This article provides a description of animated brushing in the interactive graph module.

 

Typical applications of animated brushing are in exploratory data analysis using matrix plots, where instead of brushing consecutive ranges of a variable (to explore the influence of various sections of its distribution), an automatic movement of the brush (Box, Lasso, Slice X, Slice Y, Slice Z, or Cube) can be invoked while watching the "results."

Specifically, a brushing region is defined in one subgraph in the matrix and is automatically moved across the subgraph (horizontally, vertically, or both). As the brushing region passes over groups of points in the subplot, corresponding points in all other plots are highlighted.

For example, in the illustration below, the rectangular region can be advanced automatically across groups of points in the Income, and the corresponding points will be highlighted in plots of the other three variables. The speed and direction of the movement can be interactively controlled in the Animation dialog.

The Animate button is available on the Interactive tab of the Brushing dialog whenever the Draggable Brush check box is marked and the Box, Lasso, Cube, Slice X, Slice Y, or Slice Z brush is selected.

Draggable brush. A user-controlled animation. Note that when the Draggable Brush check box is selected on the Interactive tab of the Brushing dialog, you can select cases via any of the six shape defining brushing tools (i.e., Box, Lasso, Cube, Slice X, Slice Y, or Slice Z), and then drag that shape to any position on the graph, thus animating the selection manually. Note that the Draggable Brush check box must be selected before you make your selection in order to use the animated brushing facilities described above.