The latest outputs from researchers, alumni and friends at the UCL Centre for Advanced Spatial Analysis (CASA).
The purpose of map generalisation is to represent spatial data in a way that makes it possible to effectively view the data at scales smaller than that for which it was originally intended. In the case of the Ordnance Survey’s MasterMap product you have data at an incredibly fine level of spatial resolution, which is […]
Continue reading »I work a lot with flows and spatial interactions, one thing that I’ve wanted to do for a while is compute a mean flow direction surface. Unfortunately, arithmetic means don’t work for angular data, this is because it cannot account for the circular nature of the distribution of angular measurements. For instance the angles 5 […]
Continue reading »The intent of this post is not simply to uncover where the highest density of people belonging to a particular ethnic group are, but rather to use the ‘location quotient’ (LQ) technique to compare the ethnic density in any one area to the overall ethnic density in Southwark, thus providing a relative insight into where […]
Continue reading »Using the excellent SANET extension for ArcGIS 9.3 I was able to take some of my data for Southwark that I had geocoded to address level, and estimate the population density using the OS Mastermap ITN product. The procedure is essentially a Kernel Density Estimation that takes place on a given network rather than across 2D space, this effectively controls […]
Continue reading »I saw a thought provoking presentation recently, given by Wenwen Li of the University of California Santa Barbara, the talk was a wide ranging insight into Cyber Infrastructure, its uses for geospatial information, and some of the computational techniques that underpinned the project. One element of the project involved zone design for the greater Los […]
Continue reading »I liked Ben Hennig’s population cartogram of the UK under snow, but I thought it could perhaps show something a little more serious than simply where the people are. To do this I went to the UK Census 2001 (I know, an old data source, but the only thing I was aware of that could […]
Continue reading »A subtitle to this post might also be: Are we all being mislead by the New York Times? In stating this I am referring to the recent maps released by the New York Times looking at ethnic distributions from the US Census Bureau’s American Community Survey. The most immediate thing we can learn about this […]
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