In many contest situations, such as R&D competition and rent seeking, participants’ costs are private information. We report the results of an experimental study of bidding in contests under different information and symmetry conditions about players’ costs of effort. The theory predicts qualitatively different comparative statics between bids under complete and incomplete information in contests of two and more than two players. We use a 2×3 experimental design, (n=2, n=4)×(symmetric complete information, asymmetric complete information, incomplete information), to test the theoretical predictions. We find the comparative statics of bids across the information and symmetry conditions, and the qualitative differences in comparative statics across group sizes, in partial agreement with the theory.

Data created in a controlled laboratory setting are a relatively new phenomenon to economists. Traditional data analysis methods using either parametric or nonparametric tests are not necessarily the best option available to economists analyzing laboratory data. In 1935, Fisher proposed the randomization technique as an alternative data analysis method when examining treatment effects. The observed data are used to create a test statistic. Then treatment labels are shuffled across the data and the test statistic is recalculated. The original statistic can be ranked against all possible test statistics that can be generated by these data, and a p-value can be obtained. A Monte Carlo analysis of t-test, the Mann-Whitney U-test, and the exact randomization t-test is conducted. The exact randomization t-test compares favorably to the other two tests both in terms of size and power. Given the limited distributional assumptions necessary for implementation of the exact randomization test, these results suggest that experimental economists should consider using the exact randomization test more often.

In certain markets success may depend on how well participants anticipate the behavior of other participants who have varying amounts of experience. Understanding if and how people's behavior depends on competitors’ level of experience is important since in most markets participants have varying amounts of experience. Examining data from two new experimental studies similar to the beauty contest game first studied by Nagel (1995), the results indicate that (1) players with no experience behave the same against competitors with and without experience but (2) players quickly learn to condition their behavior on competitors’ experience level, causing (3) behavior to stop moving toward the equilibrium whenever new players enter the game and (4) experienced players to earn more money than less experienced players. The paper discusses the implications of the results for understanding and modeling behavior in markets in which participants have different amounts of experience.

In experimental economics there is a norm against using deception. But precisely what constitutes deception is unclear. While there is a consensus view that providing false information is not permitted, there are also “gray areas” with respect to practices that omit information or are misleading without an explicit lie being told. In this paper, we report the results of a large survey among experimental economists and students concerning various specific gray areas. We find that there is substantial heterogeneity across respondent choices. The data indicate a perception that costs and benefits matter, so that such practices might in fact be appropriate when the topic is important and there is no other way to gather data. Compared to researchers, students have different attitudes about some of the methods in the specific scenarios that we ask about. Few students express awareness of the no-deception policy at their schools. We also briefly discuss some potential alternatives to “gray-area” deception, primarily based on suggestions offered by respondents.

In the world of mutual funds management, responsibility for investment decisions is increasingly entrusted to small teams instead of individuals. Yet the effect of team decision-making in a market environment has never been studied in a controlled experiment. In this paper, we investigate the effect of team decision-making in an asset market experiment that has long been known to reliably generate price bubbles and crashes in markets populated by individuals. We find that this tendency is substantially reduced when each decision-making unit is instead a team of two. This holds across a broad spectrum of measures of the severity of mispricing, both under a continuous double-auction institution and in a call market. The result is not driven by reduced turnover due to time required for deliberation by teams, and continues to hold even when subjects are experienced. Our result also holds not only when our teams treatments are compared to the ‘narrow’ baseline provided by the corresponding individuals treatments, but also when compared more broadly to the results of the large body of previous research on markets of this kind.

We conduct a laboratory experiment in Kenya in which we elicit time and risk preference parameters from 494 participants, using convex time budgets and tightly controlling for transaction costs. Using the Kenyan mobile money system M-Pesa to make real-time transfers to subjects’ phones , we vary whether same-day payments are made immediately after the experimental session or at the close of the business day. We find strong evidence of present bias, with estimates of the present bias parameter ranging from 0.902 to 0.924—but only when same-day payments are made immediately after the experiment.

We report results from standard minimum-effort experiments conducted in Copenhagen (Denmark). Our subjects frequently coordinate on the Pareto-efficient equilibrium even in groups of six. This is in stark contrast to the previous literature, as we show in a detailed analysis of experiments which had the same design but were held in different countries. The subject-pool effect is substantiated by the finding that, the higher the share of Danish subjects in a group, the higher the minimum-effort levels. These findings suggest that the prevalent coordination failures previously observed are affected by significant subject-pool effects.

Pain is a highly salient and attention-demanding experience that motivates people to act. We investigated the effect of pain on decision making by delivering acute thermal pain to participants’ forearm while they made risky and intertemporal choices involving money. Participants (n = 107) were more risk seeking under pain than in a no-pain control condition when decisions involved gains but not when they involved equivalent losses. Pain also resulted in greater preference for immediate (smaller) over future (larger) monetary rewards. We interpret these results as a motivation to offset the aversive, pain-induced state, where monetary rewards become more appealing under pain than under no pain and when delivered sooner rather than later. Our findings add to the long-standing debate regarding the role of intuition and reflection in decision making.

A growing number of papers theoretically study the effects of introducing a preference signaling mechanism. However, the empirical literature has had difficulty proving a basic tenet, namely that an agent has more success when the agent uses a signal. This paper provides evidence based on a field experiment in an online dating market. Participants are randomly endowed with two or eight “virtual roses” that a participant can use for free to signal special interest when asking for a date. Our results show that, by sending a rose, a person can substantially increase the chance of the offer being accepted, and this positive effect is neither because the rose attracts attention from recipients nor because the rose is associated with unobserved quality. Furthermore, we find evidence that roses increase the total number of dates, instead of crowding out offers without roses attached. Despite the positive effect of sending roses, a substantial fraction of participants do not fully utilize their endowment of roses and even those who exhaust their endowment on average do not properly use their roses to maximize their dating success.

The house-money effect, understood as people’s tendency to be more daring with easily-gotten money, is a behavioral pattern that poses questions about the external validity of experiments in economics: to what extent do people behave in experiments like they would have in a real-life situation, given that they play with easily-gotten house money? We ran an economic experiment with 122 students to measure the house-money effect on their risk preferences. They received an amount of money with which they made risky decisions involving losses and gains; a randomly selected treatment group received the money 21 days in advance and a control group got it the day of the experiment. From a simple calculation we found that participants in the treatment group only spent on average approximately 35 % of their cash in advance. The data confirms the well documented results that men are more tolerant to risk than women, and that individuals in general are more risk tolerant towards losses than towards gains. With our preferred specification, we find a mean CRRA risk aversion coefficient of 0.34, with a standard deviation of 0.09. Furthermore, if subjects in the treatment group spent 35 % of the endowment their CRRA risk aversion coefficient is higher than that of the control group by approximately 0.3 standard deviations. We interpret this result as evidence of a small and indirect house money effect operating though the amount of the cash in advance that was actually spent. We conclude that the house money effect may play a small role in decisions under uncertainty, especially when involving losses. Our novel design, however, could be used for other domains of decision making both in the lab and for calibration of economic models used in micro and macroeconomics.

We study the effectiveness of costly rewards in mitigating excess extraction in a standard Common Pool Resource (CPR) game experiment. We implement two treatments. In the first, rewards are a pure transfer from one player to the other. In the second, the benefits of receiving a reward are higher than the cost of providing it. Referring to the latter as “net positive” rewards, we observe that these are used more frequently than transfer rewards, and that, unlike transfer rewards, they are effective in sustaining cooperation in the CPR game.

Asymmetric distribution of information, while omnipresent in real markets, is rarely considered in experimental financial markets. We present results from experiments where subjects endogenously choose between five information levels (four of them costly). We find that (i) uninformed traders earn the highest net returns, while average informed traders always perform worst even when information costs are not considered; (ii) over time traders learn to pick the most advantageous information levels (full information or no information); and (iii) market efficiency decreases with higher information costs. These results are mostly in line with the theoretical predictions of Grossman and Stiglitz (Am. Econ. Rev. 70:393-408, 1980) and provide additional insights that studies with only two information levels cannot deliver.

This paper reports results of a natural field experiment on the dictator game where subjects are unaware that they are participating in an experiment. Three other experiments explore, step by step, how laboratory behavior of students relates to field behavior of a general population. In all experiments, subjects display an equally high amount of pro-social behavior, whether they are students or not, participate in a laboratory or not, or are aware of their participating in an experiment or not. This paper shows that there are settings where laboratory behavior of students is predictive for field behavior of a general population.

A key question about human societies is how social norms of cooperation are enforced. Subjects who violate norms are often targeted by their peers for punishment. In an experiment with small teams we examine whether subjects treat punishment itself as a second-order public good. Results do not support this view and rather suggest a hard-wired taste for punishment; subjects are engaged in a cooperative task but ignore the public good characteristics of punishment.

We explore the relation between redistribution choices, source of income, and pre-redistribution inequality. Previous studies find that when income is earned through work there is less support for redistribution than when income is determined by luck. Using a lab experiment, we vary both the income-generating process (luck vs. performance) and the level of inequality (low vs. high). We find that an increase in inequality has less impact on redistribution choices when income is earned through performance than when income results from luck. This result is likely explained by individuals using income differences as a heuristic to infer relative deservingness. If people believe income inequality increases as a result of performance rather than luck, then they are likely to believe the poor deserve to stay poor and the rich deserve to stay rich.

Laboratory experiments have become a wide-spread tool in economic research. Yet, there is still doubt about how well the results from lab experiments generalize to other settings. In this paper, we investigate the self-selection process of potential subjects into the subject pool. We alter the recruitment email sent to first-year students, either mentioning the monetary reward associated with participation in experiments; or appealing to the importance of helping research; or both. We find that the sign-up rate drops by two-thirds if we do not mention monetary rewards. Appealing to subjects’ willingness to help research has no effect on sign-up. We then invite the so-recruited subjects to the laboratory to measure their pro-social and approval motivations using incentivized experiments. We do not find any differences between the groups, suggesting that neither adding an appeal to help research, nor mentioning monetary incentives affects the level of social preferences and approval seeking of experimental subjects.

ConG is software for conducting economic experiments in continuous and discrete time. It allows experimenters with limited programming experience to create a variety of strategic environments featuring rich visual feedback in continuous time and over continuous action spaces, as well as in discrete time or over discrete action spaces. Simple, easily edited input files give the experimenter considerable flexibility in specifying the strategic environment and visual feedback. Source code is modular and allows researchers with programming skills to create novel strategic environments and displays.

This paper reports the results of an experiment in which subjects had to buy real products in 5 different budget/price situations. Subjects were randomly drawn from the population of a medium-sized French city, and some of their socio-economic characteristics were recorded. We check the consistency of product choices with the Generalized Axiom of Revealed Preferences (GARP), and find that 29% of the subjects are GARP-inconsistent. This inconsistency rate is slightly lower than the ones found in comparable studies. A possible explanation for our lower rate of GARP violations might be that the subjects in our study were confronted with less budget/price situations. In looking for determinants of the GARP violations, we find that gender, the size of the household, the degree of switching between different products, and the times spent on performing experimental tasks have significant impacts on the probability of GARP-inconsistency.

Time pressure is a central aspect of economic decision making nowadays. It is therefore natural to ask how time pressure affects decisions, and how to detect individual heterogeneity in the ability to successfully cope with time pressure. In the context of risky decisions, we ask whether a person’s performance under time pressure can be predicted by measurable behavior and traits, and whether such measurement itself may be affected by selection issues. We find that the ability to cope with time pressure varies significantly across decision makers, leading to selected subgroups that differ in terms of their observed behaviors and personal traits. Moreover, measures of cognitive ability and intellectual efficiency jointly predict individuals’ decision quality and ability to keep their decision strategy under time pressure.

Within-group communication in competitive coordination games has been shown to increase competition between groups and lower efficiency. This study further explores potentially harmful effects of communication, by addressing the questions of (1) asymmetric communication and (2) the endogenous emergence of communication. Our theoretical analysis provides testable hypotheses regarding the effect of communication on competitive behavior and efficiency. We test these predictions using a laboratory experiment. The experiment shows that although asymmetric communication is not as harmful as symmetric communication, it leads to more aggressive competition and lower efficiency relative to the case when neither group can communicate. Moreover, groups vote to endogenously establish communication channels even though they would earn higher payoffs if jointly they chose to restrict within-group communication.