English
 
User Manual Privacy Policy Disclaimer Contact us
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT
  Categorisation performance depends systematically on shape transformations

Dahl, C., Graf, M., & Bülthoff, H. (2003). Categorisation performance depends systematically on shape transformations. Poster presented at 26th European Conference on Visual Perception (ECVP 2003), Paris, France.

Item is

Basic

show hide
Item Permalink: http://hdl.handle.net/11858/00-001M-0000-0013-DBC9-A Version Permalink: http://hdl.handle.net/21.11116/0000-0005-0F2D-A
Genre: Poster

Files

show Files

Locators

show
hide
Description:
-

Creators

show
hide
 Creators:
Dahl, C1, 2, 3, Author              
Graf, M2, 3, Author              
Bülthoff, HH2, 3, Author              
Affiliations:
1Department Physiology of Cognitive Processes, Max Planck Institute for Biological Cybernetics, Max Planck Society, ou_1497798              
2Department Human Perception, Cognition and Action, Max Planck Institute for Biological Cybernetics, Max Planck Society, ou_1497797              
3Max Planck Institute for Biological Cybernetics, Max Planck Society, Spemannstrasse 38, 72076 Tübingen, DE, ou_1497794              

Content

show
hide
Free keywords: -
 Abstract: The shape variability of objects from the same basic-level category can be conceptualised by transformations which continuously change object shape. Morphing between members of a basic-level category allows to systematically vary the shape of common objects. We demonstrated that categorisation performance depends on the amount of shape transformation, using a sequential matching task (Graf and Bülthoff, 2003, EuroCogSci, Osnabrück, Germany). We further investigated shape dependence of basic-level categorisation with name matching and rating tasks. We created five category members (1, 25, 50, 75, and 100 morphs) for twenty-five basic-level categories, based on morphable 3-D object models. Objects were rendered as grey-level images and presented in a canonical orientation. In the speeded name-matching experiment, subjects had to decide whether an object corresponded to a category name. In a second experiment, subjects were required to rate the typicality of the objects, ie they had to rate how well the objects corresponded to their mental image of the category. Both name-matching latencies and typicality ratings depended systematically on the amount of shape transformation. Name-matching latencies were significantly shorter for exemplars that were more in the middle of the morphing sequence. These exemplars were also rated as more typical in experiment 2. The findings confirm the systematic dependence of categorisation performance on the amount of shape transformation. Shapes that are rated as more prototypical are categorised faster. This shape-dependence in basic-level categorisation is reminiscent of the orientation-dependence in recognition, where the canonical perspective is rated as more typical and recognised faster [Palmer et al, 1981, in Attention and Performance IX Eds J Long, A Baddeley (Hillsdale, NJ: Lawrence Erlbaum Associates) pp 135 - 151]. Overall, the results support an extension of the image-based model of recognition (Bülthoff et al, 1995 Cerebral Cortex 3 297 - 260) to basic-level categorisation.

Details

show
hide
Language(s):
 Dates: 2003-09
 Publication Status: Published in print
 Pages: -
 Publishing info: -
 Table of Contents: -
 Rev. Type: -
 Identifiers: BibTex Citekey: 2417
DOI: 10.1068/ecvp03a
 Degree: -

Event

show
hide
Title: 26th European Conference on Visual Perception (ECVP 2003)
Place of Event: Paris, France
Start-/End Date: 2003-09-01 - 2003-09-05

Legal Case

show

Project information

show

Source 1

show
hide
Title: Perception
Source Genre: Journal
 Creator(s):
Affiliations:
Publ. Info: London : Pion Ltd.
Pages: - Volume / Issue: 32 (ECVP Abstract Supplement) Sequence Number: - Start / End Page: 117 - 118 Identifier: ISSN: 0301-0066
CoNE: https://pure.mpg.de/cone/journals/resource/954925509369