Arfon: New Boundaries Calculation

Due to changes in ward boundaries, some new wards are divided among several old constituencies (though never between two new constituencies). Such wards are shown divided into several parts, called [1], [2], and so on.

Election results from a recent local election are given. This is usually the local election from 2003, 2004 or 2006. 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. Where zero votes are shown, the ward is not needed because the entire old seat is unsplit.

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% of its votes from each ward. 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 on a ward-by-ward basis using these common percentages.

More details of the calculation formulas are available.

The old seat(s) needed are:

• Caernarfon
• Conwy

Old seat: Caernarfon

					Actual Results					Turnout-adjusted Results						Transfer-adjusted Results
District	Ward	Electorate 2005	Old Seat	New Seat	CON Votes	LAB Votes	LIB Votes	NAT Votes	OTH Votes	CON Votes	LAB Votes	LIB Votes	NAT Votes	OTH Votes	Total Votes	CON Votes	LAB Votes	LIB Votes	NAT Votes	OTH Votes	Total Votes
Gwynedd	Aberdaron	780	Caernarfon	Dwyfor Meirionnydd	0	0	0	264	200	0	0	0	264	200	464	73	120	67	182	19	464
Gwynedd	Abererch	1,057	Caernarfon	Dwyfor Meirionnydd	0	0	0	-1	0	0	0	0	629	0	629	54	89	50	434	0	629
Gwynedd	Abersoch	719	Caernarfon	Dwyfor Meirionnydd	0	0	0	-1	0	0	0	0	428	0	428	36	60	34	295	0	428
Gwynedd	Bethel	1,051	Caernarfon	Arfon	0	0	0	-1	0	0	0	0	625	0	625	53	88	49	432	0	625
Gwynedd	Bontnewydd	896	Caernarfon	Arfon	0	0	0	-1	0	0	0	0	533	0	533	45	75	42	368	0	533
Gwynedd	Botwnnog	734	Caernarfon	Dwyfor Meirionnydd	0	0	0	0	-1	0	0	0	0	437	437	110	182	102	0	42	437
Gwynedd	Cadnant	1,543	Caernarfon	Arfon	0	79	0	0	760	0	86	0	0	831	917	209	432	194	0	80	917
Gwynedd	Clynnog	774	Caernarfon	Dwyfor Meirionnydd	0	0	0	232	334	0	0	0	189	272	461	85	140	78	130	26	461
Gwynedd	Criccieth	1,528	Caernarfon	Dwyfor Meirionnydd	0	0	0	356	346	0	0	0	461	448	909	152	252	141	318	43	909
Gwynedd	Cwm-y-Glo	712	Caernarfon	Arfon	0	-1	0	0	0	0	424	0	0	0	424	0	424	0	0	0	424
Gwynedd	Deiniolen	1,371	Caernarfon	Arfon	0	0	0	-1	0	0	0	0	816	0	816	70	116	65	564	0	816
Gwynedd	Dolbenmaen	918	Caernarfon	Dwyfor Meirionnydd	0	0	323	311	0	0	0	278	268	0	546	23	38	299	185	0	546
Gwynedd	Efail-newydd/Buan	1,050	Caernarfon	Dwyfor Meirionnydd	0	0	0	-1	0	0	0	0	625	0	625	53	88	49	432	0	625
Gwynedd	Groeslon	1,302	Caernarfon	Arfon	0	0	0	-1	0	0	0	0	775	0	775	66	110	61	535	0	775
Gwynedd	Llanaelhaearn	1,208	Caernarfon	Dwyfor Meirionnydd	0	0	0	-1	0	0	0	0	719	0	719	62	102	57	497	0	719
Gwynedd	Llanbedrog	897	Caernarfon	Dwyfor Meirionnydd	0	0	0	-1	0	0	0	0	534	0	534	46	75	42	369	0	534
Gwynedd	Llanberis	1,461	Caernarfon	Arfon	0	0	0	273	624	0	0	0	265	605	870	175	289	162	183	58	870
Gwynedd	Llanengan	886	Caernarfon	Dwyfor Meirionnydd	0	0	0	237	361	0	0	0	209	318	527	98	162	91	144	30	527
Gwynedd	Llanllyfni	951	Caernarfon	Arfon	0	111	0	383	0	0	127	0	439	0	566	37	189	35	303	0	566
Gwynedd	Llanrug	1,372	Caernarfon	Arfon	0	0	0	-1	0	0	0	0	816	0	816	70	116	65	564	0	816
Gwynedd	Llanwnda	1,518	Caernarfon	Arfon	0	0	0	-1	0	0	0	0	903	0	903	77	128	72	624	0	903
Gwynedd	Llanystumdwy	1,551	Caernarfon	Dwyfor Meirionnydd	0	0	0	-1	0	0	0	0	923	0	923	79	131	73	638	0	923
Gwynedd	Menai (Caernarfon)	1,808	Caernarfon	Arfon	0	0	0	556	289	0	0	0	708	368	1,076	154	254	142	489	35	1,076
Gwynedd	Morfa Nefyn	1,030	Caernarfon	Dwyfor Meirionnydd	0	0	0	274	271	0	0	0	308	305	613	103	170	96	212	29	613
Gwynedd	Nefyn	1,072	Caernarfon	Dwyfor Meirionnydd	0	0	0	285	269	0	0	0	328	310	638	106	175	98	226	29	638
Gwynedd	Peblig (Caernarfon)	1,550	Caernarfon	Arfon	0	0	0	-1	0	0	0	0	922	0	922	79	131	73	637	0	922
Gwynedd	Penisarwaun	1,348	Caernarfon	Arfon	0	0	0	-1	0	0	0	0	802	0	802	69	114	64	554	0	802
Gwynedd	Penygroes	1,387	Caernarfon	Arfon	0	0	0	-1	0	0	0	0	825	0	825	71	117	65	570	0	825
Gwynedd	Porthmadog East	1,312	Caernarfon	Dwyfor Meirionnydd	0	0	0	315	335	0	0	0	378	402	780	134	221	124	261	38	780
Gwynedd	Porthmadog West	1,551	Caernarfon	Dwyfor Meirionnydd	0	0	0	442	416	0	0	0	475	447	922	153	253	142	328	43	922
Gwynedd	Porthmadog-Tremadog	1,087	Caernarfon	Dwyfor Meirionnydd	0	0	0	-1	0	0	0	0	647	0	647	55	92	51	447	0	647
Gwynedd	Pwllheli North	1,670	Caernarfon	Dwyfor Meirionnydd	0	0	0	409	312	0	0	0	564	430	994	157	259	145	390	41	994
Gwynedd	Pwllheli South	1,493	Caernarfon	Dwyfor Meirionnydd	0	0	0	-1	0	0	0	0	888	0	888	76	126	71	614	0	888
Gwynedd	Seiont	2,391	Caernarfon	Arfon	0	879	0	443	633	0	640	0	322	461	1,423	144	877	133	222	44	1,423
Gwynedd	Talysarn	1,385	Caernarfon	Arfon	0	0	0	296	319	0	0	0	397	427	824	142	234	131	274	41	824
Gwynedd	Tudweiliog	754	Caernarfon	Dwyfor Meirionnydd	0	0	0	-1	0	0	0	0	449	0	449	38	63	35	310	0	449
Gwynedd	Waunfawr	1,279	Caernarfon	Arfon	0	0	0	0	-1	0	0	0	0	761	761	192	317	178	0	73	761
Gwynedd	Y Felinheli	1,669	Caernarfon	Arfon	0	384	0	0	354	0	517	0	0	476	993	120	715	111	0	45	993
	Total		Caernarfon							0	1,794	278	18,434	7,498	28,004	3,484	7,540	3,509	12,747	723	28,004

The transfer table below shows the votes cast in the old seat of Caernarfon at the general election, as well as the total local turnout-adjusted votes. The number of votes to transfer, shown in the fourth and fifth columns, are the difference between the general and local votes. Strong parties will have votes transferred away, and weak parties will have votes transferred into them. The final column describes how votes will be transferred away from or into that party on a ward-by-ward basis. If a party is too strong, it will lose a percentage of its votes in each ward which go into that ward's transfer pool. If a party is too weak, it will gain votes from each ward's transfer pool in proportion to the number of transfer votes it needs over the whole old seat.

Party	General Election 2005 Votes	Local Election Turnout-adjusted Votes	Votes to transfer away	Votes to transfer into	Ward Transfers needed
CON	3,483	0	0	3,483	Transfer in 28.0% (= 3483 / 12457) of ward's transfer pool votes
LAB	7,538	1,794	0	5,744	Transfer in 46.1% (= 5744 / 12457) of ward's transfer pool votes
LIB	3,508	278	0	3,230	Transfer in 25.9% (= 3230 / 12457) of ward's transfer pool votes
NAT	12,747	18,434	5,687	0	Transfer away 30.9% (= 5687 / 18434) of ward's NAT votes
OTH	723	7,498	6,775	0	Transfer away 90.4% (= 6775 / 7498) of ward's OTH votes
Total	27,999	28,004	12,457	12,457

After transfer adjustment, the totals for each party over all the wards match the general election vote in the old seat.

Old seat: Conwy

					Actual Results					Turnout-adjusted Results						Transfer-adjusted Results
District	Ward	Electorate 2005	Old Seat	New Seat	CON Votes	LAB Votes	LIB Votes	NAT Votes	OTH Votes	CON Votes	LAB Votes	LIB Votes	NAT Votes	OTH Votes	Total Votes	CON Votes	LAB Votes	LIB Votes	NAT Votes	OTH Votes	Total Votes
Conwy	Bryn	1,383	Conwy	Aberconwy	0	495	179	0	0	0	621	225	0	0	846	13	627	205	0	0	846
Conwy	Caerhun	1,560	Conwy	Aberconwy	0	234	0	0	675	0	246	0	0	709	955	374	423	0	0	156	955
Conwy	Capelulo	1,209	Conwy	Aberconwy	109	129	90	0	212	149	177	123	0	290	739	309	253	112	0	64	739
Conwy	Conwy	3,233	Conwy	Aberconwy	215	429	221	628	705	193	386	199	565	634	1,977	715	634	181	304	140	1,977
Conwy	Craig-y-Don	2,837	Conwy	Aberconwy	892	113	579	664	192	635	80	412	472	137	1,736	878	195	376	254	30	1,736
Conwy	Deganwy	3,197	Conwy	Aberconwy	958	413	752	0	325	765	330	601	0	260	1,956	937	412	548	0	57	1,956
Conwy	Gogarth	3,042	Conwy	Aberconwy	704	467	365	0	612	610	405	316	0	530	1,861	908	546	288	0	117	1,861
Conwy	Llansanffraid	1,860	Conwy	Aberconwy	0	0	-1	0	0	0	0	1,138	0	0	1,138	66	31	1,039	0	0	1,138
Conwy	Marl	2,976	Conwy	Aberconwy	0	867	797	0	0	0	949	872	0	0	1,821	51	973	796	0	0	1,821
Conwy	Mostyn (Conwy)	2,700	Conwy	Aberconwy	287	1,009	342	0	394	233	820	278	0	320	1,651	418	908	253	0	70	1,651
Conwy	Pandy	1,428	Conwy	Aberconwy	0	164	475	206	0	0	170	491	213	0	874	95	215	448	114	0	874
Conwy	Pant-yr-afon/Penmaenan	2,067	Conwy	Aberconwy	101	587	142	0	62	143	832	201	0	88	1,264	201	859	183	0	19	1,264
Conwy	Penrhyn	3,825	Conwy	Aberconwy	829	449	378	0	1,479	619	335	282	0	1,104	2,340	1,218	619	257	0	244	2,340
Conwy	Pensarn	2,091	Conwy	Aberconwy	0	164	353	364	0	0	238	513	529	0	1,280	195	330	468	285	0	1,280
Conwy	Tudno	3,597	Conwy	Aberconwy	346	792	0	285	1,193	291	666	0	240	1,004	2,201	895	953	0	129	222	2,201
Gwynedd	Arllechwedd	1,059	Conwy	Arfon	0	0	290	267	0	0	0	337	311	0	648	116	55	307	167	0	648
Gwynedd	Deiniol	1,014	Conwy	Arfon	0	54	56	77	0	0	179	186	255	0	620	90	222	169	137	0	620
Gwynedd	Dewi	1,217	Conwy	Arfon	0	364	38	135	0	0	505	53	187	0	745	61	534	48	100	0	745
Gwynedd	Garth	814	Conwy	Arfon	0	0	0	125	111	0	0	0	264	234	498	205	97	0	142	51	498
Gwynedd	Gerlan	1,598	Conwy	Arfon	0	474	0	438	0	0	508	0	470	0	978	146	577	0	253	0	978
Gwynedd	Glyder	1,412	Conwy	Arfon	0	153	0	409	0	0	235	0	629	0	864	196	328	0	339	0	864
Gwynedd	Hendre	976	Conwy	Arfon	0	156	0	154	0	0	301	0	297	0	598	92	345	0	160	0	598
Gwynedd	Hirael	1,070	Conwy	Arfon	0	93	217	128	0	0	139	324	191	0	654	78	176	295	102	0	654
Gwynedd	Marchog	1,755	Conwy	Arfon	0	496	0	0	303	0	667	0	0	407	1,074	214	769	0	0	90	1,074
Gwynedd	Menai (Bangor)	1,899	Conwy	Arfon	0	69	419	112	0	0	134	811	217	0	1,162	115	188	740	117	0	1,162
Gwynedd	Ogwen	1,729	Conwy	Arfon	0	0	0	-1	0	0	0	0	1,058	0	1,058	330	157	0	570	0	1,058
Gwynedd	Pentir	1,820	Conwy	Arfon	0	254	0	454	0	0	399	0	714	0	1,113	223	504	0	385	0	1,113
Gwynedd	Tregarth & Mynydd Llandygai	1,641	Conwy	Arfon	0	443	0	322	295	0	420	0	305	279	1,004	242	535	0	164	61	1,004
	Total		Conwy							3,638	9,742	7,362	6,917	5,996	33,655	9,396	12,478	6,723	3,729	1,326	33,655

The transfer table below shows the votes cast in the old seat of Conwy at the general election, as well as the total local turnout-adjusted votes. The number of votes to transfer, shown in the fourth and fifth columns, are the difference between the general and local votes. Strong parties will have votes transferred away, and weak parties will have votes transferred into them. The final column describes how votes will be transferred away from or into that party on a ward-by-ward basis. If a party is too strong, it will lose a percentage of its votes in each ward which go into that ward's transfer pool. If a party is too weak, it will gain votes from each ward's transfer pool in proportion to the number of transfer votes it needs over the whole old seat.

Party	General Election 2005 Votes	Local Election Turnout-adjusted Votes	Votes to transfer away	Votes to transfer into	Ward Transfers needed
CON	9,398	3,638	0	5,760	Transfer in 67.8% (= 5760 / 8497) of ward's transfer pool votes
LAB	12,479	9,742	0	2,737	Transfer in 32.2% (= 2737 / 8497) of ward's transfer pool votes
LIB	6,723	7,362	639	0	Transfer away 8.7% (= 639 / 7362) of ward's LIB votes
NAT	3,730	6,917	3,187	0	Transfer away 46.1% (= 3187 / 6917) of ward's NAT votes
OTH	1,327	5,996	4,669	0	Transfer away 77.9% (= 4669 / 5996) of ward's OTH votes
Total	33,657	33,655	8,497	8,497

After transfer adjustment, the totals for each party over all the wards match the general election vote in the old seat.

New seat: Arfon

District	Ward	Electorate 2005	Old Seat	New Seat	CON Votes	LAB Votes	LIB Votes	NAT Votes	OTH Votes	Total Votes
Gwynedd	Arllechwedd	1,059	Conwy	Arfon	116	55	307	167	0	648
Gwynedd	Bethel	1,051	Caernarfon	Arfon	53	88	49	432	0	625
Gwynedd	Bontnewydd	896	Caernarfon	Arfon	45	75	42	368	0	533
Gwynedd	Cadnant	1,543	Caernarfon	Arfon	209	432	194	0	80	917
Gwynedd	Cwm-y-Glo	712	Caernarfon	Arfon	0	424	0	0	0	424
Gwynedd	Deiniol	1,014	Conwy	Arfon	90	222	169	137	0	620
Gwynedd	Deiniolen	1,371	Caernarfon	Arfon	70	116	65	564	0	816
Gwynedd	Dewi	1,217	Conwy	Arfon	61	534	48	100	0	745
Gwynedd	Garth	814	Conwy	Arfon	205	97	0	142	51	498
Gwynedd	Gerlan	1,598	Conwy	Arfon	146	577	0	253	0	978
Gwynedd	Glyder	1,412	Conwy	Arfon	196	328	0	339	0	864
Gwynedd	Groeslon	1,302	Caernarfon	Arfon	66	110	61	535	0	775
Gwynedd	Hendre	976	Conwy	Arfon	92	345	0	160	0	598
Gwynedd	Hirael	1,070	Conwy	Arfon	78	176	295	102	0	654
Gwynedd	Llanberis	1,461	Caernarfon	Arfon	175	289	162	183	58	870
Gwynedd	Llanllyfni	951	Caernarfon	Arfon	37	189	35	303	0	566
Gwynedd	Llanrug	1,372	Caernarfon	Arfon	70	116	65	564	0	816
Gwynedd	Llanwnda	1,518	Caernarfon	Arfon	77	128	72	624	0	903
Gwynedd	Marchog	1,755	Conwy	Arfon	214	769	0	0	90	1,074
Gwynedd	Menai (Bangor)	1,899	Conwy	Arfon	115	188	740	117	0	1,162
Gwynedd	Menai (Caernarfon)	1,808	Caernarfon	Arfon	154	254	142	489	35	1,076
Gwynedd	Ogwen	1,729	Conwy	Arfon	330	157	0	570	0	1,058
Gwynedd	Peblig (Caernarfon)	1,550	Caernarfon	Arfon	79	131	73	637	0	922
Gwynedd	Penisarwaun	1,348	Caernarfon	Arfon	69	114	64	554	0	802
Gwynedd	Pentir	1,820	Conwy	Arfon	223	504	0	385	0	1,113
Gwynedd	Penygroes	1,387	Caernarfon	Arfon	71	117	65	570	0	825
Gwynedd	Seiont	2,391	Caernarfon	Arfon	144	877	133	222	44	1,423
Gwynedd	Talysarn	1,385	Caernarfon	Arfon	142	234	131	274	41	824
Gwynedd	Tregarth & Mynydd Llandygai	1,641	Conwy	Arfon	242	535	0	164	61	1,004
Gwynedd	Waunfawr	1,279	Caernarfon	Arfon	192	317	178	0	73	761
Gwynedd	Y Felinheli	1,669	Caernarfon	Arfon	120	715	111	0	45	993
	Total			Arfon	3,897	9,224	3,214	8,967	582	25,887

And these are the implied results for 2005 for the new seat of Arfon.