New Seat Details - Feltham and Hounslow

This page shows the detail of the calculations performed to estimate the general election result for 2017 had the new boundaries for Feltham and Hounslow 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	31,285	60.2%
CON	17,123	33.0%
LIB	1,927	3.7%
UKIP	1,052	2.0%
Green	569	1.1%
LAB Majority	14,162	27.3%

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.

Feltham and Hounslow: Map

List of old seats forming part of Feltham and Hounslow

Old seat: Brentford and Isleworth

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

Old seat: Brentford and Isleworth				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
Hounslow	Brentford	9,080	Isleworth, Brentford and Chiswick	1,936	4,478	467	0	0	0	0	0	6,881
Hounslow	Chiswick Homefields	7,051	Isleworth, Brentford and Chiswick	2,717	2,412	290	0	0	0	0	0	5,419
Hounslow	Chiswick Riverside	7,590	Isleworth, Brentford and Chiswick	2,805	2,422	309	0	0	0	0	0	5,536
Hounslow	Hounslow Central	8,939	Feltham and Hounslow	2,119	4,813	333	0	0	0	0	0	7,265
Hounslow	Hounslow Heath	8,501	Feltham and Hounslow	1,920	4,802	336	0	0	0	0	0	7,058
Hounslow	Hounslow South	7,674	Feltham and Hounslow	2,232	3,049	195	0	0	0	0	0	5,476
Hounslow	Isleworth	7,540	Isleworth, Brentford and Chiswick	1,780	3,773	217	0	0	0	0	0	5,770
Hounslow	Osterley and Spring Grove	8,361	Isleworth, Brentford and Chiswick	2,797	3,155	273	0	0	0	0	0	6,225
Hounslow	Syon	8,723	Isleworth, Brentford and Chiswick	2,082	4,119	298	0	0	0	0	0	6,499
Hounslow	Turnham Green	6,968	Isleworth, Brentford and Chiswick	2,795	2,341	364	0	0	0	0	0	5,500
	Total	80,427		23,183	35,364	3,082	0	0	0	0	0	61,629

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

Old seat: Feltham and Heston

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

Old seat: Feltham and Heston				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
Hounslow	Bedfont	8,200	Feltham and Hounslow	2,038	2,871	244	104	114	0	0	0	5,371
Hounslow	Cranford	7,651	Southall and Heston	1,568	3,359	95	139	45	0	0	0	5,206
Hounslow	Feltham North	7,198	Feltham and Hounslow	1,737	2,672	172	198	113	0	0	0	4,892
Hounslow	Feltham West	9,208	Feltham and Hounslow	2,224	3,897	140	253	59	0	0	0	6,573
Hounslow	Hanworth	7,601	Feltham and Hounslow	1,556	3,067	187	203	126	0	0	0	5,139
Hounslow	Hanworth Park	7,537	Feltham and Hounslow	1,895	2,496	163	214	53	0	0	0	4,821
Hounslow	Heston Central	7,751	Southall and Heston	1,620	3,330	77	121	47	0	0	0	5,195
Hounslow	Heston East	8,091	Southall and Heston	1,506	3,510	64	72	108	0	0	0	5,260
Hounslow	Heston West	8,026	Southall and Heston	1,312	3,642	87	128	40	0	0	0	5,209
Hounslow	Hounslow West	7,820	Feltham and Hounslow	1,402	3,618	157	80	104	0	0	0	5,361
	Total	79,083		16,858	32,462	1,386	1,512	809	0	0	0	53,027

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

New seat: Feltham and Hounslow

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: Feltham and Hounslow
Hounslow	Bedfont	8,276	Feltham and Heston	2,038	2,871	244	104	114	0	0	0	5,371
Hounslow	Feltham North	7,538	Feltham and Heston	1,737	2,672	172	198	113	0	0	0	4,892
Hounslow	Feltham West	10,127	Feltham and Heston	2,224	3,897	140	253	59	0	0	0	6,573
Hounslow	Hanworth	7,919	Feltham and Heston	1,556	3,067	187	203	126	0	0	0	5,139
Hounslow	Hanworth Park	7,428	Feltham and Heston	1,895	2,496	163	214	53	0	0	0	4,821
Hounslow	Hounslow Central	10,037	Brentford and Isleworth	2,119	4,813	333	0	0	0	0	0	7,265
Hounslow	Hounslow Heath	9,751	Brentford and Isleworth	1,920	4,802	336	0	0	0	0	0	7,058
Hounslow	Hounslow South	7,567	Brentford and Isleworth	2,232	3,049	195	0	0	0	0	0	5,476
Hounslow	Hounslow West	8,260	Feltham and Heston	1,402	3,618	157	80	104	0	0	0	5,361
	Total	76,903		17,123	31,285	1,927	1,052	569	0	0	0	51,956

And these are the implied results for 2017 for the new seat of Feltham and Hounslow. 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:	Seema Malhotra (LAB)
County/Area:	Hounslow (London)
Electorate:	76,903
Turnout:	67.6%

Feltham and Hounslow: New Boundaries 2018 Calculation

Feltham and Hounslow: Overview

Introduction