I do introduce a fudge factor based on the breakdown on religious background from the 2001 census, assuming that Nationalist parties have greater support where there are more Catholics and that Unionists have more support where there are more Protestants. Of course the mapping of total population in 2001 to voters in 2011 will be less than exact; but it will go in the right direction.
The census had Derry Rural as a whole as 59% Catholic / 39% Protestant; in 2001, Nats got 57.4% and Unionists 40.9%; in 2005 it was 57.9% and 38.2%; and this year 60.8% and 36.4%. The two wards in East Londonderry together were 71%C/28%P in the census; the other four 54%C/44%P.
29% of the 2001 population were in Banagher and Claudy. I make the adjustment by calculating that since 35% of Derry Rural’s Catholics were in the two transferred wards, I should attribute the Nationalist parties’ votes accordingly, and since 21% of the DEA’s Protestants are in the two wards, I make a similar attribution for the Unionists, and then try to find a reasonable calculation for the centre parties. (Actually I have a further fudge factor which tries to account for population movement since 2001, as far as I can.)
It won’t be perfect, since this can’t allow for relative differences of popularity between Nationalist or between Unionist parties – if Banagher and Claudy are DUP strongholds, my model will be blind to that. But it’s the best I can do.
John,
I do introduce a fudge factor based on the breakdown on religious background from the 2001 census, assuming that Nationalist parties have greater support where there are more Catholics and that Unionists have more support where there are more Protestants. Of course the mapping of total population in 2001 to voters in 2011 will be less than exact; but it will go in the right direction.
The census had Derry Rural as a whole as 59% Catholic / 39% Protestant; in 2001, Nats got 57.4% and Unionists 40.9%; in 2005 it was 57.9% and 38.2%; and this year 60.8% and 36.4%. The two wards in East Londonderry together were 71%C/28%P in the census; the other four 54%C/44%P.
29% of the 2001 population were in Banagher and Claudy. I make the adjustment by calculating that since 35% of Derry Rural’s Catholics were in the two transferred wards, I should attribute the Nationalist parties’ votes accordingly, and since 21% of the DEA’s Protestants are in the two wards, I make a similar attribution for the Unionists, and then try to find a reasonable calculation for the centre parties. (Actually I have a further fudge factor which tries to account for population movement since 2001, as far as I can.)
It won’t be perfect, since this can’t allow for relative differences of popularity between Nationalist or between Unionist parties – if Banagher and Claudy are DUP strongholds, my model will be blind to that. But it’s the best I can do.