cogito

Software

"version 2": using wxwidgets for its GUI, xerces as its XML parser, and scons as its multi-platform build environment.
"version 1": using X Windows Motif for its GUI, bison/flex for its input, and OpenInventor for its graphics library.

Thesis title:
A New Paradigm for Exploration in Computer-Aided Visualization

Abstract:

This dissertation examines how the computer can aid the creative human endeavour which is data visualization. That computers now critically aid many fields in this way is apparent, as is evidenced by the breadth of contemporary research on this topic.

Indeed, computers have contributed widely to the whole area of data comprehension, both in performing extensive computations and in producing visual representations of the results. Computers originally aided mathematicians who could both write the instructions necessary to direct the computer and interpret the resulting numbers. Even though modern computers include advanced graphical capabilities, many issues of access still remain: the users of data visualization software systems may not be experts in any computer-related field, yet they want to see visual representations of their data which allow them insight into their problems. For example, today's mathematicians who are generally expert in exploiting computational opportunities for experimentation may lack similar experience in opportunities for visual exploration.

Of particular concern is how a computer-aided visualization tool can be designed to support the user's goal of obtaining insight. There are many visual representations for a given set of data, and different people may obtain insight from different visual representations. Selection of the ``best'' one for an individual can be exceedingly difficult, as the sheer number of possible representations may be staggering. Current software designs either recognize the possibility of overwhelming the individual and therefore employ some means of restricting the choices that the user is allowed to make, or the designs focus on providing only the raw materials necessary for constructing the representations, leaving the user unrestricted but potentially unaided in searching out the desired representation.

The novel approach developed in this dissertation adapts a genetic algorithm to provide a means for an individual to search alternative visual representations in a systematic and manageable way. Any visual representation is a combination of elements, each selected from a different component. This approach encourages the individual's creativity without restricting available choices, and leaves the task of bookkeeping to the computer.

A computer-aided visualization system which is driven by the unique preferences of each user has been developed. The efficacy of this system, cogito, is demonstrated through a software user study. From an initial specification of components and elements, the system provides a wide variety of visual representations. From within this range of available visual representations, the user pursues the goal of achieving insight by applying personal criteria for effectiveness to the iterative selection and evaluation of candidate representations.

Note: A draft copy of the dissertation is available upon request

Publications/Presentations

	D. H. Hepting, W. Cao, and R. D. Russell, An Exploratory Approach to Mathematical Visualization, Western Computer Graphics Symposium 1998, Whistler, British Columbia, April 23-26, 1998.
	1998 ASI Exchange Day Poster: under construction
	1997 ASI Exchange Day Poster: under construction
	D. H. Hepting, F. D. Fracchia, J. C. Dill, and R. D. Russell, A Personal Paradigm for Computer-Aided Visualization, Workshop on New Paradigms in Information Visualization and Manipulation, Rockville, Maryland, November 16, 1996. Held in conjunction with the ACM Conference on Information and Knowledge Management.
	D. H. Hepting, F. D. Fracchia, J. C. Dill, and R. D. Russell, Cogito: a system for computer-aided visualization, Unpublished Technical Sketch, SIGGRAPH 1996: 23rd Annual Conference on Computer Graphics and Interactive Techniques, New Orleans, 1996. Published as CMPT TR 96-02, School of Computing Science, Simon Fraser University, Burnaby, British Columbia, Canada, August 1996.