Individual observations by be highlighted on the parallel coordinate plot by moving the mouse over the line segment. This highlights the PCP trace across the whole plot, allowing users to identify interesting relationships in individual observation between a pair of variables (for example, an unusual, or "outlier," observation with low surface humidity but significant rainfall) or a series of variables (like a single observation that is higher than average "across the board").
Additionally, because this strumming action occurs in real time, users may be able to identify critical attribute values where significant multivariate relationship changes occur. Strumming along the temperature variable, for example, would reveal that point where there would be a binary switch in the precipitation type variable from rain to snow. This abrupt switch would be best visualized by animating each observation in sequence according to temperature while watching the locations of the observations on another (precipitation type) axis.
This mouse-over action is illustrated at left.
