There’s a gender difference in how much buyers bid for identical items on eBay, according to a study in Science Advances as reported by the New York Times.  On new item auctions, where the product is easily identifiable and there’s no negotiation, buyers bid 20% less for items sold by women on average. 

The study, which looked at 630,000 transactions from 2009 to 2012 using data provided by eBay, controlled for seller reputation, experience, number of photos, use of bold lettering, description wording, and other elements.  Sellers considered to be stores were excluded from the study. 

The differences were not uniform across product category.  There were product categories, such as toys and pet products, on which women received higher prices than men.  And the price difference was only 3% on used items, vs. the 20% difference on new products.  Categories such as new video games had the biggest advantage for male sellers, with Nintendo Wii games producing an especially high gap between prices depending on seller gender.

The researchers, Tamar Kricheli-Katz, a professor of sociology and law at Tel Aviv University, and Tali Regev, an economist at IDC Herzliya, also conducted experiments.  One of the experiments asked study subjects to value a $100 gift card and varied the seller’s name to be either Alison or Brad.  The subjects valued the card sold by Alison at $83.34, and the card sold by Brad at $87.42 on average. 

The study and experiment indicate the importance of unconscious biases on commercial transactions, something that it’s important that both buyers and sellers keep in mind.