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At the
time when this study was undertaken, the Department of Environment (DoE) was much more
concerned with urban deprivation, and especially inner city regeneration. In 1975
Sally Holtermann, then a researcher within the DoE, also noticed the ratio bias. She
pointed out that if area targeting is seen to be efficient, effective and equitable, then
the metrics used should identify areas, where- a high proportion of the local population is deprived
(ratios)
- a high proportion of all deprived live (numbers)
- there is a high density of deprived in the area
(for cost effective action) |
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| As we have already
noted, ratios and numbers operationalise only one each of the above requirements. The
question is how do we accommodate all these three requirements simultaneously? This
was a common problem and there were a variety of graphical solutions, which were not
entirely satisfactory.
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For
example, Professor Howe, in his 1970 Atlas of Disease and Mortality used :
- Proportional symbols for the number of deaths
- Shading to indicate the Standardised Mortality Ratios. He also used dotted outlines when
these ratios were statistically insignificant.
The map becomes cluttered and confusing and it is difficult to discern the more
important trends. The shading (here the ratios) tends to dominate. |
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