characteristics are observed. Students are randomly assigned to a tournament scheme that fosters competition between coupled students … which students can neither compete, nor cooperate. In line with theoretical predictions, we find that competition induces … higher effort with respect to cooperation and cooperation does not increase effort with respect to the baseline. However …

scarcer and hence competitive pressure is higher. By contrast, levels of cooperation are very similar across areas. This … indicates that scarcity does not hamper cooperation, at least as long as a subsurvival level has not been exceeded. Our data …