New Seat Details - Brentwood and Ongar

This page shows the detail of the calculations performed to estimate the general election result for 2017 had the new boundaries for Brentwood and Ongar 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	36,088	64.9%
LAB	11,567	20.8%
LIB	5,001	9.0%
UKIP	2,052	3.7%
Green	787	1.4%
OTH	95	0.2%
CON Majority	24,521	44.1%

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.

Brentwood and Ongar: Map

List of old seats forming part of Brentwood and Ongar

Old seat: Brentwood and Ongar

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

Old seat: Brentwood and Ongar				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
Brentwood	Brentwood North	5,054	Brentwood and Ongar	1,972	944	511	151	68	0	0	10	3,656
Brentwood	Brentwood South	4,204	Brentwood and Ongar	1,761	1,093	258	127	54	0	0	3	3,296
Brentwood	Brentwood West	5,096	Brentwood and Ongar	2,374	1,002	503	82	66	0	0	3	4,030
Brentwood	Brizes and Doddinghurst	4,648	Brentwood and Ongar	2,422	570	197	134	37	0	0	6	3,366
Brentwood	Herongate, Ingrave and West Horndon	2,970	Brentwood and Ongar	1,534	349	101	90	26	0	0	9	2,109
Brentwood	Hutton Central	2,950	Brentwood and Ongar	1,556	368	168	40	27	0	0	9	2,168
Brentwood	Hutton East	2,873	Brentwood and Ongar	1,363	452	162	84	30	0	0	1	2,092
Brentwood	Hutton North	3,085	Brentwood and Ongar	1,584	540	188	55	36	0	0	7	2,410
Brentwood	Hutton South	3,029	Brentwood and Ongar	1,621	348	98	93	27	0	0	9	2,196
Brentwood	Ingatestone, Fryerning and Mountnessing	4,795	Brentwood and Ongar	2,341	639	238	125	49	0	0	2	3,394
Brentwood	Pilgrims Hatch	4,497	Brentwood and Ongar	1,966	760	460	145	54	0	0	2	3,387
Brentwood	Shenfield	4,187	Brentwood and Ongar	2,113	479	347	102	46	0	0	4	3,091
Brentwood	South Weald	1,437	Brentwood and Ongar	782	190	56	51	15	0	0	4	1,098
Brentwood	Tipps Cross	3,115	Brentwood and Ongar	1,623	346	88	88	25	0	0	11	2,181
Brentwood	Warley	4,505	Brentwood and Ongar	1,987	788	429	133	58	0	0	2	3,397
Epping Forest	Chipping Ongar, Greensted and Marden Ash	3,435	Brentwood and Ongar	1,511	403	205	88	88	0	0	7	2,302
Epping Forest	Hastingwood, Matching and Sheering Village	174	Harlow	87	23	5	2	1	0	0	1	119
Epping Forest	High Ongar, Willingale and The Rodings	1,832	Brentwood and Ongar	995	178	43	22	43	0	0	3	1,284
Epping Forest	Lambourne	1,561	Brentwood and Ongar	840	199	47	44	13	0	0	1	1,144
Epping Forest	Moreton and Fyfield	1,661	Harlow	863	128	54	19	36	0	0	3	1,103
Epping Forest	North Weald Bassett	3,659	Harlow	1,725	474	153	99	91	0	0	4	2,546
Epping Forest	Passingford	1,884	Brentwood and Ongar	1,054	150	58	21	10	0	0	1	1,294
Epping Forest	Shelley	1,737	Brentwood and Ongar	739	387	56	49	15	0	0	1	1,247
	Total	72,388		34,813	10,810	4,425	1,844	915	0	0	103	52,910

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

Old seat: Saffron Walden

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

Old seat: Saffron Walden				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
Chelmsford	Boreham and The Leighs	4,691	Witham and Maldon	2,395	803	493	83	0	0	0	0	3,774
Chelmsford	Broomfield and The Walthams	6,367	Brentwood and Ongar	2,796	1,094	619	294	0	0	0	0	4,803
Chelmsford	Chelmsford Rural West	2,181	Brentwood and Ongar	1,154	288	169	34	0	0	0	0	1,645
Chelmsford	Writtle	4,151	Billericay	1,737	679	643	166	0	0	0	0	3,225
Uttlesford	Ashdon	1,560	Saffron Walden	771	226	105	77	0	0	0	0	1,179
Uttlesford	Broad Oak and the Hallingburys	3,033	Saffron Walden	1,646	403	191	138	0	0	0	0	2,378
Uttlesford	Clavering	1,776	Saffron Walden	938	212	124	25	0	0	0	0	1,299
Uttlesford	Debden and Wimbish	1,628	Saffron Walden	1,004	250	156	31	0	0	0	0	1,441
Uttlesford	Elsenham and Henham	2,800	Saffron Walden	1,118	447	537	54	0	0	0	0	2,156
Uttlesford	Felsted and Stebbing	3,268	Saffron Walden	1,705	480	253	164	0	0	0	0	2,602
Uttlesford	Flitch Green and Little Dunmow	1,546	Saffron Walden	1,032	293	136	31	0	0	0	0	1,492
Uttlesford	Great Dunmow North	3,154	Saffron Walden	1,504	528	238	59	0	0	0	0	2,329
Uttlesford	Great Dunmow South and Barnston	4,552	Saffron Walden	2,353	716	357	85	0	0	0	0	3,511
Uttlesford	Hatfield Heath	1,676	Saffron Walden	927	239	119	30	0	0	0	0	1,315
Uttlesford	High Easter and The Rodings	1,772	Saffron Walden	969	236	131	28	0	0	0	0	1,364
Uttlesford	Littlebury, Chesterford and Wenden Lofts	3,290	Saffron Walden	1,745	460	254	54	0	0	0	0	2,513
Uttlesford	Newport	2,652	Saffron Walden	1,307	455	253	51	0	0	0	0	2,066
Uttlesford	Saffron Walden Audley	3,315	Saffron Walden	1,436	622	633	67	0	0	0	0	2,758
Uttlesford	Saffron Walden Castle	3,002	Saffron Walden	1,206	713	293	110	0	0	0	0	2,322
Uttlesford	Saffron Walden Shire	5,194	Saffron Walden	2,370	1,073	493	114	0	0	0	0	4,050
Uttlesford	Stansted North	3,253	Saffron Walden	1,313	482	612	57	0	0	0	0	2,464
Uttlesford	Stansted South and Birchanger	3,091	Saffron Walden	1,093	449	476	47	0	0	0	0	2,065
Uttlesford	Stort Valley	1,559	Saffron Walden	705	210	255	23	0	0	0	0	1,193
Uttlesford	Takeley	4,300	Saffron Walden	1,872	607	261	186	0	0	0	0	2,926
Uttlesford	Thaxted and the Eastons	3,613	Saffron Walden	1,594	486	602	58	0	0	0	0	2,740
Uttlesford	The Sampfords	1,668	Saffron Walden	940	213	125	26	0	0	0	0	1,304
	Total	79,092		37,630	12,664	8,528	2,092	0	0	0	0	60,914

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

New seat: Brentwood and Ongar

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: Brentwood and Ongar
Brentwood	Brentwood North	5,177	Brentwood and Ongar	1,972	944	511	151	68	0	0	10	3,656
Brentwood	Brentwood South	4,668	Brentwood and Ongar	1,761	1,093	258	127	54	0	0	3	3,296
Brentwood	Brentwood West	5,706	Brentwood and Ongar	2,374	1,002	503	82	66	0	0	3	4,030
Brentwood	Brizes and Doddinghurst	4,766	Brentwood and Ongar	2,422	570	197	134	37	0	0	6	3,366
Brentwood	Herongate, Ingrave and West Horndon	2,986	Brentwood and Ongar	1,534	349	101	90	26	0	0	9	2,109
Brentwood	Hutton Central	3,070	Brentwood and Ongar	1,556	368	168	40	27	0	0	9	2,168
Brentwood	Hutton East	2,961	Brentwood and Ongar	1,363	452	162	84	30	0	0	1	2,092
Brentwood	Hutton North	3,414	Brentwood and Ongar	1,584	540	188	55	36	0	0	7	2,410
Brentwood	Hutton South	3,109	Brentwood and Ongar	1,621	348	98	93	27	0	0	9	2,196
Brentwood	Ingatestone, Fryerning and Mountnessing	4,805	Brentwood and Ongar	2,341	639	238	125	49	0	0	2	3,394
Brentwood	Pilgrims Hatch	4,796	Brentwood and Ongar	1,966	760	460	145	54	0	0	2	3,387
Brentwood	Shenfield	4,377	Brentwood and Ongar	2,113	479	347	102	46	0	0	4	3,091
Brentwood	South Weald	1,554	Brentwood and Ongar	782	190	56	51	15	0	0	4	1,098
Brentwood	Tipps Cross	3,087	Brentwood and Ongar	1,623	346	88	88	25	0	0	11	2,181
Brentwood	Warley	4,809	Brentwood and Ongar	1,987	788	429	133	58	0	0	2	3,397
Chelmsford	Broomfield and The Walthams	6,599	Saffron Walden	2,796	1,094	619	294	0	0	0	0	4,803
Chelmsford	Chelmsford Rural West	2,259	Saffron Walden	1,154	288	169	34	0	0	0	0	1,645
Epping Forest	Chipping Ongar, Greensted and Marden Ash	3,260	Brentwood and Ongar	1,511	403	205	88	88	0	0	7	2,302
Epping Forest	High Ongar, Willingale and The Rodings	1,817	Brentwood and Ongar	995	178	43	22	43	0	0	3	1,284
Epping Forest	Lambourne	1,620	Brentwood and Ongar	840	199	47	44	13	0	0	1	1,144
Epping Forest	Passingford	1,833	Brentwood and Ongar	1,054	150	58	21	10	0	0	1	1,294
Epping Forest	Shelley	1,764	Brentwood and Ongar	739	387	56	49	15	0	0	1	1,247
	Total	78,437		36,088	11,567	5,001	2,052	787	0	0	95	55,590

And these are the implied results for 2017 for the new seat of Brentwood and Ongar. 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:	Alex Burghart (CON)
County/Area:	Essex (Anglia)
Electorate:	78,437
Turnout:	70.9%

Brentwood and Ongar: New Boundaries 2018 Calculation

Brentwood and Ongar: Overview

Introduction