Reading focus
Syllabus: How Do We Organize Knowledge?
Return to typicality with categories whose members may share a purpose rather than a familiar label. Compare graded judgments with evidence that category links are already established in memory.
A question to consider. For a category such as things to take on a rainy walk, what would distinguish a shared typicality ordering from fast, familiar access to its members?
Why this reading
Some categories exist because of what someone is trying to do. Barsalou investigates whether such categories have typical and atypical members even when their links in memory are weak. This separates a category's graded structure from how familiar or established it is.
Before you read
An ad hoc category is assembled for a particular purpose and is not yet well established in memory. A goal-derived category can become familiar through repeated use. Graded structure means that members differ in how good an example they seem. Distinguish generating examples from a label, recalling studied items, and finding a label for a set of objects: these tasks test different directions of access.
Read for
- Compare typicality judgments with measures of how readily people generate and remember members. Similar graded structure need not imply equally accessible knowledge.
- Follow the comparison between labeling item sets with and without a goal-relevant context.
- Separate experimental evidence about the chosen categories from the proposed processes by which a new category could become established through use.
Consider afterwards
- Choose four unlike objects that would help achieve one everyday goal. What would count as evidence that people share a category for them, rather than merely understand the goal after you explain it?
Editorial context
The paper extends categorization research beyond familiar taxonomies using several tasks and selected goal-related categories. Its findings do not imply that every temporary grouping has the same structure or that all goal-derived categories remain ad hoc. Some developmental and learning proposals in the discussion go beyond the experiments reported. The distinction between graded judgments and established memory organization is the enduring explanatory issue.