stat

Saturday 2 November 2013

Levelling Seats

One of my interests is electoral systems - don't knock it; on many job applications for analyist roles I have written about this interest and emphasised how I use Excel for it - and one of the issues that has confused me is that of levelling seats. Now, I understand the basic idea - to ensure that election results are more proportional, but the application of it was confusing.

I'll take as my starting point the June 2009 elections to the European Parliament for the United Kingdom. The United Kingdom elects 73 Members of the European Parliament (in 2009 we actually elected 72, but in December 2009, an extra seat was awarded to the West Midlands.

Sweden uses a levelling seat system for its general elections, with 39 of the 349 members chosen this way. If we keep the same ratio then we would expect 8 MEPs to be elected on levelling seats. The remaining 65 MEPs would be elected on a regional basis:

Region or nation MEPs Current MEPs Reduction
Eastern England 6 7 1
East Midlands 5 5 0
London 7 8 1
North East England 3 3 0
Northern Ireland 3 3 0
North West England 7 8 1
Scotland 5 6 1
South East England 9 10 1
South West England 6 6 0
Wales 3 4 1
West Midlands 6 7 1
Yorkshire & Humberside 5 6 1

Next we're going to do something which will seem odd at first - we will consider the Europarties rather than the national parties in cases where national parties are in a Europarty. The reasons for this will become apparent in a moment. But for now, the results would be:

  • Alliance of European Conservatives & Reformists - 25 (Conservative 24, Ulster Unionist Party 1)
  • Party of European Socialists - 12 (all Labour)
  • UK Independence Party - 11
  • Alliance of Liberals & Democrats for Europe - 10 (all Liberal Democrat)
  • European Free Alliance - 3 (Scottish National Party 2, Plaid Cymru 1)
  • European Green Party - 2 (both Green Party of England & Wales)
  • Sinn Féin - 1
  • Democratic Unionist Party - 1

We can look at which MEPs elected in 2009 would not have been elected at this stage:

Region or nation MEP Party
Eastern England John Agnew UK Independence Party
London Marina Yannakoudakis Alliance of European Conservatives & Reformists
North West England Nick Griffin British National Party
Scotland Catherine Stihler Party of European Socialists
South East England Catherine Bearder Alliance of Liberals & Democrats for Europe
Wales John Bufton UK Independence Party
West Midlands Anthea McIntyre Alliance of European Conservatives & Reformists
Yorkshire & Humberside Andrew Brons British National Party

With these out the way, we now work out which parties get the 8 levelling MEPs. We are used to using d'Hondt for list systems, so this is the approach I will take here. Note that it doesn't really matter how the earlier members were elected before we get to this stage - for example, we could have levelling Members of the Scottish Parliament elected once all the first-stage MSPs had been elected under the Additional Members System.

The basic principle is to add together all the votes for the parties, and allocate the extra MEPs - so we divide the total vote for each party by one more than the number of MEPs it has. When we do this we find that the European Green Party and the British National Party are entitled to 3 levelling MEPs each, and the English Democrats and the Christian Party are each entitled to 1 levelling MEP. There is something intutive here - these are the minorish parties who just fail to win a seat in the regions, but add together their votes across the nation and we see they get enough to win seats.

Note that we are using the Europarties here - it could be possible that when we look at the Party of European Socialist vote, they are entitled to a levelling MEP in Northern Ireland, and so Labour voters in Great Britain would be helping elect a Social Democratic & Labour Party MEP. Notice I mentioned a levelling MEP in a particular place. Levelling members are not meant to represent the whole nation.

For the next stage is to find out where these levelling MEPs will represent. And to do this we use the Sainte-Laguë method in an unusual way. For each party that is entitled to levelling MEPs, we look at its vote and seats region-by-region, and work out a quotient of the number of votes divided by one more than twice the number of seats. The region with the highest quotient gets that party's first levelling MEP - and the process is repeated if more than one is to be elected.

For the parties with no MEPs in the first round and only entitled to one levelling MEP, it is simple. It is the region where they got their most votes. For the English Democrats, this is South East England, and the winner would be Steve Uncles, who was unsuccessful in his bid to become Kent's Police & Crime Commissioner - note that even though he would represent just South East England, he would owe his place to the votes his party got across the whole of England.

For the Christian Party, this is London and the levelling MEP would be George Hargreaves.

For the European Green Party and the British National Party it is a bit more complicated. But we find for the former the levelling MEPs are Ricky Knight in South West England, Rupert Read in Eastern England and Peter Cranie in North West England.

The British National Party would see Griffin and Brons elected as levelling MEPs, along with Simon Darby in the West Midlands.

So, the regional distribution would be:

Region or nation First stage MEPs Levelling MEPs Total MEPs Gain/Loss
Eastern England 6 1 7 0
East Midlands 5 0 5 0
London 7 1 8 0
North East England 3 0 3 0
Northern Ireland 3 0 3 0
North West England 7 2 9 +1
Scotland 5 0 5 -1
South East England 9 1 10 0
South West England 6 1 7 +1
Wales 3 0 3 -1
West Midlands 6 1 7 0
Yorkshire & Humberside 5 1 6 0

And that is how levelling seats are worked out.

Now, I did state earlier that it doesn't really matter how the earlier members were elected before we get to the levelling seats stage. Basically, all that it's interested in is how many votes a party has nationwide and how many seats that party has before the levelling seats are worked out.

With the Additional Members System in the United Kingdom, the lower-tier are always elected by Single Member Plurality. But it doesn't have to be - there could be all single-member constituencies using the Alternative Vote, or some multi-member constituencies using Single Transferable Vote. Take, for example, the May 2011 election to the Scottish Parliament and consider the Scotland North East region. 10 constituency members and 7 additional members elected using the d'Hondt system. But it doesn't have to be 10 constituencies - there could be just 7, with 5 of them returning 1 MSP, Aberdeen & North Kincardine returning 3 MSPs and Dundee returning 2 MSPs. When the allocation of additional members are worked out, all that matters is the regional vote and number of constituency MSPs for each party.

And that brings me on to how levelling seats would work with AMS. Note that they would not create a third tier of MSPs, rather that they would be an extra set of regional MSPs. If we look at the 2011 Scottish election, we get:

Party Constituency MSPs Regional MSPs Total MSPs
Scottish National Party 53 16 69
Labour 15 22 37
Conservatives 3 12 15
Liberal Democrats 2 3 5
Greens 0 2 2
Independent 0 1 1

Scotland is divided into 8 regions, which return between 8 and 10 constituency MSPs, and 7 regional MSPs. This gives us 129 MSPs in all. With the Swedish ratio, we would expect 14 levelling seats. We can round this up to 16 - equivalent to 2 levelling seats per region.

The first step is to simply allocate 5 regional MSPs for each region - so the sixth and seventh regional MSPs are not elected at this stage (but might be later). So, the MSPs who lose their seats at this stage are:

Region MSP Party
Glasgow Bob Doris* Scottish National Party
Anne McTaggart Labour
Highlands & Islands Jean Urquhart Scottish National Party
Mike MacKenzie Scottish National Party
Lothian Neil Findlay Labour
Gavin Brown* Conservative
Scotland Central John Wilson Scottish National Party
Clare Adamson Scottish National Party
Scotland Mid & Fife Willie Rennie Liberal Democrat
Annabelle Ewing Scottish National Party
Scotland North East Lewis Macdonald* Labour
Mark McDonald Scottish National Party
Scotland South Jim Hume* Liberal Democrat
Charles Brodie Scottish National Party
Scotland West Stuart McMillan* Scottish National Party
Neil Bibby Labour

[* MSP at the time of the election]

As we see, reducing the number of regional MSPs by 2 per regions sees the loss of 9 Scottish National Party, 4 Labour, 2 Liberal Democrat and 1 Conservative MSP, giving a result of:

Party Constituency MSPs Regional MSPs Total MSPs
Scottish National Party 53 7 60
Labour 15 18 33
Conservatives 3 11 14
Liberal Democrats 2 1 3
Greens 0 2 2
Independent 0 1 1

Now we'll look at how many levelling seats each party needs, but we'll do something different. In European countries that use levelling seats, it is common for them to be allocated on a more proportional system than then previous seats. So, with the regional seats allocated on d'Hondt, in this example we shall allocate the levelling seats to the parties using Sainte-Laguë. When we run this, we find that Labour, the Liberal Democrats and the Greens are all entitled to 4 levelling seats, the Conservatives entitled to 3, and the Scottish National Party to 1. Using the method above, we can then allocate them out:

Region MSP Party
Glasgow None
Highlands & Islands Eleanor Scott** Green
Lothian Neil Findlay Labour
Gavin Brown* Conservative
Ann Henderson Labour
Margaret Smith* Liberal Democrat
Scotland Central None
Scotland Mid & Fife Willie Rennie Liberal Democrat
Mark Ruskell** Green
Scotland North East Lewis Macdonald* Labour
Hugh Campbell-Adamson Conservative
Martin Ford Green
Scotland South Jim Hume* Liberal Democrat
Derek Brownlee* Conservative
Marie Rooney Labour
Alis Ballance Green
Scotland West Stuart McMillan* Scottish National Party
Ross Finnie* Liberal Democrat

[* MSP at the time of the election]

[** Former MSP]

One thing to note about levelling seats is that they are not distributed evenly across the regions.

The overall result with this would be:

Party Constituency MSPs Regional MSPs Total MSPs
Scottish National Party 53 8 61
Labour 15 22 37
Conservatives 3 14 17
Liberal Democrats 2 5 7
Greens 0 6 6
Independent 0 1 1

No comments:

Post a Comment