Thoughts on politics and life from a liberal perspective

Monday, 24 January 2011

Paint and the Alternative Vote

This clip from Auf Wiedersehen Pet has being doing the rounds sparked by a post from Mark Wallace where he claims that it shows how AV is not a good system.






The clip shows the lads trying to decide what colour paint they should use to paint the hut. Because they can't agree on a colour Barry suggests they use a preferential voting system whereby everyone gets 2 choices, their first is weighted with two points and the second is weighted with one point. They then total them up to decide which colour wins. The result is yellow which was apparently nobody's first choice. Cue much hilarity from Mark and others who claim this shows AV is unfair. Mark does concede that the system is not AV but that the same result would have happened under AV too*.

According to Barry in the clip, of the 6 who voted, none of them chose the same first choice colour. Three of them chose yellow for second place so it wins with 3 points vs 2 for all the others that were first placed. We also need to assume that all the other second placed colours were different from those that came first, otherwise at least one of them would have had 3 points and hence it would have been a tie.

I am not so sure that this clip shows AV as being wrong or unfair. Mark implies that AV has chosen the wrong winner as yellow was nobody's first choice but in such an election with such a disparate variety of views amongst the electorate, how else were they supposed to choose the colour? Surely allowing preferences like this is fairer than just one person imposing their first choice view on everyone else despite it only being the first choice of under 17% of the electorate?

In fact, if anything a proper AV system would have been even more fair allowing each voter to express more information about their preferences and hence having an influence on the outcome.

Let's just move this scenario into the voting world for a minute. Let's imagine a constituency with a very diverse range of views amongst its electorate like this. Let's also imagine that like in the example from AWP above that first choice vote is very close, say around 16% to 17% for 6 parties. Something like:

Conservative 17.1%
Labour 16.9%
Lib Dem 16.7%
UKIP 16.6%
Green 16.4%
SNP 16.2%

This is about as close to the AWP example as the real world could ever get (it's never going to be an exact 1/6th split amongst all parties) and it is an extreme example but useful to work this through.

In a real world scenario it is statistically highly improbable that 0% of the electorate would opt not to choose a specific party as its first choice but that 50% would choose that party as its second choice as in the AWP example. Far more likely is a party that did not come first in first preferences overtakes the one in first place (but well short of 50%) after the second (and third and so on) preferences are taken into account.

Under First Past the Post the Conservative would take the seat with less than a fifth of the vote. Even if most of the supporters of all the other parties would prefer to have had a Labour MP, no account is taken of that.

So far from "proving" the case for FPTP, this example actually highlights the pernicious effect of First Past the Post.


*Incidentally, Duncan Stott in the comments on Mark's post refutes this claim in that if yellow had received no first preferences it would have been eliminated after the first round.

10 comments:

Hywel said...

Surely the real lesson is don't put Barry in charge of anything!

longrun2 said...

It is actually a better voting system than AV (who, outside an asylum, thinks a third choice should be worth as much as a first choice?) so defending AV on the basis that "Auf Wiedersehen Pet" didn't use exactly the same system as AV doesn't cut much ice.
Most of your objections to FPTP are overcome by tactical voting - the biggest distortion in the current system is due to the use of ten-years-out-of-date population data for determining constituency sizes, which may be why Labour is filibustering the bill in the "House of Lords".

Matthew Huntbach said...

A reasonable criticism of AV is that actually it DOESN'T have the effect claimed by Wallace. Given the way candidates are eliminated, a candidate who would be a good compromise choice becauses/he everyone's second choice but few people's first doesn't stand a chance because s/he gets eliminated early on.

Actually, the problem with AV is that it's everyone's second choice but few people's first. If we were electing electoral systems by AV, it would be the first to be eliminated, leaving its second preference to go to either FPTP or STV.

The mechanics of AV are really very simple, I would expect a primary school child to be able to manage it. I would like to live in a world where those who sign up to innumerate and illogical criticisms of it such as that offered by NO2AV were laughed off in the same way as they would be e.g. if they were to write letters full of spelling mistakes, or to suppose Shakespeare wrote "Great Expectations" or to suppose Mary Queen of Scots and "Bloody Mary" were the same person or some other mitskae which suggested the person lacked what is considered basic knowledge for a reasonably intelligent person. Why is it that in thos country people wodl be ashamed to admit to being illiterate, but seem to regard it as a mark of pride to be innumerate?

AV simply has the same effect as having a repeated ballot, under the resonable assumption that e.g. if the LibDem is eliminated it would not cause people who voted Labour to switch to Tory or vice versa so actually we only have to reconsider the votes of the eliminated candidates.

Another way of putting it is that AV gives the SAME RESULT that FPTP would give if all those candidates who were eliminated before an AV winner was achieved had never stood in the first place.

It is NOTHING AT ALL like a "points for preferences" system. Those who claim it is are either fools or liars, whichever, by making that claim they show they are not suitable people to be entrusted with any sort of political power. I mean this - do you want someone who canot understand the simple algorithm that is AV to be running this country? Or someone who does but who lies about it because s/he has no real good and genuine arguments for his/her case, which is really held ony out of self-interest.

Peter David said...

If these votes had been counted by AV, yellow would never have been selected.

There were six voters. The actual colours they voted for doesn't really matter but the results in the first round must therefore have been something like:

Pink 1
White 1
Orange 1
Black 1
Red 1
Green 1
Yellow 0
Blue 0
Teal 0

Under this scenario, yellow, blue and teal would have all been excluded. Under AV rules, the vote would then have been decided by randomly selecting between pink, white, orange, black or red. Of course, if the voters had used more than just a first and second preference then it is entirely possible that a consensus colour could have emerged.

Of course, if the poll had been done by FPTP then it would have resulted in a random selection as well. The only difference is that with AV there would have been a CHANCE of a consensus forming.

This is an argument against systems such as Daborda but only a cretin would pretend it is an argument against AV.

DBirkin said...

Well yellow is the best option as everyone is ok with it. However AV would have got rid of it. AV is hugely flawed like that

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bhashkar_BIM Services said...

The mechanics of AV are really very simple, I would expect a primary school child to be able to manage it. I would like to live in a world where those who sign up to innumerate and illogical criticisms of it such as that offered by NO2AV were laughed off in the same way as they would be e.g. if they were to write letters full of spelling mistakes, or to suppose Shakespeare wrote "Great Expectations" or to suppose Mary Queen of Scots and "Bloody Mary" were the same person or some other mitskae which suggested the person lacked what is considered basic knowledge for a reasonably intelligent person. Why is it that in thos country people wodl be ashamed to admit to being illiterate, but seem to regard it as a mark of pride to be innumerate?

bhashkar_suainlogistic said...

Surely the real lesson is don't put Barry in charge of anything! thanks....

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