Game theory predicts that players make strategic commitments that may appear counter-intuitive. We conducted an experiment to see if people make a counter-intuitive but strategically optimal decision to avoid information. The experiment is based on a sequential Nash demand game in which a responding player can commit ahead of the game not to see what a proposing player demanded. Our data show that subjects do, but only after substantial time, learn to make the optimal strategic commitment. We find only weak evidence of physical timing effects.

This paper studies how social ties interact with bribery and corruption. In the laboratory, subjects are in triads where two ‘performers’ individually complete an objective real-effort task and an evaluator designates one of them as the winner of a monetary prize. In one treatment dimension, we vary whether performers can bribe the evaluator—where any bribe made is non-refundable, irrespective of the evaluator’s decision. A second treatment dimension varies the induced social ties between the evaluator and the performers. The experimental evidence suggests that both bribes and social ties may corrupt evaluators’ decisions. Bribes decrease the importance of performance in the decision. The effect of social ties is asymmetric. While performers’ bribes vary only little with their ties to the evaluator, evaluators exhibit favoritism based on social ties when bribes are not possible. This ‘social-tie-based’ corruption is, however, replaced by bribe-based corruption when bribes are possible. We argue that these results have concrete consequences for possible anti-corruption policies.

We demonstrate how the standard usage of the random incentive system in ambiguity experiments eliciting certainty and probability equivalents might not be incentive compatible if the decision-maker is ambiguity averse. We propose a slight modification of the procedure in which the randomization takes place before decisions are made and the state is realized, and prove that if subjects evaluate the experimental environment in that way (first-risk, second-uncertainty), incentive compatibility may be restored.

We investigate the effects of order-of-play (simultaneous, unobserved sequential and fully observed sequential play) and form of presentation (extensive vs. normal) in three simple two person games: battle-of-the-sexes with and without outside option and a three strategy game which differentiates between virtual observability (VO) and iterated elimination of dominated strategies as principles of equilibrium selection. VO predicts that knowledge of the order of play alone will affect the distribution of strategies chosen. We contrast this with the predictions of iterated elimination of dominated strategies. We report results from 1800 one-shot games conducted in 6 sessions with 120 subjects and analysed as panel data. The form of presentation strongly affects the distribution of outcomes and strategies. Information about order of play shifts the distribution of strategies away from the distribution in simultaneous play and towards the distribution in fully observed play, especially in the less complicated games presented in normal order. Order-of-play effects are less evident as complexity of the game increases. Extensive form presentation appears to induce sequential thinking even in simultaneously played games.

We describe a common pool resource game in which players choose how much of the stock to extract in a sequential manner. There are two choices and one represents taking a larger proportion of the stock than the other. After a player makes a choice, the remaining stock grows at a constant rate. We consider a game with a finite number of alternating moves. It is shown that changes in the larger proportion of the stock that the players are allowed to take and the growth rate affect equilibrium, but have little effect on behavior in the laboratory. In addition to observing more cooperation than predicted, we observe that parameters that are strategically irrelevant affect behavior. The results of this research might help policy makers in developing adequate policies to prevent overexploitation of some natural renewable resources.

We investigate, in an experimental setting, the effect of private information on the Coase theorem's predictions of efficiency and allocative neutrality. For a two-person bargaining game, we find significantly more inefficiency and allocative bias in the case of private information compared with the case of complete information. We also find substantial bargaining breakdown, which is not predicted by the Coase theorem. For the case of private information, we reject the Coase theorem in favor of the alternative of a generalized version of the Myerson- Satterthwaite theorem, which predicts inefficiency, allocative bias in the direction of the disagreement point, and some bargaining breakdown.

We investigate cooperation using an incremental investment game in which the first-mover has the ability to make small, but increasing incremental investments in their counterpart. Our experiment is designed to test whether establishing trust in small increments is more effective than alternatives, including a one-shot investment game, a decrease only condition where the amount the first-mover sends to the second-mover must be less than the amount previously sent, and an unrestricted condition where the first-mover is not restricted by the amount previously sent. Although results were mixed, broadly, iteration affords greater cooperation than one-shot games and, when given the choice, participants seem to prefer to build trust gradually. Implications for institutional design are discussed.

Preferences for charitable giving in auctions can be modeled by assuming that bidders receive additional utility proportional to the revenue raised by an auctioneer. The theory of bidding in the presence of such preferences results in a very counterintuitive prediction which is that, in many cases, bidders having preferences for charitable giving does not lead to a substantial revenue advantage for an auctioneer. We test this theory and this prediction with a series of experiments. In one experiment we induce charitable preferences exactly as specified in the model to see if bidders respond to them as predicted. We find that they do. We then conduct a second experiment in which the revenue from the auctions is donated to actual charities to verify the robustness of the prediction when charitable preferences are generated by a more natural source and find again that the theoretical prediction holds: even strong charitable preferences do not result in substantial revenue increases to the auctioneer.

We present a large scale study where a nationally representative sample of 1000 participants were asked to make real purchases within an online supermarket platform. The study captured the effect of price changes, and of the signposting of such changes, for breakfast cereals and soft drinks. We find that such taxes are an effective means of altering food purchasing, with a 20% rate being sufficient to make a significant impact if (and only if) the tax is signposted. Signposting represents a complementary “nudge” policy that could enhance the impact of the tax, though its effectiveness depends on the product category.

Ostracism is practiced by virtually all societies around the world as a means of enforcing cooperation. In this paper, we use a public goods experiment to study whether groups choose to implement an institution that allows for the exclusion of members. We distinguish between a costless exclusion institution and a costly exclusion institution that, if chosen, reduces the endowment of all players. We also provide a comparison with an exclusion institution that is exogenously imposed upon groups. A significant share of the experimental groups choose the exclusion institution, even when it comes at a cost, and the support for the institution increases over time. Average contributions to the public good are significantly higher when the exclusion option is available, not only because low contributors are excluded but also because high contributors sustain a higher cooperation level under the exclusion institution. Subjects who vote in favor of the exclusion institution contribute more than those who vote against it, but only when the institution is implemented. These results are largely inconsistent with standard economic theory but can be better explained by assuming heterogeneous groups in which some players have selfish and others have social preferences.

We explore the efficiency and distributive implications of a multilateral bargaining model with endogenous production of the surplus under two different timings: ex ante and ex post bargaining. Both timings are commonly observed in business partnerships and alliance formations. The theoretical predictions confirm an intuitive economic tenet: in ex post bargaining, effort is considered sunk and opportunistic bargaining behavior will dissuade players from producing. On the other hand, ex ante bargaining entails an allocation of ownership shares that induces at least certain members to invest in the common fund because their return is guaranteed. Experiments show opposite results: ex post bargaining yields almost fully efficient outcomes while the reverse timing entails near zero efficiency. The psychological theory of inequity is useful in reconciling these divergent results.

The underpricing of initial public offerings (IPO) is a well-documented fact of empirical equity market research. Theories explain this underpricing with market imperfections. We study three empirically relevant IPO mechanisms under almost perfect market conditions in the laboratory: a stylized book building approach, a closed book auction, and an open book auction. We report underpricing in each of these IPO mechanisms. Uncertainty about the aftermarket behavior may partly explain IPO excess returns but underpricing persists even in the repeated setting where uncertainty is negligible and despite the equilibrium adjustment dynamics, that we observe in the data. The data reveal a market-wide impact of investors’ reluctance to sell in the aftermarket at a price below the offering price. We conclude that a behavioural bias similar to the disposition effect fosters IPO underpricing in our setting.

We provide a simplified test to determine if choice data from a two-commodity consumption set satisfies the Generalized Axiom of Revealed Preference (GARP), and thus the preference or utility maximization hypothesis. We construct an algorithm for this test and illustrate its application on experimental choice data.

While both simultaneous and sequential contests are mechanisms used in practice such as crowdsourcing, job interviews and sports contests, few studies have directly compared their performance. By modeling contests as incomplete information all-pay auctions with linear costs, we analytically and experimentally show that the expected maximum effort is higher in simultaneous contests, in which contestants choose their effort levels independently and simultaneously, than in sequential contests, in which late entrants make their effort choices after observing all prior participants’ choices. Our experimental results also show that efficiency is higher in simultaneous contests than in sequential ones. Sequential contests’ efficiency drops significantly as the number of contestants increases. We also discover that when participants’ ability follows a power distribution, high ability players facing multiple opponents in simultaneous contests tend to under-exert effort, compared to theoretical predictions. We explain this observation using a simple model of overconfidence.

We experimentally subliminally prime subjects prior to charity donation decisions by showing words that have connotations of pro-social values for a very brief time (17 ms). Our main finding is that, compared to a baseline condition, the pro-social prime increases donations by approximately 10–17 % among subjects with strong pro-social preferences (universalism values). We find a similar effect when interacting the prime with the Big 5 personality characteristic of agreeableness. We furthermore introduce a novel method for testing for priming, “subliminity”. This method reveals that some subjects are capable of recognizing prime words, and the overall results are weaker when we control for this capacity.

We explore if fairness and inequality motivations affect cooperation in indefinitely repeated games. Each round, we randomly divided experimental participants into donor–recipient pairs. Donors could make a gift to recipients, and ex-ante earnings are highest when all donors give. Roles were randomly reassigned every period, which induced inequality in ex-post earnings. Theoretically, income-maximizing players do not have to condition on this inequality because it is payoff-irrelevant. Empirically, payoff-irrelevant inequality affected participants’ ability to coordinate on efficient play: donors conditioned gifts on their own past roles and, with inequalities made visible, discriminated against those who were better off.

This paper provides experimental evidence of the role of higher order risk attitudes—especially prudence—in prevention behavior. Prudence, under an expected utility framework, increases (decreases) self-protection effort compared to the risk neutral level when the risk of losing part of an income exists in a future (the same) period. Motivated by these predictions that give the exact test on prudence, an experiment was designed where subjects go through higher order risk attitude elicitation and make a self-protection decision. In contrast to the expected utility theory, the observed efforts are less than the risk neutral level, regardless of the timing of loss. This violation of expected utility predictions can be explained by probability weighting.

This paper presents and tests a simple model of competitive and unilateral market power regimes that yields countercyclical markups. Following a decrease in demand in the short run, capacity-constrained firms may have a strong incentive not to lower their prices to the new competitive price. Demand shocks may introduce market power into a previously competitive market. Experimental posted offer markets support this conjecture with complete information on the market structure. With only private information, there appears to be a hysteresis effect concerning supracompetitive prices, i.e., markets with a history of supracompetitive pricing continue to generate supracompetitive prices following demand shocks. However, competitive markets also remain competitive following demand shocks when firms only have private information on costs and capacities.

We investigate the implications of Salience Theory for the classical preference reversal phenomenon, where monetary valuations contradict risky choices. It has been stated that one factor behind reversals is that monetary valuations of lotteries are inflated when elicited in isolation, and that they should be reduced if an alternative lottery is present and draws attention. We conducted two preregistered experiments, an online choice study ($N=256$) and an eye-tracking study ($N=64$), in which we investigated salience and attention in preference reversals, manipulating salience through the presence or absence of an alternative lottery during evaluations. We find that the alternative lottery draws attention, and that fixations on that lottery influence the evaluation of the target lottery as predicted by Salience Theory. The effect, however, is of a modest magnitude and fails to translate into an effect on preference reversal rates in either experiment. We also use transitions (eye movements) across outcomes of different lotteries to study attention on the states of the world underlying Salience Theory, but we find no evidence that larger salience results in more transitions.

Our paper reconsiders the triadic design proposed by Cox (Games and Economic Behavior 46:260–281, 2004) to identify trust and reciprocity in investment games. Specifically, we extend the design in two directions. First, we collect information on investors’ choices by using both the direct-response (as does Cox) and strategy methods. Using the latter, we are able to condition reciprocity on initial inequality, which is endogenous when investigating reciprocity. We demonstrate that the triadic design provides evidence for reciprocity once that initial inequality is considered. Second, we elicit expectations and test their coherence with the triadic outcomes. By examining the relationship between trust actions and expected gains, we analyze whether investors’ expectations are consistent with their behavior. Finally, we test for the existence of an emotional bias, i.e., whether expectation mismatches induce trustees to change actual choices from the planned ones.