Brighton Kemptown and Seahaven: New Boundaries 2018 Calculation

Brighton Kemptown and Seahaven: Overview

 Projection: CON seat 

Implied MP at 2017: Unknown (changed seat)  (CON)
County/Area: East Sussex (South East)
Electorate: 76,167
Turnout: 77.9%

 Implied 2017 VotesImplied 2017 Share
CON26,32744.4%
LAB23,73940.0%
LIB9,15015.4%
OTH1430.2%
CON Majority2,5884.4%

See overview of other seats in South East.

Brighton Kemptown and Seahaven : Political and Demographic indicators

The table below shows some political and demographic numerical indicators for the new Brighton Kemptown and Seahaven constituency, the 'South East' area and nation.

The political measures include the Left/Right and International/National axes (what does this mean).

The demographic measures are from the 2011 Census and include categories relating to national identity, economic activity, health and education. These categories are those which have the most relevance to political attitudes.

IndicatorSeatSouth EastAll GB
Party WinnerCONCONCON
Economic Position4° Left4° Right
National Position3° Int3° Nat1° Int
EU Leave %50%52%52%
British Identity27%29%29%
Good Health47%49%48%
UK Born95%88%88%
Good Education41%43%39%
Good Job55%56%51%
High SEC56%57%51%
Average Age50.649.248.5
ABC1 Class57%60%53%

Brighton Kemptown and Seahaven ranks #386 for "Leave", #410 for "Right" and #416 for "National" out of 600 new seats.

Indicators: Legend and Descriptions

Indicators : Legend and Descriptions

The colour scheme used in the table above is explained in the legend table below. The eight census indicators (British Identity, Good Health, UK Born, Good Education, Good Job, High SEC, Average Age and AB1 Class) all use the same 'Census' colour scheme indicating whether the area's level is above or below the national average.

TopicCat 1Cat 2Cat 3Cat 4Cat 5
Economic PositionVery LeftLeftCentristRightVery Right
National PositionVery IntInternationalCentristNationalVery Nat
EU Leave %Very RemainRemainBalancedLeaveVery Leave
CensusVery LowLowMediumHighVery High

Indicator definitions are given in terms of political data definitions or census categories:

IndicatorCensus
Question
Definition / Included Census Categories
Party WinnerArea party winner : actual election result or projected by Electoral Calculus
Economic PositionEconomic position between 100° Left and 100° Right, estimated by Electoral Calculus from political and demographic data.
National PositionNational position between 100° International and 100° National, estimated by Electoral Calculus from political and demographic data.
EU Leave %EU Referendum vote share for 'Leave' : actual result or estimate
British IdentityNational Identity (KS202)Those answering British, British-Other, or Scottish-British
Good HealthHealth (KS301)Those answering 'Very Good Health'
UK BornCountry of Birth (QS203)Those answering England, Northern Ireland, Scotland, Wales, GB Other, or UK Other
Good EducationHighest level of Qualification (QS501)Level 3 (A-level equivalent) or Level 4+ (degree equivalent)
Good JobOccupation (QS606)Occupation codes 1xx to 4xx (Managers, Professionals, Associates, and office workers)
High SECNS-SeC of Household Reference Person (QS609)National Statistics Socio-economic Classification from 1 to 4 (higher managers and professionals, lower managers and professionals, intermediate occupations, small employers and self-employed).
Average AgeAge (QS103)Average age of adults (18 years and above)
ABC1 ClassApproximated Social Grade (QS611)Approximated social grades A, B and C1

Brighton Kemptown and Seahaven: Map

Boundary Lines courtesy of Ordnance Survey OpenData © Crown copyright 2015

Introduction

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

List of old seats forming part of Brighton Kemptown and Seahaven

The old seat(s) needed are:

Old seat: Brighton Kemptown

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

Old seat: Brighton KemptownTransfer-adjusted Results
DistrictWardElectorate
2017
New SeatCON
Votes
LAB
Votes
LIB
Votes
UKIP
Votes
Green
Votes
NAT
Votes
MIN
Votes
OTH
Votes
Total
Votes
Brighton and HoveEast Brighton10,425Brighton Kemptown and Seahaven2,0725,2931560000357,556
Brighton and HoveMoulsecoomb and Bevendean12,933Brighton Pavilion2,3896,818980000689,373
Brighton and HoveQueen's Park11,194Brighton Kemptown and Seahaven1,9495,7473760000408,112
Brighton and HoveRottingdean Coastal10,127Brighton Kemptown and Seahaven3,9853,0802600000157,340
Brighton and HoveWoodingdean7,260Brighton Kemptown and Seahaven2,6692,3821980000135,262
LewesEast Saltdean and Telscombe Cliffs5,422Brighton Kemptown and Seahaven2,0151,793118000043,930
LewesPeacehaven East3,636Brighton Kemptown and Seahaven1,2301,32577000052,637
LewesPeacehaven North3,514Brighton Kemptown and Seahaven1,2801,174720000202,546
LewesPeacehaven West3,383Brighton Kemptown and Seahaven1,2471,0931010000112,452
 Total67,894 18,83628,7051,456000021149,208

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

Old seat: Lewes

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

Old seat: LewesTransfer-adjusted Results
DistrictWardElectorate
2017
New SeatCON
Votes
LAB
Votes
LIB
Votes
UKIP
Votes
Green
Votes
NAT
Votes
MIN
Votes
OTH
Votes
Total
Votes
LewesBarcombe and Hamsey1,712Lewes and Uckfield684109515000001,308
LewesChailey and Wivelsfield4,113Lewes and Uckfield1,982991,060000003,141
LewesDitchling and Westmeston1,923Lewes and Uckfield968153348000001,469
LewesKingston1,679Lewes and Uckfield624100558000001,282
LewesLewes Bridge3,813Lewes and Uckfield1,0036311,278000002,912
LewesLewes Castle3,906Lewes and Uckfield9577511,274000002,982
LewesLewes Priory6,212Lewes and Uckfield1,8689581,920000004,746
LewesNewhaven Denton and Meeching6,596Brighton Kemptown and Seahaven2,1558382,046000005,039
LewesNewhaven Valley3,241Lewes and Uckfield1,0243251,126000002,475
LewesNewick1,934Lewes and Uckfield95437486000001,477
LewesOuse Valley and Ringmer5,182Lewes and Uckfield1,8983781,682000003,958
LewesPlumpton, Streat, East Chiltington and St John (Without)1,839Lewes and Uckfield72389593000001,405
LewesSeaford Central3,897Brighton Kemptown and Seahaven1,4542871,235000002,976
LewesSeaford East3,789Brighton Kemptown and Seahaven1,5731951,126000002,894
LewesSeaford North4,195Brighton Kemptown and Seahaven1,5463581,300000003,204
LewesSeaford South3,391Brighton Kemptown and Seahaven1,457801,053000002,590
LewesSeaford West3,693Brighton Kemptown and Seahaven1,695941,032000002,821
WealdenAlfriston1,852Lewes and Uckfield84530539000001,414
WealdenEast Dean1,821Lewes and Uckfield90833450000001,391
WealdenPolegate North4,197Lewes and Uckfield1,6833651,157000003,205
WealdenPolegate South1,963Lewes and Uckfield821147533000001,501
 Total70,948 26,8226,05721,3110000054,190

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

New seat: Brighton Kemptown and Seahaven

The new seat of Brighton Kemptown and Seahaven is made up of the following wards, with the transfer-adjusted votes shown.

New seat: Brighton Kemptown and Seahaven
DistrictWardElectorate
2017
Old Seat CON
Votes
LAB
Votes
LIB
Votes
UKIP
Votes
Green
Votes
NAT
Votes
MIN
Votes
OTH
Votes
Total
Votes
Brighton and HoveEast Brighton9,318Brighton Kemptown2,0725,2931560000357,556
Brighton and HoveQueen's Park10,037Brighton Kemptown1,9495,7473760000408,112
Brighton and HoveRottingdean Coastal10,224Brighton Kemptown3,9853,0802600000157,340
Brighton and HoveWoodingdean7,216Brighton Kemptown2,6692,3821980000135,262
LewesEast Saltdean and Telscombe Cliffs5,275Brighton Kemptown2,0151,793118000043,930
LewesNewhaven Denton and Meeching5,532Lewes2,1558382,046000005,039
LewesPeacehaven East3,825Brighton Kemptown1,2301,32577000052,637
LewesPeacehaven North3,148Brighton Kemptown1,2801,174720000202,546
LewesPeacehaven West3,164Brighton Kemptown1,2471,0931010000112,452
LewesSeaford Central3,500Lewes1,4542871,235000002,976
LewesSeaford East3,792Lewes1,5731951,126000002,894
LewesSeaford North3,913Lewes1,5463581,300000003,204
LewesSeaford South3,480Lewes1,457801,053000002,590
LewesSeaford West3,743Lewes1,695941,032000002,821
 Total76,167 26,32723,7399,150000014359,359

And these are the implied results for 2017 for the new seat of Brighton Kemptown and Seahaven.


© 2017 Martin Baxter
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