Contents

Proportional Representation

Contents

Based on the results page from BBC, I hacked together a small Python script that assumed direct proportional voting in the UK and made a table comparing the First-Past-The-Post result (FPTP) to the Proportional Representation (PR) vote. Of course, PR can be implemented in a number of ways, including Single Transferable Vote, which I tend to prefer (that was a voting system geek joke. If you understood it, you win), and each may give slightly different results. But in general this gives us a gist of what kind of results we might have seen…

<th>
  FPTP seats
</th>

<th>
  PR seats
</th>
<td>
  306
</td>

<td>
  235
</td>
<td>
  258
</td>

<td>
  189
</td>
<td>
  57
</td>

<td>
  150
</td>
<td>
</td>

<td>
  20
</td>
<td>
</td>

<td>
  12
</td>
<td>
  6
</td>

<td>
  11
</td>
<td>
  1
</td>

<td>
  7
</td>
<td>
  1
</td>

<td>
  6
</td>
<td>
  5
</td>

<td>
  4
</td>
<td>
  8
</td>

<td>
  4
</td>
<td>
  3
</td>

<td>
  4
</td>
<td>
  3
</td>

<td>
  2
</td>
<td>
</td>

<td>
  2
</td>
<td>
</td>

<td>
  1
</td>
<td>
  1
</td>

<td>
  1
</td>
<td>
</td>

<td>
  1
</td>
<td>
</td>

<td>
  1
</td>
<td>
</td>

<td>
</td>
<td>
</td>

<td>
</td>
<td>
</td>

<td>
</td>
<td>
</td>

<td>
</td>

The “other” category is interesting. The “other” who got the seat in the FPTP system was Down North independent Sylvia Hermon, a clear winner with 63.1% of the votes. She would hold her seat in most PR systems, but not all – depending on whether there’s a bias towards regional results or not.

It’s very hard to see which “others” would get the other 6 seats under PR, because the data sets aren’t made available for download, but PR actually tends to favor “issues based politics” over “locale based politics”, meaning that fringe groups or single issue parties with small but spread out support would stand a chance. Actually, that’s the bulk of the reason Liberal Democrats would come so much better out of PR than FPTP – unlike Conservatives and Labor, they don’t really have strongholds as such, just a very well spread out support base throughout the country.

It’s interesting that UKIP and BNP would share 32 seats under PR. They are essentially the UK Nazi parties for all intents and purposes, although UKIP are far more moderate (and actually, occasionally reasonable). There was speculation on this on the Telegraph:

The Liberals only want a PR system because it ensures they would gain extra seats in future Parliaments, but it also means that there is a very real chance that a number of unsavoury fringe parties would also benefit. E.g. under a PR system the BNP would have gained around 11 seats in the next Parliament purely on the number of votes cast in their favour. Or would Clegg and his PR acolytes then want to ban all those small single issue parties they considered ‘unsuitable’ to stand in elections?.

Single issue parties are actually really important, because although they’re not particularly powerful, they manage to be “the elephant in the room”, forcing parliament to consider issues they’d otherwise gladly avoid or take a stance of convenience on. My favorite example of this is of course the Pirate Party – whilst its UK branch completely failed to do what “digital natives” are supposed to do best, namely aggregate, disseminate and publicize information, they’ve got a fair amount of support in Sweden and Germany, and their position there has forced a much more sensible discussion about ICT-related issues, privacy issues, and so on, where earlier those issues have been pushed through with little deliberation or understanding.

[I could write a long rant about how not to run an election campaign based on having followed PPUK’s progress in the last couple of weeks - they were definitely trying hard, but they were doing it all wrong. It should be noted that I’m not a Pirate Party supporter as such, although I do often wear a lapel pin that I stole from Mab - I’m just very much in agreement with their policy and platform, if not methodology, generally speaking, and I enjoy following their development.]

Anyway. It’s hard to say that PR is necessarily the best system. I’d actually prefer direct democracy, possibly with ad-hocratic vote proxying (I’ll explain that one later)… but it’s very hard to say that FPTP voting is a sensible system in anything larger than a elementary school class president elections or something like that.

Single Transferable Vote systems vary as well. Iceland doesn’t actually use STV, although it uses something mildly akin to it. It’s a closed list system where the votes are transferable, and they transfer by rotating clockwise through the constituencies. There are six constituencies in Iceland, and since Reykjavík North is the last constituency, it’s the one that will by default be counted last on the STV circuit, and therefore stands a higher chance than other constituencies to receive “cumulative seats” as a result of transfer.

Both in Iceland and the UK – and generally anywhere that isn’t going to go for some form of direct democracy – I’d suggest using a Schulze style STV system. The beauty of Schulze STV is that in addition to having a Single Transferable Vote, a Condorcet winner is announced, which could be a wonderful way to pick the Prime Minister. If there is no Condorcet winner, the result set is pruned (by the Schulze method) by removing anybody who is a pairwise loser in every case, and then the Condorcet winner is recalculated. This process is repeated until there’s a maximal set with a Condorcet winner.

Then you need a “preference” system. Using a geography based preference system is tricky, but allowing people to select one of their neighboring constituencies as a transfer preference would be resolvable. If votes need to travel through more than one constituency, they’d simply follow majority (or proportional) transfer preference in each constituency they encounter until resolution has been acheived. It’d make counting the votes a bitch, and be a horribly untransparent system, requiring people to have a fairly deep understanding of cascades (or, as a simplification, Markov chains) to fully fathom, but I think it’d be quite fair. Perhaps fairness doesn’t count for much if nobody understands how fairness is achieved.

Plus: Is a fair system also just? [beware: MS Word document!]

Anyway. That’s a few ¢ worth of food for thought… hopefully #dontdoitnick will pan out and the UK parliament will be hung for a couple of months, then dissolve into general elections under a new system.

Update: @samgoodby and @Robert_Sprigge have been tweeting about STV in relation to the UK elections. Check out: http://www.alternative-election.org.uk/