New Seat Details - Dursley, Thornbury and Yate

This page shows the detail of the calculations performed to estimate the general election result for 2017 had the new boundaries for Dursley, Thornbury and Yate 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.

Party	Implied 2017 Votes	Implied 2017 Share
CON	30,170	52.3%
LIB	15,004	26.0%
LAB	11,274	19.6%
Green	948	1.6%
UKIP	242	0.4%
OTH	26	0.0%
CON Majority	15,166	26.3%

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.

Dursley, Thornbury and Yate: Map

List of old seats forming part of Dursley, Thornbury and Yate

Old seat: Cotswolds, The

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

Old seat: Cotswolds, The				Transfer-adjusted Results
District	Ward	Electorate 2017	New Seat	CON Votes	LAB Votes	LIB Votes	UKIP Votes	Green Votes	NAT Votes	MIN Votes	OTH Votes	Total Votes
Cotswold	Abbey	1,859	Cotswolds, The	835	333	387	27	98	0	0	2	1,682
Cotswold	Blockley	2,121	Cotswolds, The	1,035	255	285	21	31	0	0	3	1,630
Cotswold	Bourton Vale	2,164	Cotswolds, The	1,205	232	204	23	28	0	0	4	1,696
Cotswold	Bourton Village	1,989	Cotswolds, The	875	304	317	25	29	0	0	1	1,551
Cotswold	Campden and Vale	4,331	Cotswolds, The	2,230	486	390	119	58	0	0	4	3,287
Cotswold	Chedworth and Churn Valley	1,975	Cotswolds, The	1,072	226	301	16	28	0	0	1	1,644
Cotswold	Chesterton	1,814	Cotswolds, The	749	351	344	63	85	0	0	1	1,593
Cotswold	Coln Valley	1,948	Cotswolds, The	1,128	207	137	15	73	0	0	3	1,563
Cotswold	Ermin	1,994	Cotswolds, The	1,061	213	235	50	26	0	0	1	1,586
Cotswold	Fairford North	1,825	Cotswolds, The	817	249	213	51	24	0	0	1	1,355
Cotswold	Fosseridge	2,065	Cotswolds, The	1,182	209	149	21	80	0	0	1	1,642
Cotswold	Four Acres	1,431	Cotswolds, The	584	240	274	18	67	0	0	1	1,184
Cotswold	Grumbolds Ash with Avening	2,005	Cotswolds, The	1,105	239	208	16	30	0	0	1	1,599
Cotswold	Kemble	2,003	Cotswolds, The	1,021	232	256	51	27	0	0	1	1,588
Cotswold	Lechlade, Kempsford and Fairford South	4,184	Cotswolds, The	2,093	526	332	118	59	0	0	5	3,133
Cotswold	Moreton East	1,897	Cotswolds, The	781	242	120	12	21	0	0	1	1,177
Cotswold	Moreton West	1,881	Cotswolds, The	949	257	160	24	26	0	0	1	1,417
Cotswold	New Mills	1,848	Cotswolds, The	562	263	242	20	21	0	0	2	1,110
Cotswold	Northleach	2,074	Cotswolds, The	1,093	277	289	19	30	0	0	2	1,710
Cotswold	Sandywell	2,098	Cotswolds, The	1,106	219	208	16	27	0	0	1	1,577
Cotswold	Siddington and Cerney Rural	1,887	Cotswolds, The	1,027	275	327	23	28	0	0	1	1,681
Cotswold	South Cerney Village	1,943	Cotswolds, The	785	266	346	22	25	0	0	5	1,449
Cotswold	St Michael's	1,857	Cotswolds, The	700	304	341	58	78	0	0	5	1,486
Cotswold	Stow	2,081	Cotswolds, The	975	267	301	25	32	0	0	3	1,603
Cotswold	Stratton	2,018	Cotswolds, The	872	277	346	23	85	0	0	1	1,604
Cotswold	Tetbury East and Rural	1,549	Cotswolds, The	861	276	143	17	24	0	0	1	1,322
Cotswold	Tetbury Town	1,602	Cotswolds, The	753	377	139	18	28	0	0	5	1,320
Cotswold	Tetbury with Upton	1,686	Cotswolds, The	844	309	143	18	27	0	0	1	1,342
Cotswold	The Ampneys and Hampton	2,133	Cotswolds, The	1,164	237	280	19	29	0	0	4	1,733
Cotswold	The Beeches	2,023	Cotswolds, The	701	319	324	55	29	0	0	1	1,429
Cotswold	The Rissingtons	1,511	Cotswolds, The	758	172	107	14	57	0	0	2	1,110
Cotswold	Watermoor	2,029	Cotswolds, The	827	445	433	79	39	0	0	2	1,825
Stroud	Kingswood	1,662	Dursley, Thornbury and Yate	734	258	307	16	29	0	0	6	1,350
Stroud	Minchinhampton	3,624	Stroud	1,712	540	285	34	143	0	0	12	2,726
Stroud	Wotton-under-Edge	5,109	Dursley, Thornbury and Yate	2,006	821	877	52	223	0	0	20	3,999
	Total	76,220		36,202	10,703	9,750	1,198	1,744	0	0	106	59,703

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

Old seat: Stroud

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

Old seat: Stroud				Transfer-adjusted Results
District	Ward	Electorate 2017	New Seat	CON Votes	LAB Votes	LIB Votes	UKIP Votes	Green Votes	NAT Votes	MIN Votes	OTH Votes	Total Votes
Stroud	Amberley and Woodchester	1,714	Stroud	814	454	27	11	30	0	0	0	1,336
Stroud	Berkeley	3,454	Stroud	1,299	1,247	55	27	50	0	0	0	2,678
Stroud	Bisley	1,841	Stroud	733	477	27	40	29	0	0	0	1,306
Stroud	Cainscross	5,798	Stroud	1,762	2,587	150	59	107	0	0	0	4,665
Stroud	Cam East	3,465	Dursley, Thornbury and Yate	1,351	1,147	61	29	51	0	0	0	2,639
Stroud	Cam West	3,261	Dursley, Thornbury and Yate	1,053	1,327	55	84	50	0	0	0	2,569
Stroud	Central	1,722	Stroud	514	774	51	18	41	0	0	0	1,398
Stroud	Chalford	5,096	Stroud	2,219	1,651	112	130	96	0	0	0	4,208
Stroud	Coaley and Uley	1,935	Stroud	808	577	34	13	36	0	0	0	1,468
Stroud	Dursley	5,128	Dursley, Thornbury and Yate	1,609	2,302	277	51	49	0	0	0	4,288
Stroud	Eastington and Standish	1,499	Stroud	537	545	27	11	24	0	0	0	1,144
Stroud	Farmhill and Paganhill	1,647	Stroud	578	699	45	47	33	0	0	0	1,402
Stroud	Hardwicke	4,408	Stroud	1,651	1,255	71	37	60	0	0	0	3,074
Stroud	Nailsworth	5,245	Stroud	1,997	1,969	119	40	104	0	0	0	4,229
Stroud	Painswick	1,487	Stroud	1,572	920	56	74	62	0	0	0	2,684
Stroud	Randwick, Whiteshill and Ruscombe	3,688	Stroud	450	567	42	10	32	0	0	0	1,101
Stroud	Rodborough	3,566	Stroud	1,111	1,443	253	30	79	0	0	0	2,916
Stroud	Severn	3,801	Stroud	1,763	1,157	52	30	57	0	0	0	3,059
Stroud	Slade	1,546	Stroud	408	772	44	18	37	0	0	0	1,279
Stroud	Stonehouse	6,082	Stroud	1,822	2,800	146	57	103	0	0	0	4,928
Stroud	The Stanleys	3,361	Stroud	1,157	1,158	70	83	59	0	0	0	2,527
Stroud	Thrupp	1,878	Stroud	663	681	53	57	44	0	0	0	1,498
Stroud	Trinity	1,701	Stroud	524	774	66	17	50	0	0	0	1,431
Stroud	Uplands	1,661	Stroud	518	798	41	18	35	0	0	0	1,410
Stroud	Upton St Leonards	2,411	Stroud	1,113	636	33	19	34	0	0	0	1,835
Stroud	Vale	1,562	Dursley, Thornbury and Yate	766	383	16	10	20	0	0	0	1,195
Stroud	Valley	1,942	Stroud	512	895	71	17	53	0	0	0	1,548
	Total	80,899		29,304	29,995	2,054	1,037	1,425	0	0	0	63,815

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

Old seat: Thornbury and Yate

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

Old seat: Thornbury and Yate				Transfer-adjusted Results
District	Ward	Electorate 2017	New Seat	CON Votes	LAB Votes	LIB Votes	UKIP Votes	Green Votes	NAT Votes	MIN Votes	OTH Votes	Total Votes
South Gloucestershire	Boyd Valley	5,815	Kingswood	2,829	561	1,119	0	56	0	0	0	4,565
South Gloucestershire	Charfield	3,145	Dursley, Thornbury and Yate	1,612	194	1,014	0	30	0	0	0	2,850
South Gloucestershire	Chipping Sodbury	5,454	Dursley, Thornbury and Yate	2,353	475	1,305	0	57	0	0	0	4,190
South Gloucestershire	Cotswold Edge	2,725	Dursley, Thornbury and Yate	1,275	113	640	0	20	0	0	0	2,048
South Gloucestershire	Dodington	5,778	Dursley, Thornbury and Yate	2,268	874	1,716	0	61	0	0	0	4,919
South Gloucestershire	Frampton Cotterell	6,040	Filton and Bradley Stoke	2,529	513	1,408	0	51	0	0	0	4,501
South Gloucestershire	Ladden Brook	3,101	Dursley, Thornbury and Yate	1,472	221	653	0	25	0	0	0	2,371
South Gloucestershire	Severn	3,010	Dursley, Thornbury and Yate	1,719	127	356	0	22	0	0	0	2,224
South Gloucestershire	Thornbury North	6,178	Dursley, Thornbury and Yate	2,501	579	1,483	0	71	0	0	0	4,634
South Gloucestershire	Thornbury South and Alveston	5,982	Dursley, Thornbury and Yate	2,481	518	1,467	0	64	0	0	0	4,530
South Gloucestershire	Westerleigh	3,164	Dursley, Thornbury and Yate	1,352	179	717	0	25	0	0	0	2,273
South Gloucestershire	Yate Central	6,406	Dursley, Thornbury and Yate	2,127	753	1,652	0	61	0	0	0	4,593
South Gloucestershire	Yate North	8,771	Dursley, Thornbury and Yate	3,491	1,003	2,408	0	90	0	0	0	6,992
	Total	65,569		28,009	6,110	15,938	0	633	0	0	0	50,690

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

New seat: Dursley, Thornbury and Yate

District	Ward	Electorate 2017	Old Seat	CON Votes	LAB Votes	LIB Votes	UKIP Votes	Green Votes	NAT Votes	MIN Votes	OTH Votes	Total Votes
New seat: Dursley, Thornbury and Yate
South Gloucestershire	Charfield	3,820	Thornbury and Yate	1,612	194	1,014	0	30	0	0	0	2,850
South Gloucestershire	Chipping Sodbury	5,614	Thornbury and Yate	2,353	475	1,305	0	57	0	0	0	4,190
South Gloucestershire	Cotswold Edge	2,745	Thornbury and Yate	1,275	113	640	0	20	0	0	0	2,048
South Gloucestershire	Dodington	6,593	Thornbury and Yate	2,268	874	1,716	0	61	0	0	0	4,919
South Gloucestershire	Ladden Brook	3,178	Thornbury and Yate	1,472	221	653	0	25	0	0	0	2,371
South Gloucestershire	Severn	2,978	Thornbury and Yate	1,719	127	356	0	22	0	0	0	2,224
South Gloucestershire	Thornbury North	6,211	Thornbury and Yate	2,501	579	1,483	0	71	0	0	0	4,634
South Gloucestershire	Thornbury South and Alveston	6,071	Thornbury and Yate	2,481	518	1,467	0	64	0	0	0	4,530
South Gloucestershire	Westerleigh	3,045	Thornbury and Yate	1,352	179	717	0	25	0	0	0	2,273
South Gloucestershire	Yate Central	6,155	Thornbury and Yate	2,127	753	1,652	0	61	0	0	0	4,593
South Gloucestershire	Yate North	9,370	Thornbury and Yate	3,491	1,003	2,408	0	90	0	0	0	6,992
Stroud	Cam East	3,427	Stroud	1,351	1,147	61	29	51	0	0	0	2,639
Stroud	Cam West	3,337	Stroud	1,053	1,327	55	84	50	0	0	0	2,569
Stroud	Dursley	5,567	Stroud	1,609	2,302	277	51	49	0	0	0	4,288
Stroud	Kingswood	1,819	Cotswolds, The	734	258	307	16	29	0	0	6	1,350
Stroud	Vale	1,551	Stroud	766	383	16	10	20	0	0	0	1,195
Stroud	Wotton-under-Edge	5,389	Cotswolds, The	2,006	821	877	52	223	0	0	20	3,999
	Total	76,870		30,170	11,274	15,004	242	948	0	0	26	57,664

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

Implied MP at 2017:	Luke Hall (CON)
County/Area:	Bristol area (South West)
Electorate:	76,870
Turnout:	75.0%

Dursley, Thornbury and Yate: New Boundaries 2018 Calculation

Dursley, Thornbury and Yate: Overview

Introduction