New Seat Details - Wolverhampton South and Coseley

This page shows the detail of the calculations performed to estimate the general election result for 2017 had the new boundaries for Wolverhampton South and Coseley 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
LAB	22,455	51.7%
CON	17,741	40.8%
UKIP	2,198	5.1%
LIB	570	1.3%
Green	472	1.1%
LAB Majority	4,714	10.9%

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.

Wolverhampton South and Coseley: Map

List of old seats forming part of Wolverhampton South and Coseley

Old seat: Dudley North

The table shows the transfer-adjusted results for each ward in the old seat of Dudley North, as well as showing which new seat each ward is in.

Old seat: Dudley North				Transfer-adjusted Results
District	Ward	Electorate 2017	New Seat	CON Votes	LAB Votes	LIB Votes	UKIP Votes	Green Votes	NAT Votes	MIN Votes	OTH Votes	Total Votes
Dudley	Castle and Priory	11,018	Dudley	2,942	3,689	50	393	41	0	0	0	7,115
Dudley	Gornal	10,502	Dudley	3,357	2,481	66	362	36	0	0	0	6,302
Dudley	Sedgley	9,797	Wolverhampton South and Coseley	3,419	1,891	78	323	39	0	0	0	5,750
Dudley	St James's	9,842	Dudley	2,766	3,226	62	356	40	0	0	0	6,450
Dudley	St Thomas's	9,781	Warley	2,509	4,049	39	347	43	0	0	0	6,987
Dudley	Upper Gornal and Woodsetton	10,114	Wolverhampton South and Coseley	3,073	2,755	73	363	41	0	0	0	6,305
	Total	61,054		18,066	18,091	368	2,144	240	0	0	0	38,909

The full details of these calculations are given on the Dudley North seat details page. Click on "Show workings".

Old seat: Wolverhampton South East

The table shows the transfer-adjusted results for each ward in the old seat of Wolverhampton South East, as well as showing which new seat each ward is in.

Old seat: Wolverhampton South East				Transfer-adjusted Results
District	Ward	Electorate 2017	New Seat	CON Votes	LAB Votes	LIB Votes	UKIP Votes	Green Votes	NAT Votes	MIN Votes	OTH Votes	Total Votes
Dudley	Coseley East	9,607	Wolverhampton South and Coseley	2,230	2,579	56	256	94	0	0	0	5,215
Wolverhampton	Bilston East	9,442	Wolverhampton South and Coseley	1,941	3,326	27	267	37	0	0	0	5,598
Wolverhampton	Bilston North	8,649	Wolverhampton South and Coseley	1,840	2,659	41	228	81	0	0	0	4,849
Wolverhampton	Blakenhall	7,892	Wolverhampton West	1,374	3,327	29	163	27	0	0	0	4,920
Wolverhampton	East Park	8,550	Wolverhampton South and Coseley	1,780	3,013	52	239	102	0	0	0	5,186
Wolverhampton	Ettingshall	8,915	Wolverhampton South and Coseley	1,550	3,691	94	248	38	0	0	0	5,621
Wolverhampton	Spring Vale	8,578	Wolverhampton South and Coseley	1,908	2,541	149	274	40	0	0	0	4,912
	Total	61,633		12,623	21,136	448	1,675	419	0	0	0	36,301

The full details of these calculations are given on the Wolverhampton South East seat details page. Click on "Show workings".

New seat: Wolverhampton South and Coseley

District	Ward	Electorate 2017	Old Seat	CON Votes	LAB Votes	LIB Votes	UKIP Votes	Green Votes	NAT Votes	MIN Votes	OTH Votes	Total Votes
New seat: Wolverhampton South and Coseley
Dudley	Coseley East	10,049	Wolverhampton South East	2,230	2,579	56	256	94	0	0	0	5,215
Dudley	Sedgley	9,167	Dudley North	3,419	1,891	78	323	39	0	0	0	5,750
Dudley	Upper Gornal and Woodsetton	10,053	Dudley North	3,073	2,755	73	363	41	0	0	0	6,305
Wolverhampton	Bilston East	10,786	Wolverhampton South East	1,941	3,326	27	267	37	0	0	0	5,598
Wolverhampton	Bilston North	9,343	Wolverhampton South East	1,840	2,659	41	228	81	0	0	0	4,849
Wolverhampton	East Park	9,995	Wolverhampton South East	1,780	3,013	52	239	102	0	0	0	5,186
Wolverhampton	Ettingshall	10,831	Wolverhampton South East	1,550	3,691	94	248	38	0	0	0	5,621
Wolverhampton	Spring Vale	9,466	Wolverhampton South East	1,908	2,541	149	274	40	0	0	0	4,912
	Total	79,690		17,741	22,455	570	2,198	472	0	0	0	43,436

And these are the implied results for 2017 for the new seat of Wolverhampton South and Coseley. 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:	Pat McFadden (LAB)
County/Area:	Black Country (West Midlands)
Electorate:	79,690
Turnout:	54.5%

Wolverhampton South and Coseley: New Boundaries 2018 Calculation

Wolverhampton South and Coseley: Overview

Introduction