1. Introduction to Information Visualization
Slavomir Petrik, Vaclav Skala
Centre of Computer Graphics and Visualization
University of West Bohemia
Plzen, Czech Republic
2007

2. Overview of the talk History of visualization
Scientific visualization vs. Information visualization
Concepts, directions and techniques of InfoVis
1D, 2D, nD techniques
Tree and graph-based vis.
Network structure vis.
Visualization in InfoVis
Interacting with visualization
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3. From single sketch to tree maps
World map with Babylon in its centre
2300 BC
(British museum)
Growing amount of information within a single image …
14th century
Roman Britain
15th century
Leonardo da Vinci
1864
Civil war
Today…
Network structure
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4. Science of visualization
Visualization of science vs. science of visualization
Scientific visualization
Direct visualization
vs.
visualization of structure
Large data
… .
Information visualization
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5. Areas of interest Still not defined precisely !
Scientific visualization
deals with direct visualization of data that have natural geometric
structure
Information visualization
deals with more abstract data represented by trees or graphs
Visual Analytics
scientific investigation of the use of visualization in sense-making
and reasoning
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6. Information visualization
Examples
Napoleon march into Russia
Charles Minard, 1861
Ptolemy world map, 150 AD
Basic concept
Information visualization
Visualization
Data description by structures
Data
acquisition
Preprocessing
enrichment, transformation
Highlight selected information
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7. Information visualization II.
1D, 2D techniques
High dimensional data
Tree-based techniques
Network visualization
Documents visualization
Visualization
Importance of colors
Focus + context
Interaction with visualization
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8. 1D techniques Linear traverse of data Table Lens Scatterplot LensBar
Rao, 1994 ( Multivariate data )
Scatterplot
Klein, 2002 ( Span Space )
LensBar
( InfoVis 1998 )
FacetMaps
( InfoVis 2006 )
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9. 2D techniques
Fit the 2nd dimension data to the first one, GIS applications
Large datasets
Healey, 1999
Enridged contour maps
van Wijk, Telea, Vis 2001
World mapper
InfoVis 2006
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10. nD techniques 2D restriction of screen Multiple views and projections
Scatterplot matrix
Cleveland, 1985
Parallel coordinates
Inselberg, 1990
… generalization:
Moustafa, Wegman, 2002
Dimensional stacking
Langton et al. 2007
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11. nD techniques II. with help of user interaction World within worlds
Feiner, 1990
Hypercell
Santos, 2002
Interactive scatterplots
Kosara, 2004
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12. nD techniques III.
multiple views and projections for dimensionality reduction
Perspective wall
Mackinlay et al. 1991
Prosection views
Furnas, 1994
Sunflower
Rose, 1999
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13. Tree-based techniques
data organized and explored via tree structure
two different views of a tree
Side view
Top view
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14. Tree-based techniques (side view)
various forms of side view
combined with user interaction to choose proper view
Cone tree
Robertson et al., 1991
... generalized by Jeong & Pang, 1998
Cylindrical tree
Dachselt, Ebert, 2001
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15. Tree-based techniques (top view)
space filling problem
Tree map
Shneiderman, 1992
Recent surveys on Tree maps:
800 files on disk
Cushion tree map
Wijk, 1999
Ordered and quantum tree map
Bederson, 2002
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16. Tree-based techniques (top view)
Bar tree +
Arc diagram
Analysis of state transition graphs
Pretorius, TVCG 2006
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17. Visualizing network structure
intended to visualize a structure of computer network
a lot of items that need to be shown in a meaningful way
closely related to graph drawing problem
H3 Directed graph in 3D hyperbolic space
Munzer, obertson et al., 1991
( video H3 )
MBone
Munzer, 1996
Radial layout
Yee, 2001
Edge bundles
Holten, 2006
Topographic vis.
Cortese, 2006
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18. Document visualization
“So much has already been written about everything
that can’t find out anything about it.”
- James Thurber ( 1961 )
Document visualization is not information retrieval
Vast document storage: www, digital libraries (structured vs. unstructured documents)
Purpose: to gain insight into content of text and text collections
Emerged at the beginning of ’90 with growing size of electronic text documents
Seesoft
Eick, 1992
Tilebar
Hearst, 1995
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19. Document visualization
growing size of documents vs. multidimensional browsing
(Wise, 1995: Visualizing non-visual)
Spire
Wise, 1995
In-Spire
Pacific Northwest National Lab.
2004
( ThemeView )
( Starlight )
( Theme river )
for temporal patterns
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20. Summary of the first part
1D techniques
2D techniques
nD techniques
Table Lens
Scatterplots
LensBar
FacetMaps
Maps with bars
Enridged contour
maps
Worldmapper
Scatterplot matrix
Parallel coords.
Dimensional
stacking
Tree-based
techniques
Network
visualization
Document
visualization
Side-view
Top-view H3
Edge bundles
MBone
Linear
nD techniques
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21. Focus & context highlighted important parts of data
put “important” into the context of the rest of data
Fisheye lens [ Furnas, 1981 ]
Depth of field
… also in scientific visualization [ Kruger, 2006 ]
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22. Visual attention Emphasizing important information
( by color, texture, depth of field )
Cognitive psychology
( perception, long term vs. short term memory )
Kosara, S-DOF, 2002, 2003
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23. Application: Software visualization
visualizing structure of software modules
Program structure
Telea, 2002
Dynamic memory allocation
Moreta, 2006
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24. Application: Material properties
visualizing mechanical properties of materials (ZCU Plzen)
attempt to visualize many information within a single picture
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25. Summary & conclusion
Overview of the former and current state of Information visualization was presented
5 main areas of research (and many derived and combined)
1D techniques
2D techniques
nD techniques
Tree and graph-based visualization
Network structure visualization
Focus & context paradigm
Real-life application: software visualization
Two future directions:
Perception and cognition studies
Large and dynamic data visualization
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26. Thank you
Actual papers and references used in this presentation can be found
in the supplementary material distributed with this presentation.
This work has been supported by the project 3DTV NoE FP6 No:
and Ministry of Education, Youth and Sports of the Czech Republic
project VIRTUAL No: 2C06002.
Slavomir Petrik, Vaclav Skala
Center of Computer Graphics and Visualization
University of West Bohemia
Plzen, Czech Republic, 2007