New Seat Details - Highland Central

This page shows the detail of the calculations performed to estimate the general election result for 2017 had the new boundaries for Highland Central been in force at that time. The basic idea of the calculation is to look at the district council wards which make up the new seat, and estimate how they voted in 2017. This estimate is based on the recent local election results in those wards, with adjustments made to allow for different turnouts and different voting patterns for local and general elections.

In many cases, wards are divided between several old constituencies or between new constituencies. So the same ward may be shown more than once, but the electorate shown will reflect that ward sub-section.

Election results from a recent local election are given. This is usually the local election closest to 2015 from the period 2012-2015. For multiple-member wards, the votes shown are the sum of the votes cast for all candidates of each party. A negative number indicates candidate(s) elected unopposed.

Calculation method

There are two problems with using the raw (actual) local election results to imply general election results ward-by-ward. Firstly, turnout can be different between local and general elections, which means that the total number of local votes cast does not equal the number of votes cast in each old seat at the general election. To correct for this, we adjust the local votes to match the general election turnout. Each ward's result is scaled, whilst keeping constant the percentage support for each party, so that the total turnout adds up to the old seat's general election turnout. All wards in the old seat are assumed to have the same percentage turnout.

Party	Implied 2017 Votes	Implied 2017 Share
SNP	22,124	39.5%
CON	16,384	29.2%
LAB	8,711	15.5%
LIB	8,157	14.5%
OTH	705	1.3%
SNP Majority	5,740	10.2%

Secondly, even though we now have the correct number of votes in the old seat, the party totals will not match the general election result. Some parties do better at the local election than the general election, and others do vice versa. We call these strong and weak parties respectively. The next step is to transfer votes from strong parties to weak parties. This is done by taking votes proportionally away from strong parties and putting them in a transfer pool. For instance if a party got 12,500 local votes, but only 10,000 general election votes, it will lose 20% over all the wards. These votes in each ward will be put in the ward's transfer pool and allocated to the weak parties. Weak parties will get votes transferred to them in proportion to the votes they need over the old seat. For instance, if two weak parties need 4,000 and 1,000 votes respectively, the first party will get 80% of each ward's transfer pool and the second party will get 20% of each ward's transfer pool. The transfer of votes between parties is done using the Electoral Calculus Transition Model.

Highland Central: Map

List of old seats forming part of Highland Central

Old seat: Inverness Nairn Badenoch and Strathspey

The table shows the transfer-adjusted results for each ward in the old seat of Inverness Nairn Badenoch and Strathspey, as well as showing which new seat each ward is in.

Old seat: Inverness Nairn Badenoch and Strathspey				Transfer-adjusted Results
District	Ward	Electorate 2017	New Seat	CON Votes	LAB Votes	LIB Votes	UKIP Votes	Green Votes	SNP Votes	MIN Votes	OTH Votes	Total Votes
Highland	Aird and Loch Ness	6,481	Highland Central; Highland North	1,620	358	464	0	0	1,817	0	63	4,322
Highland	Badenoch and Strathspey	9,852	Highland Central	2,256	887	802	0	0	3,038	0	91	7,074
Highland	Caol and Mallaig	32	Highland Central	8	3	2	0	0	9	0	0	22
Highland	Culloden and Ardersier	8,578	Highland Central	2,013	878	714	0	0	2,417	0	62	6,084
Highland	Inverness Central	8,943	Highland Central	1,725	1,981	621	0	0	2,881	0	102	7,310
Highland	Inverness Millburn	5,945	Highland Central	1,223	1,182	421	0	0	1,613	0	40	4,479
Highland	Inverness Ness-Side	8,557	Highland Central	1,879	1,034	980	0	0	2,165	0	61	6,119
Highland	Inverness South	10,213	Highland Central	2,198	733	1,176	0	0	2,584	0	62	6,753
Highland	Inverness West	6,548	Highland Central	1,241	685	740	0	0	1,699	0	42	4,407
Highland	Nairn	9,081	Moray and Nairn	1,956	812	559	0	0	2,819	0	87	6,233
	Total	74,230		16,119	8,553	6,479	0	0	21,042	0	610	52,803

Old seat: Ross Skye and Lochaber

The table shows the transfer-adjusted results for each ward in the old seat of Ross Skye and Lochaber, as well as showing which new seat each ward is in.

Old seat: Ross Skye and Lochaber				Transfer-adjusted Results
District	Ward	Electorate 2017	New Seat	CON Votes	LAB Votes	LIB Votes	UKIP Votes	Green Votes	SNP Votes	MIN Votes	OTH Votes	Total Votes
Highland	Aird and Loch Ness	2,739	Highland Central; Highland North	514	140	319	0	0	785	0	33	1,791
Highland	Black Isle	8,256	Highland North	1,759	468	1,282	0	0	2,215	0	100	5,824
Highland	Caol and Mallaig	6,534	Argyll, Bute and South West Highland; Highland Central	1,318	596	855	0	0	2,069	0	93	4,931
Highland	Dingwall and Seaforth	8,901	Highland North	1,605	1,091	1,424	0	0	2,653	0	106	6,879
Highland	Eilean a' Chèo	8,056	Highland Central	1,373	588	1,318	0	0	2,390	0	105	5,774
Highland	Fort William and Ardnamurchan	8,041	Argyll, Bute and South West Highland	1,345	1,266	954	0	0	2,685	0	99	6,349
Highland	Wester Ross, Strathpeffer and Lochalsh	9,373	Highland Central; Highland North	1,647	546	1,890	0	0	2,683	0	139	6,905
	Total	51,900		9,561	4,695	8,042	0	0	15,480	0	675	38,453

The full details of these calculations are given on the Ross Skye and Lochaber seat details page. Click on "Show workings".

New seat: Highland Central

District	Ward	Electorate 2017	Old Seat	CON Votes	LAB Votes	LIB Votes	UKIP Votes	Green Votes	SNP Votes	MIN Votes	OTH Votes	Total Votes
New seat: Highland Central
Highland	Aird and Loch Ness	4,937	Inverness Nairn Badenoch and Strathspey	1,271	281	364	0	0	1,426	0	49	3,391
Highland	Aird and Loch Ness	612	Ross Skye and Lochaber	126	34	78	0	0	192	0	8	438
Highland	Badenoch and Strathspey	10,295	Inverness Nairn Badenoch and Strathspey	2,256	887	802	0	0	3,038	0	91	7,074
Highland	Caol and Mallaig	3,009	Ross Skye and Lochaber	576	261	374	0	0	905	0	41	2,157
Highland	Caol and Mallaig	32	Inverness Nairn Badenoch and Strathspey	8	3	2	0	0	9	0	0	22
Highland	Culloden and Ardersier	8,854	Inverness Nairn Badenoch and Strathspey	2,013	878	714	0	0	2,417	0	62	6,084
Highland	Eilean a' Chèo	8,055	Ross Skye and Lochaber	1,373	588	1,318	0	0	2,390	0	105	5,774
Highland	Inverness Central	10,639	Inverness Nairn Badenoch and Strathspey	1,725	1,981	621	0	0	2,881	0	102	7,310
Highland	Inverness Millburn	6,517	Inverness Nairn Badenoch and Strathspey	1,223	1,182	421	0	0	1,613	0	40	4,479
Highland	Inverness Ness-Side	8,905	Inverness Nairn Badenoch and Strathspey	1,879	1,034	980	0	0	2,165	0	61	6,119
Highland	Inverness South	9,827	Inverness Nairn Badenoch and Strathspey	2,198	733	1,176	0	0	2,584	0	62	6,753
Highland	Inverness West	6,412	Inverness Nairn Badenoch and Strathspey	1,241	685	740	0	0	1,699	0	42	4,407
Highland	Wester Ross, Strathpeffer and Lochalsh	2,888	Ross Skye and Lochaber	494	164	567	0	0	805	0	42	2,072
	Total	80,982		16,383	8,711	8,157	0	0	22,124	0	705	56,080

And these are the implied results for 2017 for the new seat of Highland Central. Please note that the wards used are those of 2015 in order to be consistent with those used by the Boundary Commissions.

Implied MP at 2017:	Drew Hendry (SNP)
County/Area:	Highland (Scotland)
Electorate:	80,982
Turnout:	69.3%

Highland Central: New Boundaries 2018 Calculation

Highland Central: Overview

Introduction