Participants completed an online survey containing our power measure among other unrelated questionnaires. Following the survey, we presented participants with an opportunity to cheat using the paradigm established by Lammers et al. [14]. Participants were given the chance to enter into a lottery for a $50 gift card as compensation for completing the survey. The number of times they would be entered into the lottery would be determined by a dice roll. Participants were directed to a website (random.org) that simulated the roll of two standard, six-sided dice. Participants were instructed to roll the dice once, sum the two dice together, and then enter this number into the survey. Of course, participants were free to enter any number they chose. The dice roll was random and therefore logically unrelated to any personal characteristics. Thus, any systematic relationship between participants' characteristics and the number reported in the survey is indicative of cheating behaviour [14].

We expected that men with greater facial WHRs would report higher dice rolls. As the actual dice roll is completely random, any relationship between facial WHR and the reported rolls represents strong evidence that men with high facial WHRs are over-reporting the results of their roll (i.e. cheating). It is important to note that this paradigm allows us to capture cheating behaviour only indirectly. Indeed, our approach introduces potential noise to the data as, for example, men with smaller facial WHRs may legitimately roll and report higher dice totals. Thus, testing for cheating behaviour using this paradigm represents a conservative test of our hypotheses.