[klochner]

It's actually the multi-unit analogue of the first-price sealed bid auction.

Note that in FPSB you also don't have an incentive to report your true value, but it is revenue maximizing and efficient in expectation assuming risk-neutral bidders [1].

The basic gist of the proof is that everyone has an incentive to shade their bids down in proportion to the probability that their bid sets the price. The amount you shade is monotone in your valuation, so you end up with the same relative ordering of bids.

And the punchline is that you get the same winner and the same expected revenue for the Vickrey vs. FPSB.

[1] http://en.wikipedia.org/wiki/Revenue_equivalence_theorem#Rev...

[orijing]

Yeah, it might be what they were after, but their text (How much are you willing to pay?) suggests that your dominant strategy is to input your true value.

If that's what they're after, the text is misleading in my opinion...