[DDI-users] Defining political parties as DDI categories

[Humphrey Southall]

Although we cannot quite make a public announcement, the GB 
Historical Project has major new funding covering mapping British 
electoral units (constituencies) over the last 150 years and using 
these to present detailed parliamentary election results over that 
period.  That means listing the number of votes for each political 
party in each constituency in each election.

Our system for holding statistical data is very much based around the 
DDI, but so far has been used mainly to store and present either 
aggregate census or vital registration data.  See:

	http://www.ddialliance.org/codebook/projects.html#britain

Has anyone experience of using the DDI with electoral statistics?

I know that in principle we should define a new variable for each set 
of parties that get listed, so that for example the results for 
constituencies in which these parties stood:

	Conservative
	Labour
	Liberal Democrat

... would be different from this:

	Conservative
	Labour
	Liberal Democrat
	Scottish Nationalist

However, this would mean that our system could not present any 
national maps or time series graphs.  Is there any fundamental 
objection to defining a single variable which includes ALL the 
parties who ever stood in British election over the last 150 years?

Best wishes,

Humphrey Southall
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    ====================================
Humphrey Southall
Reader in Geography/Director,
Great Britain Historical GIS Project
Department of Geography, University of Portsmouth
Buckingham Building, Lion Terrace, Portsmouth PO1 3HE

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