To understand the "pure" incentives of altruism, economic laboratory research on humans almost always forbids communication between subjects. In reality, however, altruism usually requires interaction between givers and receivers, which clearly must influence choices. Charities, for example,...

If people get joy from giving, then why might they avoid fundraisers? We explore this in a randomized natural field experiment during the Salvation Army's annual campaign. The familiar bell-ringers were placed at one or both of two main entrances to a supermarket, making the ask for a charitable...

Large and thus statistically powerful A/B tests are increasingly popular in business and policy to evaluate potential innovations. We study how to optimally use scarce experimental resources to screen innovations. To do so, we propose a new framework for optimal experimentation that we call the...

We use five years of bidding data to examine the reaction of advertisers to widely disseminated press on the lack of effectiveness of brand search advertising (queries that contain the firm's name) found in a large experiment run by eBay (Blake, Nosko and Tadelis, 2015). We estimate that 11% of...

On search keywords with trademarked terms, the brand owner (“focal brand”) and other relevant firms compete for consumers. For the focal brand, paid clicks have a direct substitute in the organic links below the paid ad(s). The proximity of this substitute depends on whether competing firms...

We design a laboratory experiment to test for image motives in a setting where decisions signal intelligence to a social audience. Money-maximizing behavior in the experiment sorts subjects by academic ability, as measured by performance on verbal analogy questions, across two levels of question...

Online publishing, social networks, and web search have dramatically lowered the costs of producing, distributing, and discovering news articles. Some scholars argue that such technological changes increase exposure to diverse perspectives, while others worry that they increase ideological...

News consumers in many authoritarian countries read government-controlled sources even when independent sources are available. We test whether these choices reflect a preference for pro-government coverage versus persistent tastes for specific websites. We exploit textual data from news...

If being asked to give to charity stimulates an emotional response, like empathy, that makes giving difficult to resist, a natural self-control mechanism might be to avoid being asked in the first place. We replicate a result from a field experiment that points to the role of empathy in giving....