Exploratory data analysis is an iterative process where high level
questions lead to specific queries whose answers are examined for
interesting patterns. These in turn suggest new questions. To facilitate
this kind of exploration, we would like to provide the analyst rapid,
incremental, and reversible operations giving continuous visual feedback.
However we also need the expressive power to reorganize the data on the
fly, to juxtapose objects according to diverse criteria, and visualizations
to show relationships among properties of these different objects. In
short, we want both the ease of use of direct manipulation systems and the
power of database query systems. This need is recognized, yet in current
systems the architecture for connecting them is a feedforward batch stream
from query to visualization system, each having a separate interface.
VQE is a Visual Query Environment for expressing queries involving
navigation among multiple objects, aggregating these objects, and defining
derived attributes for them. When combined with SAGE and SageBrush for
creating visualizations, and Visage for their direct manipulation it offers:
Query expressing a join between houses, sales and buyers, and two
visualizations of the result, which is
being filtered to show only data points where the DaysOnMarket attribute is
small. See An Interactive
Visualization Environment for Data Exploration in the Papers section for more information.
- Navigation among sets of objects of different types.
- Visualization of attributes from multiple object types in a single
- UI techniques for assigning data attributes to be visualized to
- Extension of dynamic query filter techniques to control multiple objects
- Coordination among visualizations derived from different queries.
- Dynamic definition of new data attributes.
These components are illustrated in a
VQE visualization which demonstrates how
this environment is used.