> spent about $57M. I have no idea how many votes they were able to get for that money. With Quadratic Voting, they'd get 7,550.

Doesn't that make it seem likely that they would prefer to continue with their current strategy rather than use the money to buy votes then? It seems likely that they ended up with more than 7550 votes for their 57M, especially considering that 7550 votes would be a smaller proportion of total votes in a system where people could get more than one vote.

While very interesting, I don't think a system like this really addresses the main problems which are more to do with the need for an educated and informed populace than anything else.

This is a great point. We address it in great depth in the paper with Posner, Voting Squared (http://papers.ssrn.com/sol3/papers.cfm?abstract_id=2343956). QV helps here, a lot we hope, because most current expenditure on advertising is useful because it targets very indifferent swing voters who feel a duty to vote but do not care one way or the other. They can easily be swayed by noisy and wasteful advertising. But under QV they would not matter much as they would never cast more than a very small vote in either direction. On the other hand persuading those who really know an issue to feel a bit more strongly or less strongly would have a lot of value. This would make the sort of public discourse that was encouraged much more intelligent and mature, like investigative reports rather than slanderous or vacuous ad copy.

Here's another interesting thought: QV might reduce the influence of PACs by solving the principal-agent problem. PACs like Crossroads are not, in fact, wealthy people. They're pools of donations from many politically sympathetic individuals. People donate to PACs because they want to do more than cast their one vote on a particular issue.

But donating to a PAC is a really inefficient way to have a political effect. The rules governing PACs are so loose that the people controlling them can do anything they want with the money, including flying a private jet to Tahiti and drinking MaiTais during the election. Even more responsible PACs will probably not spend the money exactly the way the donor would. They might, for example, concentrate their spending on certain "key" elections and ignore the donor's favourite candidate. Or they might support all the candidates from a given party, when the donor only really cares about one of them.

With QV, the donor can put his money to work in exactly the way he wants. That might leave PACs with much less money to spend.

> With QV, the donor can put his money to work in exactly the way he wants. That might leave PACs with much less money to spend.

We can hope. I expect though that in general having your dollars have - by design - a quadratically decreasing power in vote purchasing is quickly going to give you less bang for your buck than spending it on manipulating the perceptions of others. There'll be some cross over position in value, and people will spend $x on votes and the rest on manipulating/persuading others which is what PACs are for.

To reiterate kybernetikos's point:

if Crossroads can get more than 7,550 votes today for their $57M, they can get more than 7,550 votes tomorrow for the same $57M without skipping a beat, by pre-bribing the electorate to make 1 vote each.

So this doesn't seem to change much from Crossroads' point of view.

It doesn't look as though Quadratic Voting should have any effect on lobbying.