John Stuart Mill claimed that “men do not desire merely to be rich, but richer than other men.” Are people made happy by being richer than others? Or are people made happy by favorable comparisons to others more generally, and being richer is merely a proxy for this ineffable relativity? We conduct an online experiment absent choice in which we measure subjective well-being (SWB) before and after an exogenous shock that reveals to subjects how many experimental points they and another subject receive, and whether or not points are worth money. We find that subjects are made significantly happier when they receive monetized rather than non-monetized points, suggesting money is valued more than the points it represents. In contrast, subjects are made equally unhappy when they receive fewer monetized points as when they receive fewer non-monetized points than others, suggesting relative money is not valued more than the relative points it represents. We find no evidence that subjects are made happier by being “richer” than others (i.e., by receiving more points—either monetized or non-monetized—than others). Subgroup analyses reveal women are made unhappier (than men) by being “richer” and “poorer” than others, and conservatives are made unhappier (than progressives) by being “poorer” than others. Our experimental-SWB approach is easy to administer and may complement choice-based tasks in future experiments to better estimate preference parameters.

In a Diamond–Dybvig type model of financial intermediation, we allow depositors to announce at a positive cost to subsequent depositors that they keep their funds deposited in the bank. Theoretically, the mere availability of public announcements (and not its use) ensures that no bank run is the unique equilibrium outcome. Multiple equilibria—including bank run—exist without such public announcements. We test the theoretical results in the lab and find a widespread use of announcements, which we interpret as an attempt to coordinate on the no bank run outcome. Withdrawal rates in general are lower in information sets that contain announcements.

Rationality is a fundamental pillar of Economics. It is however unclear if this assumption holds when decisions are made under stress. To answer this question, we design two laboratory experiments where we exogenously induce physiological stress in participants and test the consistency of their choices with economic rationality. In both experiments we induce stress with the Cold Pressor test and measure economic rationality by the consistency of participants’ choices with the Generalized Axiom of Revealed Preference (GARP). In the first experiment, participants delay the decision-making task for 20 min until the cortisol level peaks. We find significant differences in cortisol levels between the stressed group and the placebo group which, however, do not affect the consistency of choices with GARP. In a second experiment, we study the immediate effect of the stressor on rationality. Overall, results from the second experiment confirm that rationality is not impaired by the stressor. If anything, we observe that compared to the placebo group, participants are more consistent with rationality immediately after the stressor. Our findings provide strong empirical support for the robustness of the economic rationality assumption under physiological stress.

Social media permeates many aspects of our lives, including how we connect with others, where we get our news and how we spend our time. Yet, we know little about the economic effects for users. In 2017, we ran a large field experiment with over 1765 individuals to document the value of Facebook to users and its causal effect on news, well-being and daily activities. Participants reveal how much they value one week of Facebook usage and are then randomly assigned to a validated Facebook restriction or normal use. One week of Facebook is worth $67. Those who are off Facebook for one week reduce news consumption, are less likely to recognize politically-skewed news stories, report being less depressed and engage in healthier activities. These results are strongest for men. Our results further suggest that, after the restriction, Facebook’s value increases, consistent with information loss or that using Facebook may be addictive.

Buying lottery tickets is not a rational investment from a financial point of view. Yet, the majority of people participate at least once a year in a lottery. We conducted a field experiment to increase understanding of lottery participation. Using representative data for the Netherlands, we find that lottery participation increased the happiness of participants before the draw. Winning a small prize had no effect on happiness. Our results indicate that people may not only care about the outcomes of the lottery, but also enjoy the game. Accordingly, we conclude that lottery participation has a utility value in itself and part of the utility of a lottery ticket is consumed before the draw.

We present evidence of a direct social context effect on decision-making under uncertainty: the gender composition of those in the room when making individual risky decisions significantly alters choices even when the actions or presence of others are not payoff relevant. In our environment, decision makers do not know the choices made by others, nor can they be inferred from the experiment. We find that women become more risk taking as the proportion of men in the room increases, but the behavior of men is unaffected by who is present. We discuss some potential mechanisms for this result and conjecture it is driven by women being aware of the social context and imitating the expected behavior of others. Our results imply that the environment in which individual decisions are made can change expressed preferences and that aggregate behavior may be context dependent.

We report on an experimental investigation of the emergence of Spontaneous Order, the idea that societies can co-ordinate, without government intervention, on a form of society that is good for its citizens, as described by Adam Smith. Our experimental design is based on a production game with a convex input provision possibility frontier, where subjects have to choose a point on this frontier. We start with a simple society consisting of just two people, two inputs, one final good and in which the production process exhibits returns to specialisation. We then study more complex societies by increasing the size of the society (groups of 6 and 9 subjects) and the number of inputs (6 and 9 inputs respectively), as well as the combinations of inputs that each subject can provide. This form of production can be characterised as a cooperative game, where the Nash equilibrium predicts that the optimal outcome is achieved when each member of this society specialises in the provision of a single input. Based on this framework, we investigate whether Spontaneous Order can emerge, without it being imposed by the government. We find strong evidence in favour of the emergence of Spontaneous Order, with communication being an important factor. Using text classification algorithms (Multinomial Naive Bayes) we quantitatively analyse the available chat data and we provide insight into the kind of communication that fosters specialisation in the absence of external involvement. We note that, while communication has been shown to foster coordination in other contexts (for example, in public goods games, market entry games and competitive coordination games) this contribution is in the context of a production game where specialisation is crucial.