1. Multidimensional Visualization David Yucht ICS 280 Spring 2001

2. The Problem at Hand How do we work with the constraints of our reality (3 Spatial Dimensions + Time/Motion) in order to visualize data sets containing potentially infinite numbers of attributes (n- Space)?

3. Potential Solutions Question is moot for < 3 attributes For > 3 attributes – Use complex 2D displays – Use multiple 3D displays – Add other distinguishing image properties – Use another medium such as sound

4. Why use 3D? Utilizes all Euclidian spatial dimensions Humans have an innate ability to process 3D images quickly without much effort Images can be enriched with other properties – Time/Motion (4D) – Color – Texture – Shape

5. Problems with 3D Computationally expensive True 3D Output & Interaction requires special equipment Navigation can be difficult Data with > 3 attributes require multiple 3D images and/or additional properties Depth & Occlusion

6. Early Test Systems W. Wright: Information Animation Applications in the Capital Markets Feiner & Beshers: Worlds Within Worlds: Metaphors for Exploring n-Dimensional Virtual Worlds

7. Information Animation 4D System for visualizing financial markets Displays Equity & Bond markets in real-time Scalable from 1 stock to entire markets Allows for querying of in-depth information upon request Utilizes movement/animation to alert users to events and give a “feel” for the market

8. Information Animation (2) Animation takes advantage of human visual processing – 4 systems within visual cortex 1 handles motion 1 handles color 2 handle object form The system thus uses motion, colors, shapes, and sizes to represent information

9. Financial Properties - Equity Price Net changes (days, weeks, quarters, etc.) Trading Volume Volume at a Price Trades at bid Trades at offer

10. Financial Properties – Bond Price Net changes Trading Volume Interest Rates Yield curve (instantaneous & historical)

11. Significance of Info Animation 3D can hold 10x or more data than 2D 3D allows users to more quickly see market trends 4D allows users to examine spreads as they occur Eases interaction & dimensional transformation problems by allowing queries Avoids occlusion problem by relying on display design and image arrangement

12. n-Vision Testbed system for representing n-Dimensions Uses true 3D imaging for display & interaction – Stereoscopic shutter glasses – VR DataGlove Handles n-Space to Euclidian spatial transformation by nesting 3D images within one another

13. n-Vision (2) Does utilize motion; can be considered a 4D system Does not utilize other image properties such as texture and color to represent attributes

14. Nesting Worlds n-Vision nests multiple 3D images in order to perform dimensionality reduction; it slices away dimensions Each 3D image is displayed on top of another, with reference marks to illustrate the values where that particular slice lies Uses recursive parent-child relationships to display & control multiple images

15. The Significance of n-Vision Provides a metaphor for > 4D visualizations Sidesteps the occlusion problem with true 3D interaction – Users can grab and rearrange images – Stereoscopic images give accurate representation of depth – Provides other tools such as the dipstick and waterline to further reduce occlusion and user confusion