Categorization of partially occluded visual stimuli: bridging the gap between completion and classification

Peer reviewed: 
No, item is not peer reviewed.
Date created: 
2009
Keywords: 
Visual perception
Categorization (Psychology)
Categorization
Visual cognition
Visual completion
Object recognition
Occlusion
Missing information
Abstract: 

Many current models of categorization assume full knowledge of the properties of the stimulus to be categorized. To remedy this situation, it is first necessary to understand how humans categorize stimuli with missing information. To that end, two visual category learning experiments were conducted using an inverse base-rate effect paradigm. In the second experiment, transfer trials included stimuli in which a category-diagnostic present/absent feature was occluded. Response proportions showed that people tend to treat occluded features as being absent from the stimulus, suggesting a more general tendency to assign default values to features of unknown status at the time of categorization. This pattern of results could not be replicated by several computational models – EXIT, SUSTAIN, or EXALT, a modification of EXIT implementing additive similarity.

Language: 
English
Document type: 
Thesis
Rights: 
Copyright remains with the author. The author granted permission for the file to be printed, but not for the text to be copied and pasted.
File(s): 
Senior supervisor: 
M
Department: 
Dept. of Psychology - Simon Fraser University
Thesis type: 
Thesis (M.A.)
Statistics: