We examine gender differences in willingness to compete for high stakes. When strategic considerations are absent, we observe the well-known pattern that women are less likely to compete than men, but this difference derives entirely from women avoiding competition against men. When the decision is strategic and contestants should factor in the competitiveness of others, women again avoid competing against men. Men then seem to anticipate the lower competitiveness of female opponents, as evidenced by their greater tendency to compete against women. The findings shed new light on the persistent gender gap at the male-dominated top of the career ladder.

Peer punishment is widely considered a key mechanism supporting cooperation in human groups. Although much research shows that human behavior is shaped by the prevailing social norms, little is known about how punishment decisions are impacted by the social context. We present a set of large-scale incentivized experiments in which participants (N=999) could punish their partner conditional on either the level of cooperation or the level of punishment displayed by others who previously interacted in the same setting. While many participants punish independently of levels of cooperation or punishment, a substantial portion punishes free riding more severely when cooperation is more common (‘norm enforcement’), or when free riding is more severely punished by others (‘conformist punishment’). With a dynamic model we demonstrate that conditional punishment strategies can substantially promote cooperation. In particular, conformist punishment helps cooperation to gain a foothold in a population, and norm enforcement helps to maintain cooperation at high levels. Our results provide solid empirical evidence of conditional punishment strategies and illustrate their possible implications for the dynamics of human cooperation.

Berger and Pope (2011) show that being slightly behind increases the likelihood of winning in professional and collegiate basketball. We extend their analysis to large samples of Australian football, American football and rugby matches, but find little to no evidence of such an effect for these three sports. When we revisit the phenomenon for basketball, we do find supportive evidence for National Basketball Association (NBA) matches from the period analyzed in Berger and Pope. However, we find no significant effect for NBA matches from outside this sample period, for collegiate matches, and for matches from the Women’s NBA. High-powered meta-analyses across the different sports and competitions do not reject the null hypothesis of no effect of being slightly behind on winning.

This paper reports the results of a large randomized field experiment that investigates the extent to which nudges can stimulate student participation in teaching evaluations. Three different nudges were tested: (1) heightening students? perceived impact of teaching evaluations, (2) communicating a descriptive norm of high participation, and (3) using the commitment-consistency principle by asking students to commit to participation. We find that none of the nudges was effective: all treatment effects were insignificant and close to zero in magnitude. Exploring heterogeneous treatment effects, we find evidence that the effectiveness of the commitment treatment differed across students: it increased participation among students with good average grades, whereas it decreased participation for students whose grades were poor. Overall, our results add to the body of evidence that demonstrates that nudges may not always be as effective as suggested in the literature.

This paper introduces the Prince incentive system for measuring preferences. Prince is a variation of the random incentive system that enhances isolation and makes incentive compatibility more transparent to subjects. It allows for the precise and direct elicitation of indifference values as with matching while having the clarity and validity of choice lists. Prince avoids the opaqueness of Becker-DeGroot-Marschak’s mechanism and precludes strategic behavior in adaptive experiments. Using Prince, we shed new light on willingness to accept and the major components of decision under uncertainty: utilities, subjective beliefs, and ambiguity attitudes. Prince outperforms a classical implementation of the random incentive system.