investigate framing effects by replicating the Holt and Laury’s (Am. Econ. Rev. 92:1644–1655, 2002) procedure for measuring risk aversion under various frames. We first examine treatments where participants are confronted with the 10 decisions to be made either simultaneously or sequentially. The second treatment variable is the order of appearance of the ten lottery pairs. Probabilities of winning are ranked either in increasing, decreasing, or in random order. Lastly, payoffs were increased by a factor of ten in additional treatments. The rate of inconsistencies was significantly higher in sequential than in simultaneous treatment, in increasing and random than in decreasing treatment. Both experience and salient incentives induce a dramatic decrease in inconsistent behaviors. On the other hand, risk aversion was significantly higher in sequential than in simultaneous treatment, in decreasing and random than in increasing treatment, in high than in low payoff condition. These findings suggest that subjects use available information which has no value for normative theories, like throwing a glance at the whole connected set of pairwise choices before making each decision in a connected set of lottery pairs.     

Risk Aversion and International Markets: Does Asset Trade Smooth Real Income?*

In a two-country model, complete asset markets do not guarantee that individuals will choose to eliminate all (diverifiable) risk in aggregate consumption. the presence of nontraded goods forces individuals to choose between reducing uncertainty in aggregate consumption and in the composition between traded and nontraded goods. This choice depends on a comparison of the standard coefficient of relative risk aversion with a second type of risk aversion that becomes relevant when nontraded goods are present, one that captures aversion to risk in composition. Regardless of the decision made, asset trade always reduces the risk premium.