If I’m reading the link (thanks VincentYu!) correctly, your first impression was right. In the graduate class, total amounts earned were [1.95, 1.90, 2.15, 2.50] in that order for consecutive auctions. In the undergraduate class, [2.30, 2.05, 4.25, 3.50].
The number of people playing (bidding) did decrease (graduate: [5, 3, 4, 2], undergraduate: [6, 4, 3, 2]) in each round, but a selection effect is insufficient to explain the increase in total earnings, since there’s no reason these “selected” people could not have bid equally as much in the first round.
ETA: Note that this is a two-highest-bidders-pay auction, not all-pay, so the increase in total earnings does reflect an average increase in individual bids as well.
Right, of course. Selection effect.
I think what confused me was that I took that to mean the total amount of money earned, not per-person.
If I’m reading the link (thanks VincentYu!) correctly, your first impression was right. In the graduate class, total amounts earned were [1.95, 1.90, 2.15, 2.50] in that order for consecutive auctions. In the undergraduate class, [2.30, 2.05, 4.25, 3.50].
The number of people playing (bidding) did decrease (graduate: [5, 3, 4, 2], undergraduate: [6, 4, 3, 2]) in each round, but a selection effect is insufficient to explain the increase in total earnings, since there’s no reason these “selected” people could not have bid equally as much in the first round.
ETA: Note that this is a two-highest-bidders-pay auction, not all-pay, so the increase in total earnings does reflect an average increase in individual bids as well.