The impact of the irrelevant : temporary buy-options and bidding behavior in online auctions

In a laboratory experiment, we investigate the impact of temporary buy-options on efficiency, revenues, and bidding behavior in online proxy-auctions when bidders have independent private valuations. We show that the introduction of a buy-option reduces efficiency and at the same time fails to enhance revenues. In particular, we observe that the former presence of a temporary buy-option lowers final prices in an auction (even though the option is no longer available once an auction has started). If bidders have imprecise information about their private value, auction prices are increasing in the price of the buy-option which suggests anchoring as an explanation. Surprisingly, the former presence of a temporary buy-option also tends to reduce final auction prices if bidders are perfectly informed about their private value. In fact, we demonstrate that bidders are reluctant to bid above the option price regardless of the precision of their private information and the price of the option.