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and partly because unemployment is known to vary seasonally. The images show
dramatic changes in the social structure of Britain.
Initially, in the late 1970s there was only high unemployment in an expanded
Celtic fringe, but gradually the picture changed until, by 1990, unemployment was
highest in the north and in inner cities, leaving a ring of almost full employment
around Outer London. Between those dates, at the height of the early 1980s
recession, places like Liverpool were seen to do relatively well as their positions
improved in relation to other areas, though it became worse in absolute terms.
Work such as this requires very large matrices of data, over a million rates
for the ward time series (which, as a consequence, is not visualized here). It
would perhaps be better if the fate of individuals were better known, rather than
us knowing these giant matrices of aggregate counts of people's fortunes, but
while that is all we have, we must use it. A second problem concerns the use
of deviation from the expected, to highlight change. This makes the images seen
especially dependent on the first and last years chosen to bound the study period.
In future visualizations it might be better practice to show the changes
between individual years, which would be insensitive as to which time span
was chosen. Finally, the twelve slices only begin to capture the inside-out goblet
shaped structure of spacetime regional inequality in Britain. To see it as it is,
we need software that can in a sophisticated way render a projection of a great
many observations in space - or a lot of imagination.
9.3
Spacetime continuum
If space and time are considered jointly as a three-dimensional block
of space-time with co-ordinates of time, latitude, and longitude, and if
incidence (occurrences related to the population at risk) is represented
within the volume of the block, it follows that there must be some
unevenness.
(Knox, 1964. pp. 20-21)
In some cases, usually when the information is sparse, we do have a near
complete record of individual cases. For instance, a complete list of firms open-
ing and closing, including the number of their employees could be created to
try and understand unemployment change. The situation where such information
is most plentiful is with the medical records of rare diseases. The incidences
of when these are detected are available to the level of the address of the suf-
ferer and the day of diagnosis. Such records are relatively few, allowing more
sophisticated techniques to be attempted than could be used with the voluminous
unemployment data. In Figure 9.6 each case is added to the map as a bell shaped
kernel, or cone, 6 the influence of these decaying with distance (Box 9.1) from
their incidence in both space and time.
6 The idea of representing incidents by a cone has been previously suggested: 'It may be useful
to think of total population influence in yet another way. Each person's influence may be represented
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