We conduct an online experiment on Prolific in which participants work on a real effort task for three rounds. In the first round they receive piece rate pay, in the second they take part in a two-person tournament and in the third round they choose between tournament and piece rate pay. Prior to making their tournament entry decision in round 3, participants receive feedback whether or not they won the previous round's tournament. We vary whether the tournament in round 2 is fair (the best performer wins) or unfair (the best performer might lose) and, for unfair tournaments, vary whether participants find out whether they won or lost fairly or unfairly. We also elicit performance beliefs prior to the tournament entry decision, and collect socio-economic characteristics and personality traits in a final questionnaire.