eBay has changed the way it determines a seller's Buyer Dissatisfaction Rate (BDR) used to measure seller performance. When a seller's BDR goes above 5 percent, eBay imposes a number of restrictions, including a new requirement that the seller accept PayPal or credit cards (part of its Safe Payment policy). eBay will also hold funds up to 21 days when PayPal is used to make a purchase from sellers with a BDR greater than 5 percent.

Formerly, eBay used negatives to determine Buyer Dissatisfaction Rates in its Seller Non Performance Policy, though customer service representatives could use other factors as well. Last year, eBay began using neutrals as well as negatives in a formula and stated that "neutrals are increasingly and almost always used as a measure as a sign of dissatisfaction with some part of the transaction" (http://www.auctionbytes.com/cab/abn/y07/m08/i30/s01). On Thursday, eBay told AuctionBytes it would now also factor in Detailed Seller Ratings (DSRs) of 1 and 2 (out of a 5-star rating system) into the BDR, though low DSRs are weighted less than a negative feedback rating. Neutrals have a weight of two-thirds of a negative weight.

A spokesperson told AuctionBytes on Thursday that the formula is part of a proprietary algorithm and the company could not disclose the specifics. He said eBay would adjust the formula as patterns of buyer behavior change over time.

eBay Trust & Safety's John McDonald said eBay does not take into account a buyer's history or number of feedback in the algorithm. Many sellers complain that most negative ratings they receive come from new buyers with less than 10 feedback.

See more information about the 21-day hold policy in this related story (http://www.auctionbytes.com/cab/abn/y08/m02/i08/s03).