Menstrual Cycle and Competitive Bidding

Abstract

In an experiment using two-bidder first-price sealed-bid auctions with symmetric independent private values and 400 participants, we collected information on the female participants' menstrual cycles and the use of hormonal contraceptives. We find that naturally cycling women bid significantly higher than men and earn significantly lower profits than men except during the midcycle when fecundity is highest. We suggest an evolutionary hypothesis according to which women are predisposed by hormones to generally behave more riskily during their fecund phase of their menstrual cycle in order to increase the probability of conception, quality of offspring, and genetic variety. We also find that women on hormonal contraceptives bid significantly higher and earn substantially lower profits than men. This may be due to progestins contained in hormonal contraceptives or a selection effect. We discuss how our study differs from Chen, Katuščák, and Ozdenoren (2012).

The impact of the menstrual cycle and hormonal contraceptives on competitiveness

“…But these papers specifically look at behaviours which increase the risk of falling victim to rape and not at general risk attitudes. Also, risk aversion theoretically leads to higher bidding in first-price auctions and the findings of Chen et al (2009) and Pearson and Schipper (2009) are thus consistent with a negative impact of hormones on risk aversion. But these papers do not investigate directly whether the impact of the cycle on bidding is mediated via an impact on risk attitudes.…”

“…Chen et al (2009) find that contraceptive takers bid higher during and immediately after the pill break while there is no significant variation in bidding over the natural cycle. Pearson and Schipper (2009) find that bidding is higher during the premenstrual and menstrual phases. Although both papers devote substantial space to discussing the differences in their results, it is worth pointing out that both find bidding to be higher during phases when hormone levels are low and which according to our results coincide with increased competitiveness.…”

“…Chen et al (2009) find that bidding fluctuates over the menstrual cycle for users of hormonal contraceptives only. In a replication, Pearson and Schipper (2009) also find significant, but partially contradictory, fluctuations. Since the first version of this paper has been released, one other study concerned with the impact of the menstrual cycle on competitiveness has appeared (Wozniak et al, 2010).…”

The Menstrual Cycle and Performance Feedback Alter Gender Differences in Competitive Choices

“…They find bidding differences in first-price auctions between females with higher bids for females in the follicular phase versus females in the luteal phase though most of this variation is found to be driven by contraceptive users. In contrast, Pearson and Schipper (2009) find that women bid higher than men and earn lower profits only during the menstrual and premenstrual phases of the cycle when estrogen and progesterone levels are lower. Another between subject experimental study, Buser (2010), finds that in all-female groups, females participating during high levels of progesterone tend to be less competitive.…”

Choices About Competition: Differences by Gender and Hormonal Fluctuations, and the Role of Relative Performance Feedback

“…In contrast, Pearson and Schipper (2009) In the following section, I explain the experimental design used to examine both the effects of relative information and hormones on competitive environment selection.…”