The gift‐exchange game has established that, in the laboratory, higher wages offered by an employer lead to considerably more costly effort provision. However, it is unclear whether this behavior reflects reciprocity or other forms of social preferences. This article tests whether attribution of volition in choosing a wage has a significant effect on subsequent costly effort provision. Treatments varied whether wages were chosen by the employer or by an external process. We see that both distributional concerns and reciprocity play a major role. The data are examined in the light of recent utility models.

We study worker behavior in an efficiency‐wage environment in which coworkers’ wages can influence a worker’s effort. Theoretically, we show that an increase in workers’ responsiveness to coworkers’ wages should lead profit‐maximizing firms to compress wages. Our laboratory experiments, by contrast, show that while workers’ effort choices are highly sensitive to their own wages, effort is not affected by coworkers’ wages. This casts doubt on the notion that workers’ concerns with equity might explain pay policies such as wage compression or wage secrecy.

We review the vast literature on social preferences by assessing what is known about their fundamental properties, their distribution in the broader population, and their consequences for important economic and political behaviors. We provide, in particular, an overview of the empirical characteristics of distributional preferences and how they are affected by merit, luck, and concerns for equality of opportunity. In addition, we discuss the evidence for reciprocity and guilt aversion and assess the empirical relevance of self-image and social image concerns in prosocial behaviors. The overall evidence indicates that a large majority of individuals have some sort of social preferences, while purely self-interested subjects are a minority. We also document converging insights from the lab and the field on the impact of wage inequality on work morale, employees’ resistance to wage cuts, and the role of social preferences for cooperation and collective action, distributive politics, and individuals’ selection into different occupations.

Can incentives be effective in encouraging the development of good habits? We investigate the post-intervention effects of paying people to attend a gym a number of times during one month. In two studies we find marked attendance increases after the intervention relative to attendance changes for the respective control groups. This is entirely driven by people who did not previously attend the gym on a regular basis. In our second study, we find improvements on health indicators such as weight, waist size, and pulse rate, suggesting the intervention led to a net increase in total physical activity rather than to a substitution away from nonincentivized ones. We argue that there is scope for financial intervention in habit formation, particularly in the area of health.

We examine experimentally the impact of communication on trust and cooperation. Our design admits observation of promises, lies, and beliefs. The evidence is consistent with people striving to live up to others' expectations so as to avoid guilt, as can be modeled using psychological game theory. When players exhibit such guilt aversion, communication may influence motivation and behavior by influencing beliefs about beliefs. Promises may enhance trustworthy behavior, which is what we observe. We argue that guilt aversion may be relevant for understanding strategic interaction in a variety of settings, and that it may shed light on the role of language, discussions, agreements, and social norms in these contexts.

We show experimentally that whether and how communication achieves beneficial social outcomes in a hidden-information context depends crucially on whether low-talent agents can participate in a Pareto-improving outcome. Communication is effective (and pat terns of lies and truth quite systematic) when this is feasible, but otherwise completely ineffective. We examine the data in light of two potentially relevant behavioral models: cost-of-lying and guilt-from-blame.

When Optimal Choices Feel Wrong: A Laboratory Study of Bayesian Updating, Complexity, and Affect by Gary Charness and Dan Levin. Published in volume 95, issue 4, pages 1300-1309 of American Economic Review, September 2005

Modigliani and Miller show that the total market value of a firm is unaffected by a repackaging of asset return streams to equity and debt if pricing is arbitrage‐free. We investigate this invariance theorem in experimental asset markets, finding value‐invariance for assets of identical risks when returns are perfectly correlated. However, exploiting price discrepancies has risk when returns have the same expected value but are uncorrelated, in which case the law of one price is violated. Discrepancies shrink in consecutive markets, but persist even with experienced traders. In markets where overall trader acuity is high, assets trade closer to parity.

There is economic pressure to postpone the retirement age, but employers are still reluctant to employ older workers. We investigate the comparative behavior of juniors and seniors in experiments conducted both onsite with the employees of two large firms and in a conventional laboratory environment with students and retirees. We show that seniors are no more risk averse than juniors and are typically more cooperative; both juniors and working seniors respond strongly to competition. The implication is that it may be beneficial to define additional incentives near the end of the career to motivate and retain older workers.

In labor markets, the ratchet effect refers to a situation where workers subject to performance pay choose to restrict their output, because they rationally anticipate that firms will respond to higher output levels by raising output requirements or by cutting pay. We model this effect as a multiperiod principal-agent problem with hidden information and study its robustness to labor market competition both theoretically and experimentally. Consistent with our theoretical model, we observe substantial ratchet effects in the absence of competition, which are nearly eliminated when competition is introduced; this is true regardless of whether market conditions favor firms or workers.