1 September 2010

Let's Have a Raffle

There is a horrible way to have proportional representation in single member constituencies.

Instead of counting the votes cast, draw one at random. That candidate is elected. The more votes a candidate receives, the greater the probability of them being elected.

At a constituency level, this is very unfair to the individual politicians, particularly those who don't get elected despite being the most popular. However on a national scale across all the different constituencies, the law of large numbers means the net result will tend towards one that closely represents the will of the people.

There are no wasted votes and no motivation for tactical votes. Every vote has just as much chance as any other, no matter where you live. At the moment, how much your vote matters is a postcode lottery, because First Past The Post creates safe seats where voters have no chance of determining the outcome of the election. Switching to a raffle system would move the unfair lottery element away from the electorate and onto the politicians themselves.

Of course politicians would hate this system, as it would be unfair to them, so it will never happen. However the FPTP-supporting politician should question why they are happy to make the system a postcode lottery for the electorate, but not a lottery for themselves.

The only way of running elections which is fair to both politicians and the electorate is multi-member constituencies.


Tom King said...

This reminds me of Isaac Asimov's 'Franchise' a bit. Have you read it?

Duncan Stott said...

I haven't, but I just read a plot summary. I can see some degree of procedural similarity, but I think its outcome is different. The computer in Franchise essentially sources the sole median voter - a kind of hyper-centrism where only the person in the extreme middle counts. I'd say its outcome is more similar to First Past The Post, as it also creates a tiny electorate that have all the influence... I plan on blogging about this soon.

Proportional representation seeks to have multiple representatives that best express the wide range of opinion within the electorate. That's what I argue is the whole point of democracy: to have all views represented, not just the middle's. The system described in Franchise sounds like it would achieve the exact opposite.

Joe Otten said...

So a party getting 40% of the vote in a 600 seat parliament would get on average 240 seats, but (a quick calculation reveals) this number would have a standard deviation of 12 seats i.e. 2% of the vote worth.

About a third of the time the number of seats for a 40% party will be outside the range 228-252. Is this tolerable?

The probability that a 38% party will get more seats than a 42% party is left as an exercise for the reader.

(I have assumed, wrongly, a uniform distribution of the votes. Actual distribution will reduce these numbers a little.)