Visualization Analysis and Design

Chapter 4

Analysis: Four Levels for Validation

4.1 The Big Picture

Figure 4.1 shows four nested levels of design: domain situation, task and data abstraction, visual encoding and interaction idiom, and algorithm. The task and data abstraction level addresses the why and what questions, and the idiom level addresses the question of how. Each of these levels has different threats to validity, so it’s a good idea to choose your validation method with these levels in mind.

Figure 4.1.

The four nested levels of vis design have different threats to validity at each level, and validation approaches should be chosen accordingly.

4.2 Why Validate?