Artificial reality - The Visualization of Spatial Social Structure - page 81

constraints to allow the conditions to be attained and to ensure that the final
pictures looked acceptable. 17

3.6 Population space

It is not miles or kilometers across the surface of the earth in
which these geo-political factors are arranged, but rather an

interesting - but complicated - series of topological relationships.
(McCleary, 1988, p. 148)

The very shape and layout of the cartogram is of interest even before we
begin to use it to depict other information. The population cartogram tells us a
lot about the human geography of places - how they are related to each other in
a new and intriguingly unfamiliar way (Figures 3.14 and 3.15).
The population of Britain is more drastically dominated by London than even
most human geographers would imagine. Greater London itself contains over an
eighth of the population. If Greater London is combined with those areas under
London's immediate influence in population space, we can count nearly half the
people of the island.
The areas of influence of the other great cities are clearly shown, as is the way
they compare and combine, are divided and divide space up among themselves
(Figure 3.16). The separation of Wales into North and South, and Scotland from
England, highlights divisions that are well known, but missing from conventional
depictions. 18
To make the reading of the cartogram simpler and to learn more about popula-
tion space, we can transform the major networks of infrastructure, which service
the population and along which they move, to lie upon the transformed space.
The layout and purpose of the mainline railway network (Figure 3.17) is clear on
the cartogram (Figure 3.18). It provides a series of arteries attempting to reach
all areas equitably, in accordance to their populations.
The road network of Britain is much more complex, and only the
motorways and designated main routes are shown in the illustrations drawn

17 The algorithm was published in Dorling (1996), a copy of which can be found
here on the web: http://qmrg.org.uk/files/2008/11/59-area-cartograms.pdf. Also see the website:
http://www.ncgia.ucsb.edu/projects/Cartogram_Central/ for more cartogram ephemera.
18 The use of cartograms makes some very simple mapping possible: 'Absolute numbers should
never be mapped ... when using a standard set of boundaries. To do so is grossly misleading since
large areas will automatically tend to be black. Two solutions exist:

- to standardize the data, most commonly by converting the variable to a percentage or other
ratio form;
- to transform the map base, such that the basic areas are enlarged or reduced in size so as to
represent the total numbers of people therein, then to map, say, absolute numbers of retired
people on this new base map.

... ' (Rhind, 1983, p. 187).