Saturday 4 December 2010

Really simple - one of the ways AV is better than FPTP.

Meat eaters read  this:

Under FPTP - if 79% of people in a group want burgers for dinner but evenly split between McDonalds, Burger King, Wimpy, Wendys, whereas 21% want a veggie Mung Bean Salad - then if every one votes for what they most want then every one ends up with nasty salad instead of tasty beef in a bun !! The Veggie option getting more votes than any other single option - but still on 21% of the votes.

Under AV - everyone would have ranked their choice of dinner - burger eaters probably putting the Bean Salad last (if ranking it at all). The first rounds of counting under AV would probably drop one or two of the burger joints, those voters having their vote moved to their next choice. Eventually the most popular burger joint would be selected (with over 50% of the counted votes).

Yes the vegetarian 21% would be disappointed, but if the option is 79% being disappointed - so be it.

Veggies read this:

Under FPTP - if 79% of people in a group want veggie food for dinner in Brighton but were evenly split between wanting to eat at FoodForFriends, TerreATerre, BombayAloo, WaiKikaMooKau, so the 21% who want Veal and Foie gras get to choose for everyone.

Under AV - everyone would have ranked their choice of dinner - vegetarians probably putting the Veal and Foie gras last (if ranking it at all). The first rounds of counting under AV would probably drop one or two of the veggie diners, those voters having their vote moved to their next choice. Eventually the most popular veggie joint would be selected (with over 50% of the counted votes).

Yes the carnivorous 21% maybe disappointed, but if the option is 79% being disappointed - so be it.

Everyone read this:

People who want their own way even if it means the majority are disappointed will prefer FPTP - as they can potentially win by persuading only 21% of people to agree with them. 79% will be disappointed, but what do they care if they have got their own way?

People who want their own way even if it means the majority are disappointed will prefer FPTP - as they can lean on others to vote 'tactically' the way they want them to, with threats of the most 'unwanted' option winning if they don't.

Party fanatics actively support FPTP (whether overtly or just by saying no to AV).

The rest of us, voters, will benefit from AV, parties will not.

5 comments:

  1. I have to admit that this is one of the best examples for AV I have read - a shame about 'fanatic' label though! :(

    My doubts are based on the 'equal weighting' afforded to 2nd choices over someone else's 1st choice - which I'm sure you've heard. Nevertheless I'll have to think about this in the light of your argument here :)

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  2. Thanks - I have de-fanaticised it a bit :-)

    I think this highlights that 'weighting' is a red-herring. The Burger eaters may not care *that* much about which burger bar they go to and they would happily vote 'tactically' for any of the burger bars to consolidate the burger vote and avoid salad. But why try and second guess all the other voters (and may be get it wrong) when AV cuts out this whole process and lets you just be honest.

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  3. Worth pointing out that this example isn't too far off what actually happens, too; lowest vote share of any MP in 2010 was 29%, in Norwich South.

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  4. Obvious solution would be to count everyone's preferences.

    Out of interest which parties would you consider the 4 similar parties and which one is the outsider? Because otherwise the example doesn't really ring true

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  5. DBirkin if you have a system that is 'obviously' better - feel free to propose it, maybe it will make its way into a future referendum on voting reform - right now the options are AV vs FPTP.

    There is nothing specific to 'ring true' this is just an example of how vote splitting under FPTP can let the least popular option win. A supporter of FPTP may argue that the winner is the 'most popular' but look at the argument, make your choice...

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