Selection: 524,288 ways to say "this is interesting"

Visualization is a critical technology for understanding complex, data-rich systems. Effective visualizations make important features of the data immediately recognizable and enable the user to discover interesting and useful results by highlighting patterns. A key element of such systems is the ability to interact with displays of data by selecting a subset for further investigation. This operation is needed for use in linked-views systems and in drill-down analysis. It is a common manipulation in many other systems. It is as ubiquitous as selecting icons in a desktop GUI. It is therefore surprising to note that little research has been done on how selection can be implemented. This paper addresses this omission, presenting a taxonomy for selection mechanisms and discussing the interactions between branches of the taxonomy. Our suggestion of 524,288 possible systems [2/sup 16/ operation systems/spl times/2 (memory/memoryless)/spl times/2 (data-dependent/independent)/spl times/2 (brush/lasso)] is more in fun than serious, as within the taxonomy there are many different choices that can be made. This framework is the result of considering both the current state of the art and historical antecedents.