Preston: New Boundaries 2018 Calculation

Preston: Overview

 Projection: LAB seat 

Implied MP at 2017: Mark Hendrick  (LAB)
County/Area: Lancashire (North West)
Electorate: 77,324
Turnout: 67.3%

 Implied 2017 VotesImplied 2017 Share
LAB30,97559.5%
CON16,43031.6%
LIB2,6735.1%
UKIP1,3452.6%
Green6131.2%
LAB Majority14,54528.0%

See overview of other seats in North West.

Preston : Political and Demographic indicators

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

IndicatorSeatNorth WestAll GB
Party WinnerLABLABCON
Economic Position6° Left6° Left
National Position2° Nat2° Nat1° Int
EU Leave %54%54%52%
British Identity27%28%29%
Good Health47%46%48%
UK Born90%92%88%
Good Education44%37%39%
Good Job47%49%51%
High SEC44%48%51%
Average Age44.448.648.5
ABC1 Class52%50%53%

Preston ranks #300 for "Leave", #438 for "Right" and #314 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

Preston: 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 Preston 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 Preston

The old seat(s) needed are:

Old seat: Preston

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

Old seat: PrestonTransfer-adjusted Results
DistrictWardElectorate
2017
New SeatCON
Votes
LAB
Votes
LIB
Votes
UKIP
Votes
Green
Votes
NAT
Votes
MIN
Votes
OTH
Votes
Total
Votes
PrestonAshton2,765Preston63189312817340001,703
PrestonBrookfield4,395Preston7231,7032425170002,708
PrestonDeepdale3,783Preston3441,953134150002,329
PrestonFishwick3,510Preston4491,673142420002,162
PrestonIngol4,499Preston8401,33639319920002,770
PrestonLarches4,562Preston8141,631246103170002,811
PrestonMoor Park3,120Preston4111,3465771370001,922
PrestonPreston Rural East189Lancashire North7436320000115
PrestonRibbleton5,245Preston6772,22914301100003,231
PrestonRiversway3,778Preston5901,5794357590002,328
PrestonSt George's4,246Preston3842,147585220002,616
PrestonSt Matthew's4,992Preston5152,4111113800003,075
PrestonTown Centre5,344Preston7562,4145615500003,291
PrestonTulketh4,573Preston8091,74672150400002,817
PrestonUniversity2,791Preston4711,1157110520001,719
 Total57,792 8,48824,2121,2031,34734700035,597

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

Old seat: Wyre and Preston North

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

Old seat: Wyre and Preston NorthTransfer-adjusted Results
DistrictWardElectorate
2017
New SeatCON
Votes
LAB
Votes
LIB
Votes
UKIP
Votes
Green
Votes
NAT
Votes
MIN
Votes
OTH
Votes
Total
Votes
PrestonCadley3,829Preston1,1081,0565900330002,787
PrestonCollege3,032Preston1,0219861510490002,207
PrestonGarrison5,479Preston2,0161,6982050700003,989
PrestonGreyfriars5,248Preston2,1361,3502880470003,821
PrestonPreston Rural East3,515Lancashire North1,751736550170002,559
PrestonPreston Rural North5,509Lancashire North2,6639633350510004,012
PrestonSharoe Green5,150Preston1,7351,7092390670003,750
WyreBourne2,008Blackpool North and Fleetwood624771380290001,462
WyreBreck3,126Blackpool North and Fleetwood1,412797230430002,275
WyreBrock with Catterall3,384Lancashire North1,867457660730002,463
WyreCalder1,785Lancashire North767402720590001,300
WyreCarleton3,733Blackpool North and Fleetwood1,5811,053470360002,717
WyreGarstang5,306Lancashire North2,2381,4191550500003,862
WyreGreat Eccleston3,198Lancashire North1,621558630870002,329
WyreHambleton and Stalmine3,488Lancashire North1,670803180470002,538
WyreHardhorn with High Cross4,921Fylde2,3281,122740590003,583
WyreMarsh Mill2,319Blackpool North and Fleetwood869744510240001,688
WyreStanah3,850Blackpool North and Fleetwood1,7211,002290510002,803
WyreTithebarn3,440Fylde1,557812530830002,505
 Total72,320 30,68518,4382,552097500052,650

The full details of these calculations are given on the Wyre and Preston North seat details page. Click on "Show workings".

New seat: Preston

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

New seat: Preston
DistrictWardElectorate
2017
Old Seat CON
Votes
LAB
Votes
LIB
Votes
UKIP
Votes
Green
Votes
NAT
Votes
MIN
Votes
OTH
Votes
Total
Votes
PrestonAshton2,993Preston63189312817340001,703
PrestonBrookfield5,003Preston7231,7032425170002,708
PrestonCadley3,582Wyre and Preston North1,1081,0565900330002,787
PrestonCollege2,700Wyre and Preston North1,0219861510490002,207
PrestonDeepdale3,595Preston3441,953134150002,329
PrestonFishwick3,260Preston4491,673142420002,162
PrestonGarrison5,282Wyre and Preston North2,0161,6982050700003,989
PrestonGreyfriars5,188Wyre and Preston North2,1361,3502880470003,821
PrestonIngol5,038Preston8401,33639319920002,770
PrestonLarches5,410Preston8141,631246103170002,811
PrestonMoor Park2,830Preston4111,3465771370001,922
PrestonRibbleton5,337Preston6772,22914301100003,231
PrestonRiversway3,738Preston5901,5794357590002,328
PrestonSharoe Green4,679Wyre and Preston North1,7351,7092390670003,750
PrestonSt George's3,171Preston3842,147585220002,616
PrestonSt Matthew's4,285Preston5152,4111113800003,075
PrestonTown Centre4,749Preston7562,4145615500003,291
PrestonTulketh4,593Preston8091,74672150400002,817
PrestonUniversity1,891Preston4711,1157110520001,719
 Total77,324 16,43030,9752,6731,34561300052,036

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


© 2017 Martin Baxter
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