In three between-subject experiments, involving a total of 3180 participants, the majority of respondents indicated that during a weather emergency they would continue to use high bandwidth functions after receiving a text message requesting only emergency use. Projected excess demand for bandwidth could bring down the cellular communication network in the affected area. Messages incorporating an appeal to altruism, the incentive of a reduced phone bill, and the disincentive of an imminent collapse of the network for 24 hours all had no effect on intentions to use high bandwidth functions. Younger respondents and male respondents were less compliant than older respondents and female respondents. Their responses imply that an increasing number of individuals view even a brief separation from their cell phone as an existential threat that overrides other concerns including empathy for people in life-threatening circumstances.

Culture consists of practices – behaviour patterns – shared by members of a group. Some attempts to demonstrate evolution of cultural practices in the laboratory have shown evolution of material products, such as paper aeroplanes. Some attempts have shown evolution of actual group behaviour. The present experiments demonstrated evolution of group coordination across generations in punishing defection in a public-goods game. Cost of punishing defection varied across replicates that consisted of series of groups (generations) of 10 undergraduates each. Each generation played the game anonymously for 10 rounds and could write messages to the other participants and punish defection every round. The effectiveness of punishment depended on the number of participants choosing to punish. In Experiment 1, cultural transmission from generation to generation consisted of written advice from one generation read aloud to the next generation. In Experiment 2, transmission from generation to generation consisted of having some participants return from the previous group. The cost of punishing varied across replicates: zero, one, two or five cents. In both experiments, the evolution of altruistic punishing was strongly dependent on the cost of punishing. The results add to plausibility of studying evolution of complex behaviour patterns like cooperation in the laboratory.

Since the early 1950s, national statisticians have regarded unpaid work as non-economic, excluding it from GDP. Feminist scholars argue this exclusion reflects a gender-biased view of progress that renders women’s non-market productivity invisible. As what gets measured drives policy priorities and resource allocation, breastfeeding highlights the need to account for women’s unpaid care work in economic statistics. This paper advances the Beyond GDP agenda by demonstrating how market-derived prices can improve the measurement and recognition of women’s lactation labour. We first trace the historical displacement of breastfeeding by commercial formula and identify key economic drivers. Next, we review critiques of GDP and debates over including non-market household services in the UN’s System of National Accounts. We then present novel estimates of breast milk’s economic value in selected countries. Our analysis shows that existing market prices can robustly proxy for breastfeeding work, correcting GDP’s gender bias and realigning policy priorities. Including human milk production in core economic indicators not only reflects its true contribution but also promotes women’s and children’s rights and supports sustainable development through comprehensive true-cost accounting.

Are people more inclined to help strangers when they’ve experienced similar hardships? People who have experienced displacement could be tremendous allies to the newly displaced, but they are relatively understudied. This study explores how people who have experienced wartime displacement respond to refugees fleeing new violence. I prime Serbs who experienced wartime displacement with either (1) their experience of displacement or (2) their ethnic identity. I then measure their altruism toward Syrian refugees traveling the Balkan route. Compared to participants who were reminded of their ethnic identity, participants who were reminded of their displacement were no more generous toward displaced Syrians. In fact, participants who experienced displacement, as well as wartime violence, were more generous toward the refugees when they were reminded of their ethnic identity. These results suggest that shared hardship alone may not necessarily enhance refugee inclusion. The results further suggest that interventions may benefit from calling out the differences between hosts and refugees—in this case, on the dimension of ethnicity. These findings caution humanitarians to construct their interventions with care.

Several papers have documented that when subjects play with standard laboratory “endowments” they make less self-interested choices than when they use money they have either earned through a laboratory task or brought from outside the lab. In the context of a charitable giving experiment we decompose this into two common artifacts of the laboratory: the intangibility of money (or experimental currency units) promised on a computer screen relative to cash in hand, and the distinct treatment of random “windfall” gains relative to earned money. While both effects are found to be significant in non-parametric tests, the former effect, which has been neglected in previous studies, has a stronger impact on total donations, while the latter effect has a greater impact on the probability of donating. These results have clear implications for experimental design, and also suggest that the availability of more abstract payment methods may increase other-regarding behavior in the field.

Charitable donations provide positive externalities and can potentially be increased with an understanding of donor preferences. We obtain a uniquely comprehensive characterization of donation motives using an experiment that varies treatments between and within subjects. Donations are increasing in peers’ donations and past subjects’ donations. These and other results suggest a model of heterogeneous beliefs about the social norm for giving. Estimation of such a model reveals substantial heterogeneity in subjects’ beliefs about and adherence to the norm. A simple fundraising strategy increases donations by an estimated 30% by exploiting previously unstudied correlations between dimensions of donor preferences.

Experimental dictator games have been used to explore unselfish behaviour. Evidence is presented here, however, that subjects’ generosity can be reversed by allowing them to take a partner's money. Dictator game giving therefore does not reveal concern for consequences to others existing independently of the environment, as posited in rational choice theory. It may instead be an artefact of experimentation. Alternatively, evaluations of options depend on the composition of the choice set. Implications of these possibilities are explored for experimental methodology and charitable donations respectively. The data favour the artefact interpretation, suggesting that demand characteristics of experimental protocols merit investigation, and that economic analysis should not exclude context-specific social norms.

Temporary changes in biological state, such as hunger, can impact decision making differently for men and women. Food scarcity is correlated with a host of negative economic outcomes. Two explanations for this correlation are that hunger affects economic preferences directly or that hunger creates a mindset that focuses on scarcity management to the detriment of other decisions. To test these predictions, we conduct a lab-in-the-field experiment in a health screening clinic in Shanghai, recruiting participants who finish their annual physical exam either before or after they have eaten breakfast. We compare the hungry and sated groups on their risk, time and generosity preferences as well as their cognitive performance. Our results show that men and women respond to hunger in opposite directions, thus hunger reduces the gender gap in decision quality, risk aversion and cognitive performance, but creates one in generosity. Finally, we examine several biomarkers and find that higher blood lipid levels are correlated with greater choice inconsistency, risk aversion and generosity. We contribute to emerging insights on the biological foundations for economic preferences and outcomes.

We conduct a representative dictator game in which students and random members of the community choose both what charity to support and how much to donate to the charity. We find systematic differences between the choices of students and community members. Community members are much more likely to write in their own charity, community members donate significantly more ($17), on average, and community members are much more likely (32%) to donate the entire $100 endowment. Based on this evidence, it does not appear that student behavior is very representative in the context of the charitable donations and the dictator game.

There is substantial evidence that women tend to support different policies and political candidates than men. Many studies also document gender differences in a variety of important preference dimensions, such as risk-taking, competition and pro-sociality. However, the degree to which differential voting by men and women is related to these gaps in more basic preferences requires an improved understanding. We conduct an experiment in which individuals in small laboratory “societies” repeatedly vote for redistribution policies and engage in production. We find that women vote for more egalitarian redistribution and that this difference persists with experience and in environments with varying degrees of risk. This gender voting gap is accounted for partly by both gender gaps in preferences and by expectations regarding economic circumstances. However, including both these controls in a regression analysis indicates that the latter is the primary driving force. We also observe policy differences between male- and female-controlled groups, though these are substantially smaller than the mean individual differences—a natural consequence of the aggregation of individual preferences into collective outcomes.

We look at gender differences among adolescents in Sweden in preferences for competition, altruism and risk. For competitiveness, we explore two different tasks that differ in associated stereotypes. We find no gender difference in competitiveness when comparing performance under competition to that without competition. We further find that boys and girls are equally likely to self-select into competition in a verbal task, but that boys are significantly more likely to choose to compete in a mathematical task. This gender gap diminishes and becomes non-significant when we control for actual performance, beliefs about relative performance, and risk preferences, or for beliefs only. Girls are also more altruistic and less risk taking than boys.

When every individual’s effort imposes negative externalities, self-interested behavior leads to socially excessive effort. To curb these excesses when effort cannot be monitored, competing output-sharing partnerships can form. With the right-sized groups, aggregate effort falls to the socially optimal level. We investigate this theory experimentally and find that while it makes correct qualitative predictions, there are systematic quantitative deviations, always in the direction of the socially optimal investment. Using data on subjects’ conjectures of each other’s behavior we investigate altruism, conformity and extremeness aversion as possible explanations. We show that deviations are consistent with both altruism and conformity (but not extremeness aversion).

Can we use the lens of dual-system theories to explain altruistic behavior? In recent years this question has attracted the interest of both economists and psychologists. We contribute to this emerging literature by reporting the results of a meta-study of the literature and a new experiment. Our meta-study is based on 22 experimental studies conducted with more than 12,000 subjects. We show that the overall effect of manipulating cognitive resources to promote the “intuitive” system at the expense of the “deliberative” system is very close to zero. One reason for this null result could be that promoting intuition has heterogeneous effects on altruism across different subgroups of subjects or contexts. Another reason could be that there simply is no real effect and that previously reported single results are false positives. We explore the role of heterogeneity both by performing a mediator analysis of the meta-analytic effect and by conducting a new experiment designed to circumvent the issue of potential heterogeneity in the direction of the effect of promoting intuition. In both cases, we find little evidence that heterogeneity explains the absence of an overall effect of intuition on altruism. Taken together, our results offer little support for dual-system theories of altruistic behavior.

We present the results of an experiment on voluntary contributions to a public good with a unique dominant strategy equilibrium in the interior of the strategy space. The treatment variable is the equilibrium contribution level. By increasing the equilibrium contribution level, we reduce the “strength” of the social dilemma. Though we observe that the average level of contribution rises with the equilibrium contribution level, the average rate of over-contribution is not affected in a systematic way. Over-contribution is statistically significant only at the lower level of equilibrium contribution but not at the higher levels. We show that the Anderson et al. (1998, Journal of Public Economics. 70, 297-323) logit equilibrium model which combines altruism and decision errors fits quite well our laboratory data.