New Seat Details - Norwich South

This page shows the detail of the calculations performed to estimate the general election result for 2017 had the new boundaries for Norwich South 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	29,863	56.5%
CON	18,043	34.2%
LIB	3,470	6.6%
Green	1,436	2.7%
LAB Majority	11,820	22.4%

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.

Norwich South: Map

List of old seats forming part of Norwich South

Old seat: Norfolk South

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

Old seat: Norfolk South				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
South Norfolk	Beck Vale	1,818	Norfolk South	839	373	98	0	61	0	0	0	1,371
South Norfolk	Bressingham and Burston	2,228	Norfolk South	1,128	480	64	0	84	0	0	0	1,756
South Norfolk	Brooke	2,085	Norfolk South	1,085	427	121	0	26	0	0	0	1,659
South Norfolk	Bunwell	2,166	Norfolk South	1,076	517	96	0	24	0	0	0	1,713
South Norfolk	Chedgrave and Thurton	2,108	Norfolk South	1,035	527	116	0	32	0	0	0	1,710
South Norfolk	Cringleford	4,448	Norwich South	2,017	820	282	0	56	0	0	0	3,175
South Norfolk	Dickleburgh	2,169	Norfolk South	1,150	441	89	0	73	0	0	0	1,753
South Norfolk	Diss	5,757	Norfolk South	2,432	1,668	411	0	195	0	0	0	4,706
South Norfolk	Ditchingham and Broome	1,945	Norfolk South	756	465	211	0	26	0	0	0	1,458
South Norfolk	Earsham	1,986	Norfolk South	820	492	191	0	23	0	0	0	1,526
South Norfolk	Easton	2,039	Norfolk South	1,112	433	126	0	29	0	0	0	1,700
South Norfolk	Forncett	2,175	Norfolk South	995	454	205	0	27	0	0	0	1,681
South Norfolk	Gillingham	2,261	Norfolk South	1,044	568	145	0	30	0	0	0	1,787
South Norfolk	Harleston	3,712	Norfolk South	1,631	992	217	0	47	0	0	0	2,887
South Norfolk	Hempnall	2,065	Norfolk South	1,044	459	65	0	24	0	0	0	1,592
South Norfolk	Hethersett	4,470	Norfolk South	2,057	1,139	271	0	60	0	0	0	3,527
South Norfolk	Loddon	2,182	Norfolk South	929	542	125	0	31	0	0	0	1,627
South Norfolk	Mulbarton	4,088	Norfolk South	1,928	948	217	0	135	0	0	0	3,228
South Norfolk	Newton Flotman	2,081	Norfolk South	962	538	128	0	27	0	0	0	1,655
South Norfolk	Old Costessey	6,098	Norwich South	1,989	1,811	577	0	77	0	0	0	4,454
South Norfolk	Poringland with the Framinghams	4,044	Norfolk South	1,923	782	236	0	49	0	0	0	2,990
South Norfolk	Rockland	2,308	Norfolk South	1,048	537	151	0	28	0	0	0	1,764
South Norfolk	Roydon	1,837	Norfolk South	908	485	106	0	23	0	0	0	1,522
South Norfolk	Scole	1,893	Norfolk South	950	363	85	0	62	0	0	0	1,460
South Norfolk	Stoke Holy Cross	2,226	Norfolk South	900	541	247	0	95	0	0	0	1,783
South Norfolk	Stratton	4,240	Norfolk South	1,895	1,147	232	0	161	0	0	0	3,435
South Norfolk	Tasburgh	1,907	Norfolk South	930	417	124	0	24	0	0	0	1,495
South Norfolk	Thurlton	2,216	Great Yarmouth	995	538	139	0	27	0	0	0	1,699
	Total	78,552		35,578	18,904	5,075	0	1,556	0	0	0	61,113

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

Old seat: Norwich South

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

Old seat: Norwich South				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
Norwich	Bowthorpe	7,872	Norwich South	1,933	3,857	261	0	157	0	0	0	6,208
Norwich	Eaton	7,167	Norwich South	1,923	2,292	325	0	126	0	0	0	4,666
Norwich	Lakenham	6,709	Norwich South	1,322	3,192	328	0	136	0	0	0	4,978
Norwich	Mancroft	7,466	Norwich South	1,412	3,294	248	0	164	0	0	0	5,118
Norwich	Nelson	6,650	Norwich South	1,344	3,082	353	0	196	0	0	0	4,975
Norwich	Thorpe Hamlet	8,199	Norwich South	1,911	3,183	295	0	160	0	0	0	5,549
Norwich	Town Close	7,968	Norwich South	1,810	3,165	364	0	177	0	0	0	5,516
Norwich	University	5,101	Norwich South	1,330	3,659	252	0	154	0	0	0	5,395
Norwich	Wensum	7,705	Norwich North	1,678	4,079	230	0	189	0	0	0	6,176
South Norfolk	New Costessey	4,126	Norwich South	1,052	1,508	185	0	33	0	0	0	2,778
	Total	68,963		15,715	31,311	2,841	0	1,492	0	0	0	51,359

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

New seat: Norwich South

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: Norwich South
Norwich	Bowthorpe	8,966	Norwich South	1,933	3,857	261	0	157	0	0	0	6,208
Norwich	Eaton	6,739	Norwich South	1,923	2,292	325	0	126	0	0	0	4,666
Norwich	Lakenham	7,191	Norwich South	1,322	3,192	328	0	136	0	0	0	4,978
Norwich	Mancroft	7,392	Norwich South	1,412	3,294	248	0	164	0	0	0	5,118
Norwich	Nelson	7,186	Norwich South	1,344	3,082	353	0	196	0	0	0	4,975
Norwich	Thorpe Hamlet	8,016	Norwich South	1,911	3,183	295	0	160	0	0	0	5,549
Norwich	Town Close	7,968	Norwich South	1,810	3,165	364	0	177	0	0	0	5,516
Norwich	University	7,791	Norwich South	1,330	3,659	252	0	154	0	0	0	5,395
South Norfolk	Cringleford	4,316	Norfolk South	2,017	820	282	0	56	0	0	0	3,175
South Norfolk	New Costessey	4,013	Norwich South	1,052	1,508	185	0	33	0	0	0	2,778
South Norfolk	Old Costessey	6,053	Norfolk South	1,989	1,811	577	0	77	0	0	0	4,454
	Total	75,631		18,043	29,863	3,470	0	1,436	0	0	0	52,812

And these are the implied results for 2017 for the new seat of Norwich South. 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:	Clive Lewis (LAB)
County/Area:	Norfolk (Anglia)
Electorate:	75,631
Turnout:	69.8%

Norwich South: New Boundaries 2018 Calculation

Norwich South: Overview

Introduction