[EM] "Market based voting" paradigm. Revolutionary(?) design idea for multiwinner election schemes.

[Kristofer Munsterhjelm]

Warren Smith wrote:
>> One possible problem of the market paradigm is this: in a market, there
>> are buyers and sellers. The market finds a clearing price so that supply
>> balances demand. While the exchange of money can be emulated on one end
>> by the voters providing "money", it is not clear for what the candidates
>> use that money.
> 
> --they don't. Unlike in 'asset voting' the candidates in this system
> are uninvolved.
> They are passive participants, it is like buying a pizza.  Do we
> complain "it is not clear for what the pizzas use the money they
> receive?" No.  It's a nutty question.

Well, from the pizza's point of view, it doesn't matter who gets the 
pizza, as long as someone gets it. An auction satisfies certain 
desiderata for buyers (such as that the more you give, the greater the 
chance that you get what you want; that you have nothing to lose by 
being honest in the case of Vickrey, etc), but these are also desiderata 
for sellers (that one couldn't hypothetically do arbitrage and be better 
off, for instance).

In your case, the buyers are the voters. They bid using an account of 
pseudo-money. However, who are the sellers? In your Vickrey example, it 
doesn't matter, because the buyers' desiderata are the only thing we 
care about (such as the strategyproof nature of isolated buyers in a 
Vickrey auction). However, if we're to turn to more general auctions, 
then it may become a problem.

For instance, consider an auction with a reservation price. In ordinary 
auctions, the sellers set that price; but in the voting equivalent, I 
can't see who the sellers would be (the candidates? Candidate withdrawal 
option? 36.9 ultimatum?).

You might say, so what? Just focus on the buyers' desiderata. But then 
we might overlook solutions that don't exist as auctions because the 
sellers would never agree to them; and conversely, some auctions or 
other bargaining methods may be unsuited to voting methods because the 
sellers (whoever they are) are part of it, such as with determining a 
reserve price.

Rather than consider the methods auctions, it might be better to 
consider them general markets, where everybody are buyers and sellers. 
However, this introduces more complex strategies: buying something 
because you know someone else would pay more for it, etc., and I suppose 
the same question arises in that the money is not really money, and so 
there's little point in minimizing it except for that it gives you more 
freedom in the end (if more money buys a greater chance of having a seat).