Geoscience Reference
In-Depth Information
5
Geovisualisation as
an Analytical Toolbox
for Discovery
Mark Gahegan
CONTENTS
Abstract ............................................................................................................................................ 97
5.1 Introduction: GeoComputation and Information Visualisation ............................................. 98
5.2 Geovisualisation for Discovery ............................................................................................ 100
5.2.1 Exploratory Visualisation, Visual Data Mining, Knowledge Discovery ................. 101
5.2.2 Definitions of Key Terms Used ................................................................................ 102
5.2.3 Genesis of Geovisualisation Systems ....................................................................... 103
5.2.4 Geovisualisation Systems ......................................................................................... 105
5.3 Decomposing the Various Aspects of a Visualisation .......................................................... 106
5.3.1 Visual Variables ........................................................................................................ 106
5.3.2 Visual Displays ......................................................................................................... 107
5.3.2.1 More Complex Visual Metaphors .............................................................. 107
5.3.2.2 Divide and Conquer versus Compositional Approaches ........................... 108
5.3.3 Animation and the Use of Interactors....................................................................... 110
5.4 Perceptual and Cognitive Issues ........................................................................................... 110
5.4.1 Visualisation Effectiveness: The Study of Cognition and Psychometrics ................ 111
5.5 Creating Useful Visualisations ............................................................................................. 111
5.5.1 Designing a Visualisation ......................................................................................... 112
5.5.2 Example of Repeated Visual Encoding for Exploration: Choropleth Mapping ....... 113
5.5.3 Generic Exploratory Visualisation Workflow .......................................................... 114
5.6 Visualisation and the Process of Discovery Science ............................................................ 115
5.7 Conclusions and Challenges in Geovisualisation ................................................................. 117
5.8 Further Readings .................................................................................................................. 119
Acknowledgements ........................................................................................................................ 119
References ...................................................................................................................................... 119
ABSTRACT
This chapter makes the case for geovisualisation (GeoViz) as a vital ally in the struggle to address
the ever-increasing data complexity that shapes contemporary geographical analysis. And since
GeoViz is promoted here as an approach for discovery science, we look at the process by which
GeoViz is applied in discovery activities and to what extent the process, experience and results
differ from other analytical approaches, such as machine learning and exploratory statistics.
The stance taken here is that GeoViz has established enough credibility and utility to be con-
sidered an equal partner in the expanding arsenal of GeoComputation (GC) techniques and that
there is by now sufficient scientific credibility and related success stories to justify this stance.
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