Shill Bidding on eBay: a Case Study
Hi Dan 21,
I really don’t mean to offend but you are either one of that class of people commonly referred to as “idiots” or you are an eBay seller who is happily taking advantage of the obvious flaws in eBay’s proxy bidding system. I’ll give you the benefit of the doubt and assume that you fall somewhere in between.
You state that you have read my post, and indeed you quote the portion that explains how we know that the shill bidder knew that he had equaled the maximum value of the other bidder’s proxy bid. But, apparently you do not understand the logic of that statement. I will try to explain it more clearly:
Whenever a bid is placed:
if you are the first bidder, then, regardless of the value of your proxy bid, your bid will be displayed as equal to the starting bid set be the vendor;
if there is already a bid on the item, and your bid is [i]less[/i] than the maximum proxy bid of the high bidder, then you will become the underbidder displaying a bid equal to your maximum proxy bid, and the high bidder’s automatic bid will automatically advance one increment (or part thereof) above your maximum bid;
if there is already a bid on the item, and your bid is [i]greater[/i] than the maximum proxy bid of the high bidder, then you will become the high bidder displaying an automatic bid equal to one increment (or part thereof) above the maximum bid of the previous high bidder, who then becomes the underbidder at his maximum bid;
if there is already a bid on the item, and your bid happens to be [i]equal to[/i] that of the maximum proxy bid of the high bidder, then you will become the underbidder and the other bidder will remain the high bidder, with both parties displaying identical bid values.
Therefore, if the bids of the high bidder and the underbidder display as equal, that can only be because the maximum bids of both parties are indeed equal. I’m sorry, but I can’t explain it any better; if you still don’t understand …
On the matter of eBay’s statement to Metz that a seller would never risk shilling:
Here is a “Power” seller (123,000 feedback) who has a shill surreptitiously setting a “reserve” on his auctions.
The shill is “l***n” and he shows up on many of this sellers auctions, as is recorded on his Bid History Details page at
30-Day Summary: Total bids: 1277; Items bid on: 1117; Bid activity with this seller: 95% !!!
Hello? The stats are so patently obvious. What can one say, other than, so much for eBay’s absurdly disingenuous claim that they have “sophisticated” tools for the detection of such activity; and, yes, there are fairies at the bottom of the garden, too.
The real shame is that this activity (the surreptitious setting of a reserve) is encouraged by the eBay fee structure; no doubt eBay could design a fee structure that would remove the "need" for sellers to so behave; unfortunately, it appears that they do not have the intellect to understand the problem in the first place.