New Seat Details - Welwyn Hatfield

This page shows the detail of the calculations performed to estimate the general election result for 2017 had the new boundaries for Welwyn Hatfield 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	28,418	52.2%
LAB	19,488	35.8%
LIB	3,987	7.3%
UKIP	1,438	2.6%
Green	949	1.7%
OTH	177	0.3%
CON Majority	8,930	16.4%

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.

Welwyn Hatfield: Map

List of old seats forming part of Welwyn Hatfield

Old seat: Hertfordshire North East

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

Old seat: Hertfordshire North East				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
East Hertfordshire	Braughing	2,061	Letchworth and Royston	1,024	315	60	0	88	0	0	0	1,487
East Hertfordshire	Buntingford	4,289	Letchworth and Royston	2,084	736	163	0	157	0	0	0	3,140
East Hertfordshire	Hertford Rural North	1,769	Welwyn Hatfield	980	232	52	0	72	0	0	0	1,336
East Hertfordshire	Hertford Rural South	1,968	Welwyn Hatfield	1,077	258	103	0	43	0	0	0	1,481
East Hertfordshire	Little Hadham	1,857	Letchworth and Royston	1,032	270	53	0	89	0	0	0	1,444
East Hertfordshire	Mundens and Cottered	1,927	Letchworth and Royston	1,060	305	47	0	39	0	0	0	1,451
East Hertfordshire	Puckeridge	2,032	Letchworth and Royston	991	386	77	0	89	0	0	0	1,543
East Hertfordshire	Thundridge and Standon	2,180	Letchworth and Royston	1,284	391	72	0	52	0	0	0	1,799
East Hertfordshire	Walkern	2,085	Stevenage	1,134	370	62	0	47	0	0	0	1,613
East Hertfordshire	Watton-at-Stone	1,880	Stevenage	935	288	69	0	67	0	0	0	1,359
North Hertfordshire	Arbury	2,045	Letchworth and Royston	1,059	282	149	0	98	0	0	0	1,588
North Hertfordshire	Baldock East	2,251	Letchworth and Royston	930	382	290	0	80	0	0	0	1,682
North Hertfordshire	Baldock Town	5,647	Letchworth and Royston	2,500	1,261	266	0	267	0	0	0	4,294
North Hertfordshire	Ermine	1,949	Letchworth and Royston	1,102	261	62	0	94	0	0	0	1,519
North Hertfordshire	Letchworth East	4,222	Letchworth and Royston	1,352	1,450	205	0	213	0	0	0	3,220
North Hertfordshire	Letchworth Grange	5,492	Letchworth and Royston	2,029	1,658	345	0	225	0	0	0	4,257
North Hertfordshire	Letchworth South East	5,415	Letchworth and Royston	2,204	1,600	245	0	212	0	0	0	4,261
North Hertfordshire	Letchworth South West	5,910	Letchworth and Royston	2,554	1,217	498	0	316	0	0	0	4,585
North Hertfordshire	Letchworth Wilbury	3,905	Letchworth and Royston	1,313	1,413	192	0	169	0	0	0	3,087
North Hertfordshire	Royston Heath	4,166	Letchworth and Royston	1,754	740	395	0	154	0	0	0	3,043
North Hertfordshire	Royston Meridian	4,078	Letchworth and Royston	1,911	706	354	0	167	0	0	0	3,138
North Hertfordshire	Royston Palace	3,964	Letchworth and Royston	1,570	994	319	0	153	0	0	0	3,036
North Hertfordshire	Weston and Sandon	1,637	Letchworth and Royston	708	236	198	0	74	0	0	0	1,216
	Total	72,729		32,587	15,751	4,276	0	2,965	0	0	0	55,579

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

Old seat: Welwyn Hatfield

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

Old seat: Welwyn Hatfield				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
St Albans	Colney Heath	38	St Albans	14	9	4	1	1	0	0	0	29
Welwyn Hatfield	Brookmans Park and Little Heath	4,516	Welwyn Hatfield	2,109	580	128	41	34	0	0	2	2,894
Welwyn Hatfield	Haldens	4,667	Welwyn Hatfield	1,421	1,338	212	106	56	0	0	5	3,138
Welwyn Hatfield	Handside	5,130	Welwyn Hatfield	1,872	916	429	49	66	0	0	5	3,337
Welwyn Hatfield	Hatfield Central	4,137	Welwyn Hatfield	1,383	1,665	231	118	60	0	0	19	3,476
Welwyn Hatfield	Hatfield East	4,501	Welwyn Hatfield	1,687	1,236	223	102	56	0	0	19	3,323
Welwyn Hatfield	Hatfield South	3,036	Welwyn Hatfield	1,409	1,757	365	124	45	0	0	31	3,731
Welwyn Hatfield	Hatfield Villages	3,522	Welwyn Hatfield	2,114	1,546	236	124	70	0	0	7	4,097
Welwyn Hatfield	Hatfield West	5,218	Welwyn Hatfield	2,031	1,933	317	151	79	0	0	22	4,533
Welwyn Hatfield	Hollybush	4,985	Welwyn Hatfield	1,733	1,460	199	112	54	0	0	5	3,563
Welwyn Hatfield	Howlands	4,398	Welwyn Hatfield	1,436	1,185	189	97	51	0	0	5	2,963
Welwyn Hatfield	Panshanger	4,671	Welwyn Hatfield	1,765	1,088	193	114	49	0	0	22	3,231
Welwyn Hatfield	Peartree	5,135	Welwyn Hatfield	1,426	1,686	433	120	63	0	0	5	3,733
Welwyn Hatfield	Sherrards	4,319	Welwyn Hatfield	1,631	954	220	46	51	0	0	4	2,906
Welwyn Hatfield	Welham Green	2,788	Welwyn Hatfield	1,011	520	208	65	23	0	0	2	1,829
Welwyn Hatfield	Welwyn East	4,787	Welwyn Hatfield	2,065	609	160	38	40	0	0	8	2,920
Welwyn Hatfield	Welwyn West	3,216	Welwyn Hatfield	1,268	525	89	31	37	0	0	16	1,966
	Total	69,064		26,375	19,007	3,836	1,439	835	0	0	177	51,669

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

New seat: Welwyn Hatfield

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: Welwyn Hatfield
East Hertfordshire	Hertford Rural North	1,826	Hertfordshire North East	980	232	52	0	72	0	0	0	1,336
East Hertfordshire	Hertford Rural South	2,024	Hertfordshire North East	1,077	258	103	0	43	0	0	0	1,481
Welwyn Hatfield	Brookmans Park and Little Heath	4,083	Welwyn Hatfield	2,109	580	128	41	34	0	0	2	2,894
Welwyn Hatfield	Haldens	4,426	Welwyn Hatfield	1,421	1,338	212	106	56	0	0	5	3,138
Welwyn Hatfield	Handside	4,709	Welwyn Hatfield	1,872	916	429	49	66	0	0	5	3,337
Welwyn Hatfield	Hatfield Central	4,904	Welwyn Hatfield	1,383	1,665	231	118	60	0	0	19	3,476
Welwyn Hatfield	Hatfield East	4,689	Welwyn Hatfield	1,687	1,236	223	102	56	0	0	19	3,323
Welwyn Hatfield	Hatfield South	5,263	Welwyn Hatfield	1,409	1,757	365	124	45	0	0	31	3,731
Welwyn Hatfield	Hatfield Villages	5,781	Welwyn Hatfield	2,114	1,546	236	124	70	0	0	7	4,097
Welwyn Hatfield	Hatfield West	6,394	Welwyn Hatfield	2,031	1,933	317	151	79	0	0	22	4,533
Welwyn Hatfield	Hollybush	5,024	Welwyn Hatfield	1,733	1,460	199	112	54	0	0	5	3,563
Welwyn Hatfield	Howlands	4,180	Welwyn Hatfield	1,436	1,185	189	97	51	0	0	5	2,963
Welwyn Hatfield	Panshanger	4,557	Welwyn Hatfield	1,765	1,088	193	114	49	0	0	22	3,231
Welwyn Hatfield	Peartree	5,267	Welwyn Hatfield	1,426	1,686	433	120	63	0	0	5	3,733
Welwyn Hatfield	Sherrards	4,098	Welwyn Hatfield	1,631	954	220	46	51	0	0	4	2,906
Welwyn Hatfield	Welham Green	2,581	Welwyn Hatfield	1,011	520	208	65	23	0	0	2	1,829
Welwyn Hatfield	Welwyn East	4,119	Welwyn Hatfield	2,065	609	160	38	40	0	0	8	2,920
Welwyn Hatfield	Welwyn West	2,774	Welwyn Hatfield	1,268	525	89	31	37	0	0	16	1,966
	Total	76,699		28,418	19,488	3,987	1,438	949	0	0	177	54,457

And these are the implied results for 2017 for the new seat of Welwyn Hatfield. 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:	Grant Shapps (CON)
County/Area:	Hertfordshire (Anglia)
Electorate:	76,699
Turnout:	71.0%

Welwyn Hatfield: New Boundaries 2018 Calculation

Welwyn Hatfield: Overview

Introduction