This Ph.D. thesis in Economics consists of four self-contained chapters that empirically explore sources of economic inequality, using data from experiments, sports competitions, and Swedish registers. Competing biases: Effects of gender and nationality in sports judging explores in-group biases among judges in the equestrian sport dressage – the only Olympic sport with subjective performance evaluations in which male and female athletes compete as equals. International dressage competitions provide a rare opportunity to investigate gender bias and nationalistic bias in the same setting, using naturally occurring data on decisions of professional decision makers. Gender differences in initiation of negotiation: Does the gender of the negotiation counterpart matter? experimentally investigates how gender differences in the willingness to enter a wage negotiation are affected by whether the counterpart is a man or a woman. The importance of family background and neighborhood effects as determinants of crime uses Swedish register data to estimate sibling and neighborhood correlations in criminal convictions and incarceration. Omission effects in fairness behavior experimentally tests if individuals are more prone to act selfishly if they can passively allow for a self-serving outcome to be implemented rather than having to make an active choice. / <p>Diss. Stockholm :  Stockholm School of Economics, 2014. Introduction together with 4 papers</p>