On the effects of joint bidding in independent private value auctions: An experimental study

► The effect of joint bidding in first-price auctions is studied experimentally. ► The results are partially consistent with risk-averse Nash equilibrium predictions. ► The decrease in the sellerʼs revenue is lower than expected while efficiency rises. ► The incentives to bid jointly are higher than anticipated. ► The effect of group decision-making is also studied.