Showing papers by "Barbara Tversky published in 2001"

Event structure in perception and conception.

Abstract: Events can be understood in terms of their temporal structure. The authors first draw on several bodies of research to construct an analysis of how people use event structure in perception, understanding, planning, and action. Philosophy provides a grounding for the basic units of events and actions. Perceptual psychology provides an analogy to object perception: Like objects, events belong to categories, and, like objects, events have parts. These relationships generate 2 hierarchical organizations for events: taxonomies and partonomies. Event partonomies have been studied by looking at how people segment activity as it happens. Structured representations of events can relate partonomy to goal relationships and causal structure; such representations have been shown to drive narrative comprehension, memory, and planning. Computational models provide insight into how mental representations might be organized and transformed. These different approaches to event structure converge on an explanation of how multiple sources of information interact in event perception and conception.

Perceiving, remembering, and communicating structure in events

Abstract: How do people perceive routine events, such as making a bed, as these events unfold in time? Research on knowledge structures suggests that people conceive of events as goal-directed partonomic hierarchies. Here, participants segmented videos of events into coarse and fine units on separate viewings; some described the activity of each unit as well. Both segmentation and descriptions support the hierarchical bias hypothesis in event perception: Observers spontaneously encoded the events in terms of partonomic hierarchies. Hierarchical organization was strengthened by simultaneous description and, to a weaker extent, by familiarity. Describing from memory rather than perception yielded fewer units but did not alter the qualitative nature of the descriptions. Although the descriptions were telegraphic and without communicative intent, their hierarchical structure was evident to naive readers. The data suggest that cognitive schemata mediate between perceptual and functional information about events and indicate that these knowledge structures may be organized around object/action units.

Mental spatial transformations of objects and perspective

Abstract: This study sought evidence for the independence of two classes of mental spatial transformation: object-based spatial transformations and egocentric perspective transformations Two tasks were designed to selectively elicit these two transformations using the same materials, participants, and task parameters: one required same-different judgments about pairs of pictures, while the other required left-right judgments about single pictures For pictures of human bodies, the two tasks showed strikingly different patterns of response time as a function of stimulus orientation Moreover, across individuals, the two tasks had different relationships to psychometric tests of spatial ability The chronometric and individual difference data converge with neuropsychological and neuroimaging data in suggesting that different mental spatial transformations are performed by dissociable neural systems

Seeing into sketches: regrouping parts encourages new interpretations

Abstract: One surprising benefit of sketches is the insights they provide to the sketcher. Sketches are ambiguous, allowing even their creators to reinterpret them, a process more difficult to do in the mind. How is it that sketchers can see new things in their own sketches? One possibility is that they regroup the parts into new wholes, with different meanings. A protocol analyses of an experienced architect confirmed this hypothesis: regrouping parts of sketch drove detection of new features in sketches. Further, novices who adopted this strategy generated more interpretations of ambiguous sketches than those who didn't adopt the strategy. Regrouping seems to be a general skill for generating multiple interpretations, applicable to many kinds of sketches. Encouraging this skill should enhance design.

The (in)effectiveness of animation in instruction

Abstract: Animated graphics have been increasingly adopted to teach complex systems, encouraged by the preconception that realism is effective. Nevertheless, the evidence has been discouraging as to their effectiveness. By the Conceptual Congruence Hypothesis, graphics should be effective in conveying concepts that are literally or metaphorically spatial. By extension, animated graphics should be effective in conveying change in time. This hypothesis was investigated by comparing three interfaces that presented text, text plus static graphics, or text plus animated graphics. Evidence was obtained for the static version of the Conceptual Congruence Hypothesis. Graphics were more effective than text in some cases, especially for participants with low spatial ability, but animation did not further increase effectiveness.