Task Abstraction in Visualization: Actions and Targets
Task Abstraction: Why?
Chapter 3
Actions
- Analyze:
- Consume: Analyzing existing information without creating new data.
- Discover: Uncover new insights or analyze information that is not readily apparent.
- Present: Share knowledge with others.
- Enjoy: Explore data for personal satisfaction.
- Produce: Generating new material.
- Annotate: Add extra information to highlight important data points.
- Record: Capture and save data.
- Derive: Create new data based on existing data.
- Consume: Analyzing existing information without creating new data.
- Query: How to examine the target
- Identify: Refer to a single target.
- Compare: Refer to multiple targets.
- Summarize: Refer to the full set of possible targets.
Targets
- All data
- Trend: Identify increases, decreases, and peaks.
- Outliers: Discover data points that deviate significantly from the norm.
- Features: Discover all elements not classified as trends or outliers.
- Attributes
- One:
- Distribution: Analyze the spread of data.
- Extremes: Identify maximum and minimum values.
- Many:
- Dependency: Explore relationships between attributes.
- Correlation: Measure the strength and direction of relationships.
- Similarity: Identify attributes with similar patterns.
- One:
- Network data
- Topology: Analyze the structure and connections within the network.
- Path: Find the shortest or most efficient route between nodes.
- Topology: Analyze the structure and connections within the network.
- Spatial data
- Shape: Analyze the form and outline of spatial objects.
Task Abstractions: Actions
First, we need to analyze tasks abstractly. Transforming task descriptions from domain-specific language into abstract forms allows you to reason about similarities and differences between them. When analyzing, we need to consider who has a goal or makes a design choice: the designer of the visualization or the end-user.
To analyze why a visualization tool is being used, we need to break down the reasons into actions and targets.
Three levels of actions:
- Highest-level: Analyze, consume, or produce information.
- Consume: Present, discover, and enjoy. Discovery may involve generating or verifying a hypothesis.
- Produce: Annotate, record, and derive.
- Middle-level: Search. Search can be classified according to whether the identity and location of targets are known or not:
- Lookup: Both identity and location are known.
- Locate: The target is known, but its location is not.
- Browse: The location is known, but the target is not.
- Explore: Neither the target nor the location is known.
- Low-level: Query. Queries can have three scopes:
- Identify one target.
- Compare some targets.
- Summarize all targets.
Task Abstractions: Targets
These are the parts of the data that the targets find relevant.
- All Data: Generally speaking, a user’s concerns may include identifying patterns, trends, and outliers.
- Attributes: An individual may be interested in studying the following:
- Single attribute (to simulate its distribution)
- Multiple attributes (to simulate their relationships).
- Spatial Data: An individual may be interested in learning about objects’ shapes.
- Network Data: A user would be curious to learn about its topology, or connection patterns.
Abstractions
- Rule of thumb: Eliminate any domain jargon in a systematic way.
- Interplay: Data abstraction must be used within task abstraction.
- However, task abstraction can cause you to repeatedly change the data.
Means and Ends
- Ends, or goals, are what we aim to do, and means are what we use to achieve those goals.
- {action, target} pairings: Find outliers, compare trends, learn about distribution, browse topology.
Why is Validation Difficult?
Chapter 4
There are different ways to get it wrong at each level:
We need to pick methods from different fields at each level. The solutions for each level are:
- Algorithm: Doing computational benchmarks to measure system time and memory. Analyze computational complexity (technique-driven work).
- Visual encoding (design level): Justify the design with respect to alternatives, then analyze results qualitatively (cognitive psychology) and conduct lab studies.
- Data/task abstraction: Observing people after deployment (field study); lab studies are not sufficient.
- Domain situation: Observing people using existing tools.
Notes:
- Lab studies do not confirm task abstraction.
- Computational benchmarks do not confirm idiom design.