creators_name: Edelman, Shimon creators_name: Cutzu, Florin creators_name: Duvdevani-Bar, Sharon type: preprint datestamp: 1997-11-17 lastmod: 2011-03-11 08:54:04 metadata_visibility: show title: Similarity, Connectionism, and the Problem of Representation in Vision subjects: cog-psy full_text_status: public abstract: We present a unified approach to visual representation, addressing both the needs of superordinate and basic-level categorization and of identification of specific instances of familiar categories. According to the proposed theory, a shape is represented by its similarity to a number of reference shapes, measured in a high-dimensional space of elementary features. This amounts to embedding the stimulus in a low-dimensional proximal shape space. That space turns out to support representation of distal shape similarities which is veridical in the sense of Shepard's (1968) notion of second-order isomorphism (i.e., correspondence between distal and proximal similarities among shapes, rather than between distal shapes and their proximal representations). Furthermore, a general expression for similarity between two stimuli, based on comparisons to reference shapes, can be used to derive models of perceived similarity ranging from continuous, symmetric, and hierarchical, as in the multidimensional scaling models (R. N. Shepard, 1980), to discrete and non-hierarchical, as in the general contrast models (A. Tversky, 1977; R. N. Shepard and P. Arabie, 1979). date: 1996 date_type: published refereed: FALSE citation: Edelman, Shimon and Cutzu, Florin and Duvdevani-Bar, Sharon (1996) Similarity, Connectionism, and the Problem of Representation in Vision. [Preprint] document_url: http://cogprints.org/568/1/199711002.ps