Many countries have implemented a variety of pension reforms in response to the challenges posed by an aging population. These reforms typically involve a trade-off between ‘refinancing’ (i.e., increasing contributions) and ‘retrenchment’ (i.e., reducing benefits). The primary question addressed in this study is whether policymakers in the European Union (EU) possess the necessary capacity to sustain legislated pension reforms, particularly given the growing political influence of the elderly. To examine this issue, we develop a bargaining model designed to optimally allocate the economic burden of aging between successive cohorts of workers and retirees, incorporating retirement incentives. In a scenario where bargaining power remains constant, the optimal allocation rule dictates a fixed-contribution system, effectively shifting the full burden of aging onto the elderly. However, when bargaining power is allowed to fluctuate in response to changes in the relative size of the retiree population (i.e., the dependency rate), the optimal allocation rule involves a compromise between increasing contributions and reducing benefits. In the empirical analysis, we compare these theoretical optimal allocation rules with projections of pension benefit rates and dependency ratios from the 2021 Economic Policy Committee. By calculating the implicit bargaining power required to align projected pension benefits with the optimal sharing rule for each year, we demonstrate a growing divergence between projected pension benefits and the optimal levels in many EU countries, as demographic shifts progress. Furthermore, our findings indicate that for most countries, projected pension benefits are increasingly falling below optimal levels when bargaining power adjusts in accordance with population aging.

Alliance formation typically entails some risk of abandonment, wherein an ally may not honor its obligations in the future. When potential security partners’ preferences are misaligned, this risk looms large, discouraging mutually beneficial investment in an alliance. How can a prospective ally credibly reassure an uncertain patron that their preferences align, to mitigate abandonment risks and elicit a security commitment? We show formally that pre-alliance bargaining with third parties is one way to do so. When the patron holds abandonment concerns, the prospective ally can reassure the patron by making greater concessions to the patron’s existing allies, but more hard-line demands of its rivals. This finding implies that the prospect of an alliance can alternately promote conflict with a prospective patron’s enemies and forestall conflict with its friends. Indeed, we show that incentives for pre-alliance reassurance can result in war, even with perfect asset divisibility, no commitment problems, and complete information among the belligerents. The results are illustrated by China’s intervention in the Korean War and Australia’s post-World War II rapprochement with Japan, which were motivated largely to foster security cooperation with the Soviet Union and the United States, respectively.

We experimentally investigate the effect of time pressure from deadlines in a rich-context bargaining game with an induced reference point at the 2/3-1/3 distribution. Our results show that first proposals, concessions, and settlements are very similar for different time-pressure levels. Nevertheless, time pressure systematically influences the type of agreements reached: the likelihood of bargainers reaching agreements on the equal split is lower under time pressure. Furthermore, disagreements and last-moment-agreements (conditional on reaching an agreement) are more frequently observed under time pressure, though the effect on last-moment agreements disappears when disagreements are included in the analysis. Finally, the effect of time-pressure on the frequency of disagreements is stronger for those pairs with higher tension in first proposals.

Veto power consists of the right of one or more players to unilaterally block decisions but without the ability to unilaterally secure their preferred outcome. Our experiment shows that (i) committees with a veto player take longer to reach decisions (are less efficient) and generate less consensus than without a veto player, (ii) veto power substantially enhances proposer's power, and (iii) non-veto players are substantially more willing to compromise than veto players. We relate our results to the theoretical literature on the impact of veto power as well as to concerns about the impact of veto power in real-life committees.

This study examines fairness perceptions in ultimatum bargaining games with asymmetric payoffs, outside options, and different information states. Fairness perceptions were dependent on treatment conditions. Specifically, when proposers had higher chip values, dollar offers were lower than when responders had higher chip values. When responders had an outside option, offers were higher and were rejected less often than when proposers had an outside option. However, a given offer was rejected more often when responders had an outside option. Therefore, similar to the first mover advantage, the “advantaged” or “entitled” player received a higher monetary payoff than they would otherwise. When there was complete information about payoff amounts (payoff conversion rates and outside options), rejections occurred more often, and given offer amounts were rejected more often than when there was incomplete information. When there was incomplete information, offers were higher in the initial rounds than in the final rounds. These results suggest that proposers made offers strategically, making offers that would not be rejected, rather than out of a concern for fairness.

Learning models predict that the relative speed at which players in a game adjust their behavior has a critical influence on long term behavior. In an ultimatum game, the prediction is that proposers learn not to make small offers faster than responders learn not to reject them. We experimentally test whether relative speed of learning has the predicted effect, by manipulating the amount of experience accumulated by proposers and responders. The experiment allows the predicted learning by responders to be observed, for the first time.

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.

We report on an experiment using video technology to study effects of communication on donations to and discrimination between potential receivers. The experimental design eliminates strategic factors by allowing two receivers to unilaterally communicate with an anonymous dictator before the latter decides on her gifts. Through the use of three communication setups (none, audio, and audio-visual) we analyze purely social effects of communication. A silent video channel leads to discrimination between potential receivers based on impression formation, but does not affect average levels of donations. When the auditory channel is added, average donations increase. The social processes invoked by the visual and audio channels are heterogeneous and communicator-specific but not unsystematic.

We study how culture and social structure influence bargaining behavior across gender, by exploring the negotiation culture in matrilineal and patriarchal societies using data from a laboratory experiment and a natural field experiment. One interesting result is that in both the actual marketplace and in the laboratory bargaining game, women in the matrilineal society earn more than men, at odds with years of evidence observed in the western world. We find that this result is critically driven by which side of the market the person is occupying: female (male) sellers in the matrilineal (patriarchal) society extract more of the bargaining surplus than male (female) sellers. In the buyer role, however, we observe no significant differences across societies.

Bargaining and dilemma games have developed in experimental economics as fairly separate literatures. More than a few analysts are now persuaded that the patterns of behavior in these games are closely related, and considerable effort is being put into a search for models that bridge the gap between the two types of games. I focus on a handful of models that, when taken together, outline the conceptual issues, and provide a sense of the progress that has already been made.

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.

We investigate contract negotiations in the presence of externalities and asymmetric information in a controlled laboratory experiment. In our setup, it is commonly known that it is always ex post efficient for player A to implement a project that has a positive external effect on player B. However, player A has private information about whether or not it is in player A’s self-interest to implement the project even when no agreement with player B is reached. Theoretically, an ex post efficient agreement can always be reached if the externality is large, whereas this is not the case if the externality is small. We vary the size of the externality and the bargaining process. The experimental results are broadly in line with the theoretical predictions. However, even when the externality is large, the players fail to achieve ex post efficiency in a substantial fraction of the observations. This finding holds in ultimatum-game bargaining as well as in unstructured bargaining with free-form communication.

A laboratory study was carried out to analyze the relationship between ambiguity regarding the sharing norms in structured alternating-offer bargaining and gender differences in bargaining. Symmetric environments, where a 50:50 split emerges as the unique sensible norm, showed the lowest ambiguity and gender differences are absent. We increased ambiguity by introducing asymmetries into the bargaining environment by making one bargaining party get a higher share than the other (due to empowerment, entitlement or informational asymmetries), but without imposing new sharing norms. In these situations, men are less likely to reach an agreement, but, when they do, they obtain a larger share of the pie. As a result, men and women show similar overall earnings but earnings are lower when bargaining with men. We find suggestive evidence that gender differences diminish when we reduce ambiguity regarding the sharing norms by providing information about other participants’ agreements in asymmetric environments.