Vale of Glamorgan East: New Boundaries 2018 Calculation

Vale of Glamorgan East: Overview

 Projection: LAB seat 

Implied MP at 2017: Unknown (changed seat)  (LAB)
County/Area: South Glamorgan (Wales)
Electorate: 76,984
Turnout: 72.7%

 Implied 2017 VotesImplied 2017 Share
LAB25,76346.0%
CON25,04944.8%
Plaid2,4674.4%
LIB1,1092.0%
UKIP1,0431.9%
Green2880.5%
OTH2450.4%
LAB Majority7141.3%

See overview of other seats in Wales.

Vale of Glamorgan East : Political and Demographic indicators

The table below shows some political and demographic numerical indicators for the new Vale of Glamorgan East constituency, the 'Wales' 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.

IndicatorSeatWalesAll GB
Party WinnerLABLABCON
Economic Position2° Left10° Left
National Position4° Int3° Int1° Int
EU Leave %49%53%52%
British Identity29%26%29%
Good Health51%47%48%
UK Born90%95%88%
Good Education47%36%39%
Good Job61%46%51%
High SEC63%46%51%
Average Age49.449.648.5
ABC1 Class64%47%53%

Vale of Glamorgan East ranks #406 for "Leave", #373 for "Right" and #430 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

Vale of Glamorgan East: 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 Vale of Glamorgan East 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 Vale of Glamorgan East

The old seat(s) needed are:

Old seat: Cardiff South and Penarth

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

Old seat: Cardiff South and PenarthTransfer-adjusted Results
DistrictWardElectorate
2017
New SeatCON
Votes
LAB
Votes
LIB
Votes
UKIP
Votes
Green
Votes
Plaid
Votes
MIN
Votes
OTH
Votes
Total
Votes
CardiffButetown7,213Cardiff South and East1,2432,78933187962270114,784
CardiffGrangetown13,794Cardiff West2,4035,702163671336560249,148
CardiffLlanrumney7,879Cardiff South and East1,0093,7144015115291055,225
CardiffPontprennau / Old St Mellons117 373730120080
CardiffRumney6,236Cardiff South and East1,3972,40221101121700344,137
CardiffSplott9,446Cardiff South and East1,3144,26629866892020306,265
CardiffTrowbridge11,504Cardiff South and East2,0434,99113610390257097,629
Vale of GlamorganCornerswell3,760Vale of Glamorgan East9081,327100366113042,494
Vale of GlamorganLlandough1,405Vale of Glamorgan East32054932402502932
Vale of GlamorganPlymouth4,166Vale of Glamorgan East1,5551,0468710062022,762
Vale of GlamorganSt Augustine's4,645Vale of Glamorgan East1,2651,512122128779033,080
Vale of GlamorganStanwell3,167Vale of Glamorgan East7471,2086320357012,099
Vale of GlamorganSully3,167Vale of Glamorgan East1,079639332851200442,101
 Total76,499 15,32030,1821,4299425332,161016950,736

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

Old seat: Vale of Glamorgan

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

Old seat: Vale of GlamorganTransfer-adjusted Results
DistrictWardElectorate
2017
New SeatCON
Votes
LAB
Votes
LIB
Votes
UKIP
Votes
Green
Votes
Plaid
Votes
MIN
Votes
OTH
Votes
Total
Votes
Vale of GlamorganBaruc4,852Vale of Glamorgan East1,7081,3816870292450233,524
Vale of GlamorganButtrills4,930Vale of Glamorgan East1,0532,0755169272940133,582
Vale of GlamorganCadoc7,581Vale of Glamorgan East1,9653,0684675233080215,506
Vale of GlamorganCastleland3,637Vale of Glamorgan East7191,605326319202032,643
Vale of GlamorganCourt3,636Vale of Glamorgan East7961,542446571660212,641
Vale of GlamorganCowbridge4,685Vale of Glamorgan East2,2279961038460053,403
Vale of GlamorganDinas Powys5,937Vale of Glamorgan East2,3361,40714051313370104,312
Vale of GlamorganDyfan3,879Vale of Glamorgan East1,1911,42412573124062,817
Vale of GlamorganGibbonsdown4,379Vale of Glamorgan East9301,9454288171370223,181
Vale of GlamorganIlltyd6,094Vale of Glamorgan East2,0822,0386752201400274,426
Vale of GlamorganLlandow / Ewenny2,018Bridgend and Vale of Glamorgan West956417247553031,465
Vale of GlamorganLlantwit Major8,011Bridgend and Vale of Glamorgan West3,1881,96927317760520995,818
Vale of GlamorganPeterston-super-Ely1,702Vale of Glamorgan East832345180436011,236
Vale of GlamorganRhoose5,250Vale of Glamorgan East2,3551,24144787540353,814
Vale of GlamorganSt Athan3,407Bridgend and Vale of Glamorgan West1,3621,003236171082,474
Vale of GlamorganSt Bride's Major2,018Bridgend and Vale of Glamorgan West8214382921628051,465
Vale of GlamorganWenvoe1,943Vale of Glamorgan East9814155008021,411
 Total73,959 25,50223,3091,0218684192,295030453,718

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

New seat: Vale of Glamorgan East

The new seat of Vale of Glamorgan East is made up of the following wards, with the transfer-adjusted votes shown.

New seat: Vale of Glamorgan East
DistrictWardElectorate
2017
Old Seat CON
Votes
LAB
Votes
LIB
Votes
UKIP
Votes
Green
Votes
Plaid
Votes
MIN
Votes
OTH
Votes
Total
Votes
Vale of GlamorganBaruc4,636Vale of Glamorgan1,7081,3816870292450233,524
Vale of GlamorganButtrills4,175Vale of Glamorgan1,0532,0755169272940133,582
Vale of GlamorganCadoc6,842Vale of Glamorgan1,9653,0684675233080215,506
Vale of GlamorganCastleland3,096Vale of Glamorgan7191,605326319202032,643
Vale of GlamorganCornerswell3,885Cardiff South and Penarth9081,327100366113042,494
Vale of GlamorganCourt3,031Vale of Glamorgan7961,542446571660212,641
Vale of GlamorganCowbridge4,997Vale of Glamorgan2,2279961038460053,403
Vale of GlamorganDinas Powys6,139Vale of Glamorgan2,3361,40714051313370104,312
Vale of GlamorganDyfan3,983Vale of Glamorgan1,1911,42412573124062,817
Vale of GlamorganGibbonsdown3,646Vale of Glamorgan9301,9454288171370223,181
Vale of GlamorganIlltyd5,951Vale of Glamorgan2,0822,0386752201400274,426
Vale of GlamorganLlandough1,454Cardiff South and Penarth32054932402502932
Vale of GlamorganPeterston-super-Ely1,828Vale of Glamorgan832345180436011,236
Vale of GlamorganPlymouth4,419Cardiff South and Penarth1,5551,0468710062022,762
Vale of GlamorganRhoose5,158Vale of Glamorgan2,3551,24144787540353,814
Vale of GlamorganSt Augustine's4,913Cardiff South and Penarth1,2651,512122128779033,080
Vale of GlamorganStanwell3,178Cardiff South and Penarth7471,2086320357012,099
Vale of GlamorganSully3,531Cardiff South and Penarth1,079639332851200442,101
Vale of GlamorganWenvoe2,122Vale of Glamorgan9814155008021,411
 Total76,984 25,04925,7631,1091,0432882,467024555,964

And these are the implied results for 2017 for the new seat of Vale of Glamorgan East.


© 2017 Martin Baxter
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