Can somebody explain this bidding anomaly on CBID?

[craigchilds]

Originally Posted by ChasDen

What ever the bid increment is, the computer keeps bumping until it gets to the end. It cant go back and say you couldn't beat the first guy so lets drop the price back to where it was. When you changed the bid from 1 to 3 you changed it for all 3.

Chas

You are right, of course. As I mulled your answer, it finally clicked in my head how the CBid alogorithm works.

When I placed my bid, I assumed a bid for multiple units (boxes) would be evaluated "the eBay way", which is in terms of quantity requested vs quantity available. eBay logic says "There is one unit with no competing bids, so CC wins at $28. There are competing bids for units #2-3, so highest bidder (MN) wins at lower bidder's maximum price."

But the program is not written this way. CBid logic is written to maximize profit on every unit sold. There is a constraint in the bidding process that is not present in eBay: CBid will not allow a bidder who is placing a single bid on multiple units to win those units at different prices. If the price of any unit gets bid up because it competes with another bid, then the price of all remaining units will go up as well, even if no other user has bid on those remaining units.

I think this is what BigBen was trying to say earlier. Except he misspoke when he said all units in a lot must be sold at the same price. They can be sold at multiple prices, but not to the same user.

Is there a way to get around this constraint? Not that I can see. What would have happened if I submitted three separate bids, for a single unit each (rather than a single bid for three units)?

After 1st bid:

1. MN $28 2 of 2
2. CC $28 1 of 1

After 2nd bid:

1. MN $37 2 of 2
2. CC $37 1 of 1

After 3rd bid:

1. MN $37 2 of 2
2. CC $37 1 of 1

Seperate bids don't change the outcome of the auction, because my subsequent two bids, in effect, compete with my first bid to drive the price up to the maximum.

I don't know if this explanation makes sense to anyone else -- but it is clear to me now.