Geography Reference
In-Depth Information
for example, is accessed by more than 2,000 users every day, and the numbers are
growing, especially for very simple choropleth maps. Already Arnberger (
1977
)
expressed, what is still true today: “The majority of thematic maps are justifiably of
analytical nature”, which is often the “best and only possible way of expression.”
Reference Areas
Reference areas—variously shaped polygons in maps to which thematic data is
attributed—are an important part of the base map in any thematic map—and
probably the most important feature in statistical maps that otherwise do not
show many situational elements (apart from borders and bodies of water). Statisti-
cal maps are characterised by two kinds of reference areas. The most common class
and almost a “natural” basis are administrative divisions. Rarely,
non-administrative divisions (geometric, geographic or value area surfaces) can
be found.
It is a fact in geographic science: existing administrative areas are very hetero-
geneous in size and structure and therefore not suited for geographical analysis.
Yet, official statistics, due to their existing survey methods and their political
mandate,
1
are generally unable to go beyond the representation of administrative
boundaries. Table
3
shows that 96.2 % of all maps in statistical atlases still refer to
this area type or its aggregates. Also 96 % of the maps published by the Swiss FSO
are based on administrative divisions. Although often asked for, there is no visible
trend towards the use of more geographic or geometric units.
Table
4
shows the average distribution of the various spatial divisions in
statistical maps. Almost 35 % of the maps correspond to the NUTS 3 level (cantons
in Switzerland, districts in Germany, or counties in the United Kingdom). A similar
share goes to maps based on communes. Higher or lower hierarchical levels are
either not suited for maps, or data is not available for them.
Table 3 Reference units in
statistical maps and atlases
a
Type of reference area
Share
Administrative
96.2 %
Non-administrative
Geometric
3.2 %
Geographical
0.2 %
Statistical reliefs
0.4 %
a
Based on the analysis of 20 atlases and 6,500 maps (Schulz
2013
)
1
Statistical laws or decrees often explicitly demand data by the NSIs on administrative levels, such
as states, cantons, districts, municipalities or communes.
