We consider the interaction of intrinsic motivation and concerns for social approval in a laboratory experiment. We elicit a proxy for Fairtrade preferences before the experiment. In the experiment, we elicit willingness to pay for conventional and Fairtrade chocolate. Treatments vary whether...

The conflict between pro-self and pro-social behaviour is at the core of many key problems of our time, as, for example, the reduction of air pollution and the redistribution of scarce resources. For the well-being of our societies, it is thus crucial to find mechanisms to promote pro-social...

We study the effect of repeated opportunities to behave pro-socially on aggregate pro-social behavior in two laboratory experiments and in field data on charitable giving. In the first experiment we show that two consecutive pro-social decisions (implemented as donations to a charity) lead to...

Customers write book reviews for Amazon.com and rate stores at BizRate.com. Car drivers call up radio stations to report traffic jams or radar traps. In many cases individuals share their information to the benefit of an unknown group of recipients, even though doing so is costly for the...

Christmas is when people are expected to act selflessly for the well-being of others, but are people actually more altruistic at this time of the year? Responding to this question poses a challenge because of the confounding factors of charitable tax breaks, reciprocity motives, direct social...

Concern about potential free riding in the provision of public goods has a long history. More recently, experimental economists have turned their attention to the conditions under which free riding would be expected to occur. A model of free riding is provided here which demonstrates that...

Disentangling the motivational drivers of individuals is frequently regarded a key step in reconciling theory and empirical evidence on the voluntary provision of public goods. We present results of a large online field experiments with 12,624 contribution choices by members of the...

This study analyzes the stability of preferences through the lens of psychological motives. We report the results of a public goods experiment in which subjects were induced with the motives of Care and Anger through autobiographical recall. Subjects' preferences, beliefs, and perceptions under...

This paper studies how imposing norms on contribution behavior affects individuals' intrinsic motivation. We consider the church levy, which the Catholic Church in Germany collects as a charitable donation, despite the fact that the levy is legally a tax. We design a randomized field experiment...

There has been little systematic study of the mechanisms typically used to raise money for charity. One of the most common is the simple raffle in which participants purchase chances to win a prize at a constant price. We conduct a field experiment randomly assigning participants to four raffle...