ADVERSE SELECTION IN ELECTRONIC MARKETS: EVIDENCE FROM ONLINE STAMP AUCTIONS
通过比较eBay与专业邮票拍卖网站MR的价格，发现eBay上买家价格低10-15%，且价差随邮票价值增加而扩大，证实了逆向选择的存在，同时卖家声誉对价格和成交概率影响有限。
We analyze adverse selection costs in online stamp auctions, based on a comparison of prices on eBay with those of matched stamps at a specialty stamps auction site in the U.S., Michael Rogers, Inc. (MR), which we know a priori has low quality uncertainty. We find that buyer prices are 10–15% lower on eBay as compared to MR, and the price difference, increases with the value of the stamps. Consistent with this adverse selection discount we find that the seller reputation mechanism on eBay has an economically modest, although statistically significant, effect on auction price and probability of sale.