Sittingbourne and Sheppey: New Boundaries 2018 Calculation

Sittingbourne and Sheppey: Overview

Projection: CON seat

Implied MP at 2017:Gordon Henderson  (CON)
County/Area:Kent (South East)
Electorate:81,713
Turnout:62.9%

PartyImplied 2017 VotesImplied 2017 Share
CON30,91360.1%
LAB15,70230.6%
MIN2,1324.1%
LIB1,3942.7%
OTH6971.4%
Green5571.1%
CON Majority15,21129.6%

See overview of other seats in South East.



Introduction

This page shows the detail of the calculations performed to estimate the general election result for 2017 had the new boundaries for Sittingbourne and Sheppey 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.

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.

More details of the calculation formulas are available.

Sittingbourne and Sheppey: Map

Boundary Lines courtesy of Ordnance Survey OpenData © Crown copyright 2015, Map © OpenStreetMap contributors

List of old seats forming part of Sittingbourne and Sheppey

The old seat(s) needed are:

Old seat: Sittingbourne and Sheppey

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

Old seat: Sittingbourne and SheppeyTransfer-adjusted Results
DistrictWardElectorate
2017
New SeatCON
Votes
LAB
Votes
LIB
Votes
UKIP
Votes
Green
Votes
NAT
Votes
MIN
Votes
OTH
Votes
Total
Votes
SwaleBobbing, Iwade and Lower Halstow3,895Sittingbourne and Sheppey1,71845333020079262,329
SwaleBorden and Grove Park4,423Sittingbourne and Sheppey2,042554620320103342,827
SwaleChalkwell1,914Sittingbourne and Sheppey67760062020056181,433
SwaleHartlip, Newington and Upchurch4,403Sittingbourne and Sheppey2,07050133025093312,753
SwaleHomewood4,569Sittingbourne and Sheppey1,6251,0491500380101332,996
SwaleKemsley4,103Sittingbourne and Sheppey1,895899117033099333,076
SwaleMilton Regis4,107Sittingbourne and Sheppey1,3431,242143034096312,889
SwaleMinster Cliffs5,652Sittingbourne and Sheppey2,523676440330122403,438
SwaleMurston3,905Sittingbourne and Sheppey1,3941,1141640330104342,843
SwaleQueenborough and Halfway5,375Sittingbourne and Sheppey1,9591,274610370166543,551
SwaleRoman4,287Sittingbourne and Sheppey1,4631,34578035095313,047
SwaleSheerness6,927Sittingbourne and Sheppey2,5212,7041100610209685,673
SwaleSheppey Central5,815Sittingbourne and Sheppey2,223864600370206673,457
SwaleSheppey East3,734Sittingbourne and Sheppey1,912800500310179583,030
SwaleTeynham and Lynsted3,951Sittingbourne and Sheppey1,85053541030094312,581
SwaleThe Meads2,075Sittingbourne and Sheppey97535936015049161,450
SwaleWest Downs2,110Sittingbourne and Sheppey909200180120128421,309
SwaleWoodstock4,393Sittingbourne and Sheppey1,8145331320310153502,713
 Total75,638 30,91315,7021,394055702,13269751,395

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

New seat: Sittingbourne and Sheppey

The new seat of Sittingbourne and Sheppey is made up of the following wards, with the transfer-adjusted votes shown.

New seat: Sittingbourne and Sheppey
DistrictWardElectorate
2017
Old Seat CON
Votes
LAB
Votes
LIB
Votes
UKIP
Votes
Green
Votes
NAT
Votes
MIN
Votes
OTH
Votes
Total
Votes
SwaleBobbing, Iwade and Lower Halstow3,702Sittingbourne and Sheppey1,71845333020079262,329
SwaleBorden and Grove Park4,496Sittingbourne and Sheppey2,042554620320103342,827
SwaleChalkwell2,278Sittingbourne and Sheppey67760062020056181,433
SwaleHartlip, Newington and Upchurch4,376Sittingbourne and Sheppey2,07050133025093312,753
SwaleHomewood4,763Sittingbourne and Sheppey1,6251,0491500380101332,996
SwaleKemsley4,889Sittingbourne and Sheppey1,895899117033099333,076
SwaleMilton Regis4,592Sittingbourne and Sheppey1,3431,242143034096312,889
SwaleMinster Cliffs5,467Sittingbourne and Sheppey2,523676440330122403,438
SwaleMurston4,519Sittingbourne and Sheppey1,3941,1141640330104342,843
SwaleQueenborough and Halfway5,645Sittingbourne and Sheppey1,9591,274610370166543,551
SwaleRoman4,847Sittingbourne and Sheppey1,4631,34578035095313,047
SwaleSheerness9,022Sittingbourne and Sheppey2,5212,7041100610209685,673
SwaleSheppey Central5,496Sittingbourne and Sheppey2,223864600370206673,457
SwaleSheppey East4,819Sittingbourne and Sheppey1,912800500310179583,030
SwaleTeynham and Lynsted4,104Sittingbourne and Sheppey1,85053541030094312,581
SwaleThe Meads2,305Sittingbourne and Sheppey97535936015049161,450
SwaleWest Downs2,079Sittingbourne and Sheppey909200180120128421,309
SwaleWoodstock4,314Sittingbourne and Sheppey1,8145331320310153502,713
 Total81,713 30,91315,7021,394055702,13269751,395

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


© 2024 Electoral Calculus Ltd
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