Shrewsbury: New Boundaries 2018 Calculation

Shrewsbury: Overview

 Projection: CON seat 

Implied MP at 2017: Daniel Kawczynski  (CON)
County/Area: Shropshire (West Midlands)
Electorate: 81,495
Turnout: 73.6%

 Implied 2017 VotesImplied 2017 Share
CON30,15150.3%
LAB22,86038.1%
LIB4,5337.6%
UKIP1,3632.3%
Green1,0941.8%
CON Majority7,29112.2%

See overview of other seats in West Midlands.

Shrewsbury : Political and Demographic indicators

The table below shows some political and demographic numerical indicators for the new Shrewsbury constituency, the 'West Midlands' 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.

IndicatorSeatWest MidlandsAll GB
Party WinnerCONCONCON
Economic Position4° Right2° Right
National Position6° Nat9° Nat1° Int
EU Leave %53%59%52%
British Identity27%28%29%
Good Health47%45%48%
UK Born94%89%88%
Good Education42%35%39%
Good Job50%48%51%
High SEC53%46%51%
Average Age50.648.748.5
ABC1 Class53%49%53%

Shrewsbury ranks #306 for "Leave", #246 for "Right" and #223 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

Shrewsbury: 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 Shrewsbury 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 Shrewsbury

The old seat(s) needed are:

Old seat: Ludlow

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

Old seat: LudlowTransfer-adjusted Results
DistrictWardElectorate
2017
New SeatCON
Votes
LAB
Votes
LIB
Votes
UKIP
Votes
Green
Votes
NAT
Votes
MIN
Votes
OTH
Votes
Total
Votes
ShropshireAlveley and Claverley3,225Bridgnorth and The Wrekin1,7494481440260002,367
ShropshireBishop's Castle2,980Ludlow and Leominster1,24350532701140002,189
ShropshireBridgnorth East and Astley Abbotts5,303Bridgnorth and The Wrekin2,4289434640600003,895
ShropshireBridgnorth West and Tasley5,460Bridgnorth and The Wrekin2,5119854570580004,011
ShropshireBroseley3,713Bridgnorth and The Wrekin1,3131,2041730380002,728
ShropshireBrown Clee3,167Ludlow and Leominster1,7744141080300002,326
ShropshireChirbury and Worthen2,453Shrewsbury1,0784162810270001,802
ShropshireChurch Stretton and Craven Arms7,155Ludlow and Leominster3,2241,2886540890005,255
ShropshireClee3,695Ludlow and Leominster1,6856293650350002,714
ShropshireCleobury Mortimer5,775Ludlow and Leominster2,9939422360710004,242
ShropshireClun3,193Ludlow and Leominster1,36851534301190002,345
ShropshireCorvedale3,033Ludlow and Leominster1,773332960270002,228
ShropshireHighley2,890Ludlow and Leominster1,2306162450320002,123
ShropshireLudlow East3,307Ludlow and Leominster1,13085133401130002,428
ShropshireLudlow North2,940Ludlow and Leominster1,17655332601050002,160
ShropshireLudlow South3,333Ludlow and Leominster1,3316554190430002,448
ShropshireMuch Wenlock3,446Ludlow and Leominster1,6805412700400002,531
ShropshireWorfield2,967Bridgnorth and The Wrekin1,749311940250002,179
 Total68,035 31,43512,1485,33601,05200049,971

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

Old seat: Shrewsbury and Atcham

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

Old seat: Shrewsbury and AtchamTransfer-adjusted Results
DistrictWardElectorate
2017
New SeatCON
Votes
LAB
Votes
LIB
Votes
UKIP
Votes
Green
Votes
NAT
Votes
MIN
Votes
OTH
Votes
Total
Votes
ShropshireAbbey2,907Shrewsbury1,031629281981010002,140
ShropshireBagley3,565Shrewsbury1,228963277441130002,625
ShropshireBattlefield2,960Shrewsbury1,13887710038260002,179
ShropshireBayston Hill, Column and Sutton9,322Shrewsbury2,8933,312311259900006,865
ShropshireBelle Vue3,375Shrewsbury9071,35714136450002,486
ShropshireBowbrook3,115Shrewsbury1,28683210836320002,294
ShropshireBurnell3,514Shrewsbury1,75957619030330002,588
ShropshireCastlefields and Ditherington3,477Shrewsbury7921,55613142400002,561
ShropshireCopthorne3,181Shrewsbury1,39465017093340002,341
ShropshireHarlescott3,836Shrewsbury9661,64712848350002,824
ShropshireLongden3,174Shrewsbury1,296666240102330002,337
ShropshireLoton3,164Shrewsbury1,58953115529260002,330
ShropshireMeole3,335Shrewsbury1,25797115735350002,455
ShropshireRea Valley3,219Shrewsbury1,430677133100300002,370
ShropshireMonkmoor3,514Shrewsbury9521,42313743320002,587
ShropshirePorthill3,615Shrewsbury1,400751335401370002,663
ShropshireQuarry and Coton Hill3,153Shrewsbury1,15578629734490002,321
ShropshireRadbrook3,116Shrewsbury1,30069422936350002,294
ShropshireSevern Valley3,317Shrewsbury1,72755910227270002,442
ShropshireSundorne3,355Shrewsbury8371,44111940330002,470
ShropshireTern3,401Shrewsbury1,63862717632310002,504
ShropshireUnderdale3,427Shrewsbury1,098919335121500002,523
 Total79,042 29,07322,4444,2521,3631,06700058,199

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

New seat: Shrewsbury

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

New seat: Shrewsbury
DistrictWardElectorate
2017
Old Seat CON
Votes
LAB
Votes
LIB
Votes
UKIP
Votes
Green
Votes
NAT
Votes
MIN
Votes
OTH
Votes
Total
Votes
ShropshireAbbey2,907Shrewsbury and Atcham1,031629281981010002,140
ShropshireBagley3,565Shrewsbury and Atcham1,228963277441130002,625
ShropshireBattlefield2,960Shrewsbury and Atcham1,13887710038260002,179
ShropshireBayston Hill, Column and Sutton9,322Shrewsbury and Atcham2,8933,312311259900006,865
ShropshireBelle Vue3,375Shrewsbury and Atcham9071,35714136450002,486
ShropshireBowbrook3,115Shrewsbury and Atcham1,28683210836320002,294
ShropshireBurnell3,514Shrewsbury and Atcham1,75957619030330002,588
ShropshireCastlefields and Ditherington3,477Shrewsbury and Atcham7921,55613142400002,561
ShropshireChirbury and Worthen2,453Ludlow1,0784162810270001,802
ShropshireCopthorne3,181Shrewsbury and Atcham1,39465017093340002,341
ShropshireHarlescott3,836Shrewsbury and Atcham9661,64712848350002,824
ShropshireLongden3,174Shrewsbury and Atcham1,296666240102330002,337
ShropshireLoton3,164Shrewsbury and Atcham1,58953115529260002,330
ShropshireMeole3,335Shrewsbury and Atcham1,25797115735350002,455
ShropshireMonkmoor3,514Shrewsbury and Atcham9521,42313743320002,587
ShropshirePorthill3,615Shrewsbury and Atcham1,400751335401370002,663
ShropshireQuarry and Coton Hill3,153Shrewsbury and Atcham1,15578629734490002,321
ShropshireRadbrook3,116Shrewsbury and Atcham1,30069422936350002,294
ShropshireRea Valley3,219Shrewsbury and Atcham1,430677133100300002,370
ShropshireSevern Valley3,317Shrewsbury and Atcham1,72755910227270002,442
ShropshireSundorne3,355Shrewsbury and Atcham8371,44111940330002,470
ShropshireTern3,401Shrewsbury and Atcham1,63862717632310002,504
ShropshireUnderdale3,427Shrewsbury and Atcham1,098919335121500002,523
 Total81,495 30,15122,8604,5331,3631,09400060,001

And these are the implied results for 2017 for the new seat of Shrewsbury.


© 2018 Electoral Calculus Ltd
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