In a nod to my colleague James Cheshire‘s fascination with cartograms, I’ve created one from the Spatial Equity data I used in the previous post. A cartogram is a map in which the value of each spatial unit’s area is replaced with a thematic mapping value; thus the mapped representation is warped and distorted to reflect the new thematic variable. Danny Dorling has been particularly active in this field, writing up work on Dorling Cartograms in the CATMOG series, and laterly using the Gastner Newman method to create cartograms for his interesting work in the book: The Atlas of the Real World.
Figure 1: Cartogram of Spatial Equity by Gravity Potential Model
It is clear from figure 1 that the south of Southwark suffers in terms of accessibility to a Southwark GP, whereas the central areas, characterised by a higher population density and more social housing have greater accessibility to healthcare services.
Whilst I’m not sure whether such a representation is entirely appropriate in this context, it does tell an interesting story- the same as the previous post but in a different manner, using the size of areas as well.
NB the map is subject to Crown Copyright 2009 Ordnance Survey. An UKBorders/JISC supplied service.
December 10th, 2009
by danny
Is the map still subject to Crown Copyright 2009 Ordnance Survey aka “An UKBorders/JISC supplied service” even after you’ve made it interesting and stretched it? I think you shoudl donate it to the world – or at least the people of Southwark – lovely map! danny
December 11th, 2009
by Dan
The Author
I’m using the outline of Southwark from UK borders as a reference to contrast the cartogram with the real-world geography. This element is definitely subject to crown copyright. As to whether the Cartogram is – pass. Better safe than sorry though!