New Boundaries 2013 Calculation

This page shows the detail of the calculations performed to estimate the general election result for 2010 had the new boundaries for Paisley and Renfrew 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 2010. 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.

Due to changes in ward boundaries, some new wards are divided among several old constituencies (and sometimes in Scotland 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 closest to 2010 from the period 2007-2011. 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 results have not yet been acquired, and the implied result is still provisional and will be improved later.

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.

List of old seats forming part of Paisley and Renfrew

Old seat: Paisley and Renfrewshire South

The raw vote table shows the district council election results for all the wards in the old seat of Paisley and Renfrewshire South. The first block shows the actual results, the second block shows the turnout-adjusted results. Details of the transfer calculation are given below this table.

Old seat: Paisley and Renfrewshire South				Actual Results					Turnout-adjusted Results
District	Ward	Election Year	Electorate 2010	CON Votes	LAB Votes	LIB Votes	NAT Votes	OTH Votes	CON Votes	LAB Votes	LIB Votes	NAT Votes	OTH Votes	Total Votes
Renfrewshire	Bishopton, Bridge of Weir and Langbank [3]	2007	588	2,077	1,113	360	2,089	83	135	72	23	136	5	371
Renfrewshire	Houston, Crosslee and Linwood [2]	2007	587	1,174	2,735	384	2,325	89	65	151	21	129	5	371
Renfrewshire	Johnstone North, Kilbarchan and Lochwinnoch	2007	10,300	568	2,191	282	2,908	87	613	2,364	304	3,137	94	6,512
Renfrewshire	Johnstone South, Elderslie and Howwood	2007	13,211	571	3,401	376	2,031	395	704	4,193	464	2,504	487	8,352
Renfrewshire	Paisley East and Ralston [1]	2007	6,396	798	2,045	1,608	2,517	369	440	1,127	886	1,387	203	4,043
Renfrewshire	Paisley North West [1]	2007	6,380	546	2,544	506	1,814	461	375	1,748	348	1,246	317	4,034
Renfrewshire	Paisley South	2007	13,784	513	2,330	928	2,104	1,510	605	2,749	1,095	2,483	1,782	8,714
Renfrewshire	Paisley South West	2007	12,022	388	2,207	1,439	2,169	330	451	2,568	1,674	2,523	384	7,600
	Total		63,268						3,388	14,972	4,815	13,545	3,277	39,997

The transfer table below shows the votes cast in the old seat of Paisley and Renfrewshire South 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 2010 Votes	Local Election Turnout-adjusted Votes	Votes to transfer away	Votes to transfer into	Ward Transfers needed
CON	3,979	3,388	0	591	Transfer in 6.2% (= 591 / 9461) of ward's transfer pool votes
LAB	23,842	14,972	0	8,870	Transfer in 93.8% (= 8870 / 9461) of ward's transfer pool votes
LIB	3,812	4,815	1,003	0	Transfer away 20.8% (= 1003 / 4815) of ward's LIB votes
NAT	7,228	13,545	6,317	0	Transfer away 46.6% (= 6317 / 13545) of ward's NAT votes
OTH	1,137	3,277	2,140	0	Transfer away 65.3% (= 2140 / 3277) of ward's OTH votes
Total	39,998	39,997	9,461	9,461

Main table for Paisley and Renfrewshire South

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

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

Old seat: Paisley and Renfrewshire North

Old seat: Paisley and Renfrewshire South	Transfer-adjusted Results
District	Ward	Electorate 2010	New Seat	CON Votes	LAB Votes	LIB Votes	NAT Votes	OTH Votes	Total Votes
Renfrewshire	Bishopton, Bridge of Weir and Langbank [3]	588	Renfrewshire South and Ayrshire North	139	139	18	73	2	371
Renfrewshire	Houston, Crosslee and Linwood [2]	587	Renfrewshire South and Ayrshire North	69	215	17	69	2	371
Renfrewshire	Johnstone North, Kilbarchan and Lochwinnoch	10,300	Renfrewshire South and Ayrshire North	712	3,853	241	1,674	33	6,512
Renfrewshire	Johnstone South, Elderslie and Howwood	13,211	Renfrewshire South and Ayrshire North	803	5,677	367	1,336	169	8,352
Renfrewshire	Paisley East and Ralston [1]	6,396	Paisley and Renfrew	500	2,031	701	740	70	4,043
Renfrewshire	Paisley North West [1]	6,380	Paisley and Renfrew	429	2,555	276	665	110	4,034
Renfrewshire	Paisley South	13,784	Paisley and Renfrew	764	5,140	867	1,325	618	8,714
Renfrewshire	Paisley South West	12,022	Paisley and Renfrew	562	4,233	1,325	1,346	133	7,600
	Total	63,268		3,978	23,843	3,812	7,228	1,137	39,997

The raw vote table shows the district council election results for all the wards in the old seat of Paisley and Renfrewshire North. The first block shows the actual results, the second block shows the turnout-adjusted results. Details of the transfer calculation are given below this table.

Old seat: Paisley and Renfrewshire North				Actual Results					Turnout-adjusted Results
District	Ward	Election Year	Electorate 2010	CON Votes	LAB Votes	LIB Votes	NAT Votes	OTH Votes	CON Votes	LAB Votes	LIB Votes	NAT Votes	OTH Votes	Total Votes
Renfrewshire	Bishopton, Bridge of Weir and Langbank [1]	2007	5,288	2,077	1,113	360	2,089	83	1,274	683	221	1,281	51	3,510
Renfrewshire	Bishopton, Bridge of Weir and Langbank [2]	2007	3,168	2,077	1,113	360	2,089	83	763	409	132	768	31	2,103
Renfrewshire	Erskine and Inchinnan [1]	2007	11,321	903	3,201	484	2,609	223	914	3,242	490	2,642	226	7,514
Renfrewshire	Erskine and Inchinnan [2]	2007	1,899	903	3,201	484	2,609	223	153	544	82	443	38	1,260
Renfrewshire	Houston, Crosslee and Linwood [1]	2007	11,296	1,174	2,735	384	2,325	89	1,312	3,057	429	2,599	99	7,496
Renfrewshire	Paisley East and Ralston [2]	2007	6,396	798	2,045	1,608	2,517	369	462	1,183	930	1,456	214	4,245
Renfrewshire	Paisley North West [2]	2007	6,379	546	2,544	506	1,814	461	394	1,835	365	1,308	332	4,234
Renfrewshire	Renfrew North	2007	9,581	286	1,763	218	2,222	516	363	2,240	277	2,823	656	6,359
Renfrewshire	Renfrew South and Gallowhill	2007	10,520	291	2,348	246	2,087	511	371	2,990	313	2,658	651	6,983
	Total		65,848						6,006	16,183	3,239	15,978	2,298	43,704

The transfer table below shows the votes cast in the old seat of Paisley and Renfrewshire North 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 2010 Votes	Local Election Turnout-adjusted Votes	Votes to transfer away	Votes to transfer into	Ward Transfers needed
CON	6,381	6,006	0	375	Transfer in 4.1% (= 375 / 9163) of ward's transfer pool votes
LAB	23,613	16,183	0	7,430	Transfer in 81.1% (= 7430 / 9163) of ward's transfer pool votes
LIB	4,597	3,239	0	1,358	Transfer in 14.8% (= 1358 / 9163) of ward's transfer pool votes
NAT	8,333	15,978	7,645	0	Transfer away 47.8% (= 7645 / 15978) of ward's NAT votes
OTH	783	2,298	1,515	0	Transfer away 65.9% (= 1515 / 2298) of ward's OTH votes
Total	43,707	43,704	9,163	9,163

Main table for Paisley and Renfrewshire North

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