Indirect Multi-Touch Interaction for Brushing in Parallel Coordinates

Interaction in visualization is often complicated and tedious. Brushing data in a visualization such as parallel coordinates is a central part of the data analysis process, and sets visualization apart from static charts. Modifying a brush, or combining it with another one, usually requires a lot of effort and mode switches, though, slowing down interaction and even discouraging more complex questions. We propose the use of multi-touch interaction to provide fast and convenient interaction with parallel coordinates. By using a multi-touch trackpad rather than the screen directly, the user's hands do not obscure the visualization during interaction. Using one, two, three, or four fingers, the user can easily and quickly perform complex selections. Being able to change the selections rapidly, the user can explore the data set more easily and effectively, and can focus on the data rather than the interaction.