[OSGeo Africa] Comparing census and elections datasets

[Adi Eyal]

Thanks Hanlie and Charles

Sounds like that's the only way to go. I was hoping that secretly,
StatsSA was remapping census data to various shapefiles. Charles,
happy to take a crack at it with you to try to develop a script that
will allow this remapping across different boundaries.

Adi

On 9 April 2014 10:14, Charles Rethman <rethman at me.com> wrote:
> Dear Adi and everybody,
>
> I've been thinking about this. I think whatever happens you'll need to do
> some cookie-cutting.
>
> The best solution I think would be to make your algorithm in PostGIS and map
> it on QGIS.
>
> If you like, we could meet up and discuss the details further--and post our
> trials or results back to this forum? Where--Codebridge? contact me on
> rethman at me.com.
>
> Charles Rethman
> Wahenga Ltd.
> Director, Cape Town Office
>
> Cell: +27 71 6735502
> Tel: +27 21 6861510
> Skype: cwrethman
> PO Box 23507, Claremont, 7735, South Africa
> 19 Sans Souci Road, Newlands, 7700, Cape Town
>
>
> On 8 Apr 2014, at 7:12 AM, Adi Eyal <adi at code4sa.org> wrote:
>
> Hi All
>
> I would like map demographic data from the 2011 census on top of
> elections results from 2009. There seem to be two problems with doing
> this.
>
> 1. Old wards have disappeared and new ones have been created by MDB.
> 2. In some cases the same ward id has been re-used for completely
> different polygons.
>
> In short, the obvious approach of joining two datasets won't work. It
> is possible (but difficult) to calculate approximations by overlapping
> shapes from the two maps and using some sort of algorithm (possibly
> assuming uniform distribution of data points) to slice up one shape
> and fit it into another.
>
> I don't want to go down that route.
>
> Is there another to go about this?
>
> Thanks
> Adi
>
> --
> Adi Eyal
> Director
> Code for South Africa
> Promoting informed decision-making
>
> phone: +27 78 014 2469
> skype: adieyalcas
> linkedin: http://za.linkedin.com/pub/dir/Adi/Eyal
> web: http://www.code4sa.org
> twitter: @soapsudtycoon
>
> For more information on how to participate in the open data community
> in South Africa, go to: http://www.code4sa.org/#community
> _______________________________________________
> Africa mailing list
> Africa at lists.osgeo.org
> You can UNSUBSCRIBE at http://lists.osgeo.org/mailman/listinfo/africa
>
>
>
> _______________________________________________
> Africa mailing list
> Africa at lists.osgeo.org
> You can UNSUBSCRIBE at http://lists.osgeo.org/mailman/listinfo/africa



-- 
Adi Eyal
Director
Code for South Africa
Promoting informed decision-making

phone: +27 78 014 2469
skype: adieyalcas
linkedin: http://za.linkedin.com/pub/dir/Adi/Eyal
web: http://www.code4sa.org
twitter: @soapsudtycoon

For more information on how to participate in the open data community
in South Africa, go to: http://www.code4sa.org/#community