New Seat Details - Bermondsey and Old Southwark

This page shows the detail of the calculations performed to estimate the general election result for 2017 had the new boundaries for Bermondsey and Old Southwark 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	31,255	54.6%
LIB	16,744	29.3%
CON	7,616	13.3%
UKIP	772	1.3%
Green	701	1.2%
OTH	133	0.2%
LAB Majority	14,511	25.4%

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.

Bermondsey and Old Southwark: Map

List of old seats forming part of Bermondsey and Old Southwark

Old seat: Bermondsey and Old Southwark

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

Old seat: Bermondsey and Old Southwark				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
Southwark	Cathedrals	9,551	Bermondsey and Old Southwark	912	3,291	2,529	95	92	0	0	17	6,936
Southwark	Chaucer	9,361	Bermondsey and Old Southwark	715	3,915	2,225	50	80	0	0	14	6,999
Southwark	East Walworth	7,317	Bermondsey and Old Southwark	506	3,475	1,236	48	53	0	0	16	5,334
Southwark	Grange	10,308	Bermondsey and Old Southwark	1,057	3,536	2,244	120	79	0	0	11	7,047
Southwark	Newington	9,433	Camberwell and Peckham	538	4,155	1,690	67	74	0	0	25	6,549
Southwark	Riverside	9,177	Bermondsey and Old Southwark	1,122	2,896	2,447	105	79	0	0	10	6,659
Southwark	Rotherhithe	8,634	Bermondsey and Old Southwark	810	3,527	1,801	116	62	0	0	9	6,325
Southwark	South Bermondsey	8,148	Bermondsey and Old Southwark	573	3,623	2,041	131	53	0	0	10	6,431
Southwark	Surrey Docks	8,245	Bermondsey and Old Southwark	1,348	2,745	1,976	107	67	0	0	2	6,245
	Total	80,174		7,581	31,163	18,189	839	639	0	0	114	58,525

The full details of these calculations are given on the Bermondsey and Old Southwark seat details page. Click on "Show workings".

Old seat: Camberwell and Peckham

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

Old seat: Camberwell and Peckham				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
Southwark	Brunswick Park	8,656	Camberwell and Peckham	755	4,818	427	0	188	0	0	39	6,227
Southwark	Camberwell Green	9,134	Camberwell and Peckham	716	5,549	338	0	191	0	0	48	6,842
Southwark	Faraday	6,882	Bermondsey and Old Southwark	573	4,247	245	0	136	0	0	44	5,245
Southwark	Livesey	8,669	Camberwell and Peckham	694	5,288	356	0	161	0	0	44	6,543
Southwark	Nunhead	9,269	Camberwell and Peckham	756	5,040	355	0	182	0	0	46	6,379
Southwark	Peckham	9,281	Camberwell and Peckham	653	5,692	284	0	179	0	0	44	6,852
Southwark	Peckham Rye	9,463	Dulwich and Sydenham	1,194	4,394	482	0	194	0	0	22	6,286
Southwark	South Camberwell	8,471	Camberwell and Peckham	921	4,278	452	0	181	0	0	34	5,866
Southwark	The Lane	10,550	Camberwell and Peckham	1,088	5,359	473	0	213	0	0	37	7,170
	Total	80,375		7,350	44,665	3,412	0	1,625	0	0	358	57,410

The full details of these calculations are given on the Camberwell and Peckham seat details page. Click on "Show workings".

New seat: Bermondsey and Old Southwark

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: Bermondsey and Old Southwark
Southwark	Cathedrals	10,339	Bermondsey and Old Southwark	912	3,291	2,529	95	92	0	0	17	6,936
Southwark	Chaucer	10,432	Bermondsey and Old Southwark	715	3,915	2,225	50	80	0	0	14	6,999
Southwark	East Walworth	7,952	Bermondsey and Old Southwark	506	3,475	1,236	48	53	0	0	16	5,334
Southwark	Faraday	7,818	Camberwell and Peckham	573	4,247	245	0	136	0	0	44	5,245
Southwark	Grange	10,504	Bermondsey and Old Southwark	1,057	3,536	2,244	120	79	0	0	11	7,047
Southwark	Riverside	9,925	Bermondsey and Old Southwark	1,122	2,896	2,447	105	79	0	0	10	6,659
Southwark	Rotherhithe	9,426	Bermondsey and Old Southwark	810	3,527	1,801	116	62	0	0	9	6,325
Southwark	South Bermondsey	9,582	Bermondsey and Old Southwark	573	3,623	2,041	131	53	0	0	10	6,431
Southwark	Surrey Docks	9,307	Bermondsey and Old Southwark	1,348	2,745	1,976	107	67	0	0	2	6,245
	Total	85,285		7,616	31,255	16,744	772	701	0	0	133	57,221

And these are the implied results for 2017 for the new seat of Bermondsey and Old Southwark. 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:	Neil Coyle (LAB)
County/Area:	Southwark (London)
Electorate:	85,285
Turnout:	67.1%

Bermondsey and Old Southwark: New Boundaries 2018 Calculation

Bermondsey and Old Southwark: Overview

Introduction