the two measures country by country. Thus our
approach seems perform chloropleth multimaps.
To conclude, our geovisualization methods based
on chorems do not always replace classical
geovisualization methods of SOLAP tools, but they
appear useful when dealing with phenomena that can
be represented as chorems.
However, usability test should be provided to
quantify the advantage of using chorem maps
instead of SOLAP maps. They represent our future
work.
6 CONCLUSIONS AND FUTURE
WORK
SOLAP systems allow decision-makers to on-line
explore warehoused spatial data by means of
SOLAP operators, which aggregate numerical
indicators, to produce reports composed of pivot
tables, graphical displays and thematic maps.
However, when the analysed spatial phenomena are
complex, advanced geovisualization techniques are
need. On the other hand, it has been recently shown
that chorem maps represent an excellent
geovisualzation technique to summarize and reveal
hidden spatial phenomena. However, chorem
systems are based on pre-defined maps, which limit
potentiality of spatial decision-making process.
Thus, the goal of this paper is to introduce a
framework being capable to merge the interactive
analysis capability of SOLAP systems and the
potentiality of a chorem-based visual notation in
terms of visual summary.
In detail, we propose a set of methods to on-line
extract and visualize chorems on the top of a SDW.
We also propose an implementation of our
framework using a general architecture based on
standards.
As future work, we plan to investigate other
chorems as defined in (Lardon et al., 2005). We also
plan to define a usability study to evaluate in a
quantitative way the pro and cons of the usage of
chorems instead of classical SOLAP
geovisualization methods from a visualization point
of view.
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