Gender differences in competitiveness are often discussed as a potential explanation for gender differences in education and labor market outcomes. We correlate an incentivized measure of competitiveness with an important career choice of secondary school students in the Netherlands. At the age...

We estimate the impact of changes in unearned income on the height and weight of young children in a developing country. As a source of income variation we use a change in the eligibility criteria for receipt of an unconditional cash transfer in Ecuador. Two years after families lost the...

We estimate the impact of changes in unearned income on the height and weight of young children in a developing country. As source of variation we use changes in the eligibility criteria for receipt of an unconditional cash transfer in Ecuador. Two years after families lost the transfer, which...

We use fluctuations of female sex hormones occurring naturally over the menstrual cycle or induced by hormonal contraceptives to determine the importance of sex hormones in explaining gender differences in competitiveness. Participants in a laboratory experiment solve a simple arithmetics task...

It is now generally accepted that some people are more altruistic, more trusting, or more reciprocal than others, but it is still unclear whether these differences are innate or a consequence of nurture. We analyse the correlation between handedness and social preferences in the lab and find...

How do people react to setbacks and successes? I introduce a new measure of challenge-seeking to determine the effect of winning and losing in a competition on the willingness to seek further challenges. Participants in a lab experiment compete in two-person tournaments and are then informed of...

We examine how multitasking affects performance. We also examine whether individuals optimally choose their degree of multitasking or whether they perform better under an externally imposed schedule. Subjects in our experiment perform two different tasks according to one of three treatments: one...