Information Visualization Chapter 1 - Continued
Reference Model Visualization: Mapping from data to visual form Raw DataData Tables Visual Structures Views Data Transformations Visual Mappings View Transformations DATAVISUAL FORM Human Interaction
Data Tables Relational descriptions of data extended to include metadata CaseiCasejCasek VariablexValueixValuejxValuekx… VariableyValueiyValuejyValueky… …………… Analogy to database: Variable -> attribute; Case -> tuple or record
Data Tables (2) Variable Types N = Nominal Unordered set O = Ordinal Ordered set Q = Quantitative Numeric range Metadata Structure
Data Transformations Values Derived Values Structure Derived Structure Values Derived Structure Structure Derived Values Examples?
Visual Structures Data Tables are mapped to Visual Structures Expressive, effective Perception…and the human eye…
Visual Structures (2) Spatial substrates Marks Graphical properties
Spatial Substrate Space is the container unto which other parts of Visual Structure are poured. Composition Alignment Folding Recursion Overloading
Marks Points Lines Areas Volumes Graphs and Trees – to show relations or links among objects
Retinal Properties Type of graphical property Position/Size Gray Scale Orientation Color Texture Shape
Other Graphical Properties Crispness Resolution Transparency Arrangement Color: value, hue, saturation Table 1.22 Finally, temporal encoding for visual structures
View Transformations Interactively modify and augment Visual Structures Location Probes Viewpoint Controls Zoom, pan, clip Overview an detail Distortions To perceive larger Visual Structure via distortion
Human Interaction and Transformation Direct Manipulation Controlling Mappings
Conclusion Reference model approximates the basic steps for visualizing information Steps are an ongoing process with many iterations Goal of information visualization: develop effective mappings to increase ability to think/to improve cognition