23 Nov 2014
Quite a long time ago I spent considerable hours trawling through QMRG reports that featured in old issues of Area and Transactions of the Institute of British Geographers to examine how the committee had evolved over time. In these pre R days, I assembled these into a spreadsheet (sorry!) of both the report text, and also as a timeline. You can download both of these files on the github repository.
These files have sat on my machine for years, however, I thought they would make a nice addition to the new combined QMRG and GIScRG website - Quantile. As such, I have generate a D3 timeline of the committee membership, and assembled a chronology of events - the code is also on github here.
I would not claim that this is comprehensive, and only features those entries gathered from the reports. If you were involved in the committee and are missing, or the dates are not quite correct, then let me know.
View the timeline here
21 Nov 2014
Yesterday I needed to simplify a shapefile quite substantially to get the size down enough that it could be loaded into CartoDB. Using QGIS this tended to leave sliver or gaps between polygons, but I came across Mapshaper. This is primarily a command line tool and is built on node.js. However, a web version also exists. There are a load really useful GIS functions such as simplifying, clipping, dissolve, joins and merges.
Using Mapshaper on OSX
From install to use (including node.js) was about two minutes...
After install of node.js, you need to install Mapshaper which can be done by running the following on the terminal:
npm install -g mapshaper
If you get an error about permissions when running the above, you might have to preface the command with sudo (which will ask you for a password):
sudo npm install -g mapshaper
After this you are done. In my case, I was interested in simplifying a shapefile (located in my Dropbox) which I could complete with the following command (the % are the percentage of removable points to retain). The first shapefile listed is the input, and the second the desired output.
mapshaper /Users/alex/Dropbox/US_tract_clusters_new.shp -simplify 1% -o /Users/alex/Dropbox/US_tract_clusters_new_05pct.shp
Examples of the output:
Thanks to the developers.
22 Oct 2014
Paul Longley , James Cheshire and I supervised the PhD of Chris Gale over the past couple of years who developed the 2011 Census ONS Output Area Classification.
During development, Paul and I were approached by the Greater London Authority (GLA) to develop a classification for London that mirrored earlier work completed in relation to the 2001 OAC.
The methodology and data input to this classification followed the UK OAC 2011 specification, however, the geographic extent was constrained to Greater London. The advantage of this method, over the application of UK OAC in the context of London is that the clusters formed are more sensitive to geographic context. A full methodological report is available on the GLA website.
The London Output Area Classification can be visualised on the website - loac.datashine.org.uk.
For more information about open geodemographics and to search your LOAC classification see - www.opengeodemographics.com