Both the law and culture distinguish between acts of commission that overturn the status quo and acts of omission that uphold it. This distinction is of central importance when it comes to reciprocal actions. A stylized fact of everyday life is that acts of commission elicit stronger reciprocal responses than do acts of omission. We report experiments that directly test whether this stylized fact characterizes behavior in controlled experiments. We compare reciprocal responses to both types of acts in experiments using binary, extensive form games. Across three experiments, we examine the robustness of our results to different ways in which the status quo can be induced in experiments. The data show a clear difference between effects of acts of commission and omission by first movers on reciprocal responses by second movers.

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.

This paper compares behavior under four different implementations of infinitely repeated games in the laboratory: the standard random termination method [proposed by Roth and Murnighan (J Math Psychol 17:189–198, 1978)] and three other methods that de-couple the expected number of rounds and the discount factor. Two of these methods involve a fixed number of repetitions with payoff discounting, followed by random termination [proposed by Sabater-Grande and Georgantzis (J Econ Behav Organ 48:37–50, 2002)] or followed by a coordination game [proposed in (Andersson and Wengström in J Econ Behav Organ 81:207–219, 2012; Cooper and Kuhn in Am Econ J Microecon 6:247–278, 2014a)]. We also propose a new method—block random termination—in which subjects receive feedback about termination in blocks of rounds. We find that behavior is consistent with the presence of dynamic incentives only with methods using random termination, with the standard method generating the highest level of cooperation. Subject behavior in the other two methods display two features: a higher level of stability in cooperation rates and less dependence on past experience. Estimates of the strategies used by subjects reveal that across implementations, even when the discount rate is the same, if interactions are expected to be longer defection increases and the use of the Grim strategy decreases.

We use data from experiments on finitely repeated dilemma games with fixed matching to investigate the effect of different types of information on cooperation. The data come from 71 studies using the voluntary contributions paradigm, covering 122 data points, and from 18 studies on decision-making in oligopoly, covering another 50 data points. We find similar effects in the two sets of experimental games. We find that transparency about what everyone in a group earns reduces contributions to the public good, as well as the degree of collusion in oligopoly markets. In contrast, transparency about choices tends to lead to an increase in contributions and collusion, although the size of this effect varies somewhat between the two settings. Our results are potentially useful for policy making, because they provide guidance on the type of information to target in order to stimulate or limit cooperation.

We measure participants’ willingness to pay for transparently useless authority—the right to make a completely uninformed task decision. We further elicit participants’ beliefs about receiving their preferred outcome if they make the decision themselves, and if another participant makes the decision for them. We find that participants pay more to make the decision themselves if they also believe that they can thus increase the probability of getting their preferred outcome. Illusion of control therefore exists in a controlled laboratory environment with monetary incentives and is connected to peoples’ pursuit of authority.

Bidding one’s value in a second-price, private-value auction is a weakly dominant solution (Vickrey in J Finance 16(1):8–37, 1961), but repeated experimental studies find more overbidding than underbidding. We propose a model of optimistically irrational bidders who understand that there are possible gains and losses associated with higher bids but who may overestimate the additional probability of winning and/or underestimate the potential losses when bidding above value. These bidders may fail to discover the dominant strategy—despite the fact that the dominant strategy only requires rationality from bidders—but respond in a common sense way to out-of-equilibrium outcomes. By varying the monetary consequences of losing money in experimental auctions we observe more overbidding when the cost to losing money is low, and less overbidding when the cost is high. Our findings lend themselves to models in which less than fully rational bidders respond systematically to out-of-equilibrium incentives, and we find that our model better fits the effects of our manipulations than most of the existing models we consider.

Non-monetary rewards are frequently used to promote pro-social behaviors, and these behaviors often result in approval from one’s peers. Nevertheless, we know little about how peer-approval, and particularly competition for peer-approval, influences people’s decisions to cooperate. This paper provides experimental evidence suggesting that people in peer-approval competitions value social approval more when it leads to unique and durable rewards. Our evidence suggests that such rewards act as a signaling mechanism, thereby contributing to the value of approval. We show that this signaling mechanism generates cooperation at least as effectively as cash rewards. Our findings point to the potential value of developing new mechanisms that rely on small non-monetary rewards to promote generosity in groups.

We provide experimental evidence on the ability to detect deceit in a buyer–seller game with asymmetric information. Sellers have private information about the value of a good and sometimes have incentives to mislead buyers. We examine if buyers can spot deception in face-to-face encounters. We vary whether buyers can interrogate the seller and the contextual richness. The buyers’ prediction accuracy is above chance, and is substantial for confident buyers. There is no evidence that the option to interrogate is important and only weak support that contextual richness matters. These results show that the information asymmetry is partly eliminated by people’s ability to spot deception.

We develop a model that relates self-control to cooperation patterns in social dilemmas, and we test the model in a laboratory public goods experiment. As predicted, we find a robust association between stronger self-control and higher levels of cooperation, and the association is at its strongest when the decision maker’s risk aversion is low and the cooperation levels of others high. We interpret the pattern as evidence for the notion that individuals may experience an impulse to act in self-interest—and that cooperative behavior benefits from self-control. Free-riders differ from other contributor types only in their tendency not to have identified a self-control conflict in the first place.

Legal disputes are often negotiated under the backdrop of an adjudicated award. While settlements are common, they are not universal. In this paper, we empirically explore how uncertainty in adjudicated awards impacts settlement negotiations. To do so, we develop an experimental design to test how increases in variance and positive skewness of the award distribution impact negotiations and settlement rates. We find increases in variance decrease settlement rates, while increases in skewness generally increases settlement rates. We also gather individual measures of risk aversion and prudence, and incorporate these measures into the analysis to test for heterogeneous treatment effects. Overall, our results suggest that highly variable adjudicated awards can contribute to the excess use of inefficient litigation, while more positively skewed awards can reduce the use of inefficient litigation.

Using an appropriation game setting, we examine individual responses to changes in a groups’ vulnerability to a probabilistic loss (L) of a public good. The probabilistic loss parameter entails losing 10, 50 or 90% of the value of the public good that is maintained through cooperation, where the likelihood of the loss decreases in total group cooperation. By design, the expected marginal net benefits to an individual and the expected harm to others depends endogenously on the individuals’ expectations of group cooperation and exogenously on the magnitude of the loss parameter. We find that individual cooperation is greater when forecasts of total group cooperation are greater and where the magnitude of the probabilistic loss is larger. There is, however, an interesting asymmetry in responses by two subgroups. Subjects who are pessimistic regarding total group cooperation decrease cooperation the higher the magnitude of the probabilistic loss and their decisions are tied systematically to changes in their expectations of other’s cooperation. On the other hand, subjects who are optimistic regarding total group cooperation are found to be more cooperative, but their decisions are not systematically tied to changes in expectations of others’ cooperation.

We use a combination of theory and experiment to study the incentives for firms to share knowledge when they engage in research and development (R&D) in an uncertain environment. We consider both symmetric and asymmetric starting points with regards to the amount of initial knowledge firms have before conducting R&D and look at how differences in starting positions affect the willingness of firms to share knowledge. We investigate when and if firms find R&D cooperation beneficial and how investment in R&D is affected by the outcome of the sharing decisions. The experimental evidence shows that overall subjects tend to behave consistently with theoretical predictions for the sharing of knowledge, although leaders who are not compensated by a side payment from laggards are more willing to share than predicted by the theory, and leaders who are compensated are less willing. The data on investment suggests less investment with sharing than without, consistent with theory. Compared to exact numerical predictions, there is overinvestment or underinvestment except for symmetric firms under no sharing. All cases of overinvestment and underinvestment, regardless of sharing or not and regardless of starting positions, are well explained by smoothed-out best (quantal) responses.

We experimentally study optional costly communication in Stag-Hunt games. Prior research demonstrates that efficient coordination is difficult without a communication option but obtains regularly with mandatory costless pre-play messages. We find that even small communication costs dramatically reduce message use when communication is optional, but efficient coordination can occur with similar frequency as under costless communication. These findings can be accounted for by formalizations of forward induction that take Nash equilibrium as a reference point (such as Kohlberg and Mertens in Econometrica 54: 1003–1037, 1986; Govindan and Wilson in Econometrica 77: 1–28, 2009), while formalizations that only appeal to (higher-order) knowledge of rationality remain silent in this environment.

The fraction of a user population willing to tolerate nuisances of size x is summarized in the survivor curve S(x); its shape is crucial in economic decisions such as pricing and advertising. We report a laboratory experiment that, for the first time, estimates the shape of survivor curves in several different settings. Laboratory subjects engage in a series of six desirable activities, e.g., playing a video game, viewing a chosen video clip, or earning money by answering questions. For each activity and each subject we introduce a chosen level $x\in [x_{min},x_{max}]$ of a particular nuisance, and the subject chooses whether to tolerate the nuisance or to switch to a bland activity for the remaining time. New non-parametric techniques provide bounds on the empirical survivor curves for each activity. Parametric fits of the classic Weibull distribution provide estimates of the survivor curves’ shapes. The fitted shape parameter depends on the activity and nuisance, but overall the estimated survivor curves tend to be log-convex. An implication, given the model of Aperjis and Huberman (SSRN, doi: 10.2139/ssrn.1672820, 2011), is that introducing nuisances all at once will generally be more profitable than introducing them gradually.

We experimentally study the effects of allotment—the division of an item into homogeneous units—in independent private value auctions. We compare a bundling first-price auction with two equivalent treatments where allotment is implemented: a two-unit discriminatory auction and two simultaneous single-unit first-price auctions. We find that allotment in the form of a discriminatory auction generates a loss of efficiency with respect to bundling. In the allotment treatments, we observe large and persistent bid spread, and the discriminatory auction is less efficient than simultaneous auctions. We provide a unified interpretation of our results that is based on both a non-equilibrium response to the coordination problem characterizing the simultaneous auction format and a general class of behavioral preferences that includes risk aversion, joy of winning and loser’s regret as specific cases.

We experimentally study ways in which social preferences affect individual and group performance under indefinitely repeated relative incentives. We also identify the mediating role that communication and leadership play in generating these effects. We find other-regarding individuals tend to depress efforts by 15% on average. However, selfish individuals are nearly three times more likely to lead players to coordinate on minimal efforts when communication is possible. Hence, the other-regarding composition of a group has complex consequences for organizational performance.

This study develops a theoretical, and experimental analysis addressing the issue of premium variations on the demand for insurance. Accounting for risk attitudes, our contribution disentangles the decision to buy insurance from the conditional demand (the non-null demand for insurance). Partially validating our theoretical predictions, our experimental results show that, when it has an effect, a non-massive increase in the premium (either in the unit price or the fixed cost) exclusively results in an exit from the insurance market (the risk lovers first, then the risk averters). Moreover, our study highlights a key feature of risk-seeking agents' behavior; they exhibit behavior consistent with gambling and opportunism rather than a lack of interest in insurance.

We design a laboratory experiment to examine predictions of trustworthiness in a novel three-person trust game. We investigate whether and why observers of the game can predict the trustworthiness of hand-written communications. Observers report their perception of the trustworthiness of messages, and make predictions about the senders’ behavior. Using observers’ decisions, we are able to classify messages as “promises” or “empty talk.” Drawing from substantial previous research, we hypothesize that certain factors influence whether a sender is likely to honor a message and/or whether an observer perceives the message as likely to behonored: the mention of money; the use of encompassing words; and message length. We find that observers have more trust in longer messages and “promises”; promises that mention money are significantly more likely to be broken; and observers trust equally in promises that do and do not mention money. Overall, observers perform slightly better than chance at predicting whether a message will be honored. We attribute this result to observers’ ability to distinguish promises from empty talk, and to trust promises more than empty talk. However, within each of these two categories, observers are unable to discern between messages that senders will honor from those that they will not.

Are people willing to sacrifice resources to save one’s and others’ face? In a laboratory experiment, we study whether individuals forego resources to avoid the public exposure of the least performer in their group. We show that a majority of individuals are willing to pay to preserve not only their self- but also other group members’ image, even when group identity is minimal. When group identity is made more salient, individuals help regardless of whether the least performer is an in-group or an out-group. In contrast, people are less likely to sacrifice for individual strangers, showing a major role for group identity and reputation concerns within groups relative to an interpretation in terms of moral norms.

This paper investigates whether and to what extent group identity plays a role in peer effects on risk behaviour. We run a laboratory experiment in which different levels of group identity are induced through different matching protocols (random or based on individual painting preferences) and the possibility to interact with group members via an online chat in a group task. Risk behaviour is measured by using the Bomb Risk Elicitation Task and peer influence is introduced by giving subjects feedback regarding group members’ previous decisions. We find that subjects are affected by their peers when taking decisions and that group identity influences the magnitude of peer effects: painting preferences matching significantly reduces the heterogeneity in risk behaviour compared with random matching. On the other hand, introducing a group task has no significant effect on behaviour, possibly because interaction does not always contribute to enhancing group identity. Finally, relative riskiness within the group matters and individuals whose peers are riskier than they are take on average riskier decisions, even when controlling for regression to the mean.