The fog machine that I wrote about last week closed at �437.95 on Bumblebee Auctions yesterday. It was won by a proxy bid. The proxy bid facility in the system allows a user to set a limit on how much he or she is prepared to pay and leave the system to bid on his or her behalf. This means, of course, that a winning proxy bid will frequently be less than the limit the user set. Who can tell how high the winner might have been prepared to go in this case?
Bumblebee Auctions has to be fair and to be seen to be fair, so it makes the bid history for every lot publicly available on the internet. This can reveal some interesting bidding tactics. The bid history for the fog machine shows that the top bid had only got up to �30.45 on Monday and things didn't really start to get interesting until just before the auction was due to close.
The system has been specifically designed and configured to give a bidder a good chance of winning an item in which he or she is interested. In order to ensure this, we thought that the system should give a user a reasonable opportunity to respond to a rival bid as it would be frustrating for buyers to lose an item right at the last minute with little or no time to respond and place another bid.
The problem was addressed by introducing automatic auction extensions, so if a user places a bid in the last 10 minutes of an auction, the deadline is extended (by 10 minutes) to give someone else a chance. (The system sends the previous high bidder an email when a new high bid is received).
I think this worked well in the case of the fog machine, it can be seen that a bid was made at 20:32:16 (25 seconds before the before the original 20:32:41 end time) and that a counter bid was made at 20:33:43. Overall there were two ten minute extensions during which the price to be paid increased by nearly �200.
(Extensions also protect us from disputes arising from connection latency and PC clock disparities.)
I'd be interested to hear any suggestions for improvements.