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ORCID

https://orcid.org/0000-0002-6658-9749

Access Type

Campus-Only Access for Five (5) Years

Document Type

thesis

Embargo Period

9-1-2020

Degree Program

Psychology

Degree Type

Master of Science (M.S.)

Year Degree Awarded

2020

Month Degree Awarded

September

Abstract

An ensemble representation refers to a statistical summary representation of a group of similar objects. Recent work has shown that we can form multiple ensemble representations – ensemble representations for a single feature dimension across multiple stimulus groups, ensemble representations for multiple feature dimensions in the same stimulus group, and ensemble representations across multiple sensory domains. In our study, we use hierarchical stimuli based on the Navon figures (Navon 1977) to study properties of ensemble representations across multiple spatial scales. In Experiments 1 and 3, we study properties of ensemble representations for the orientation and size feature dimension, respectively. In Experiment 2, we study properties of individual representations for the orientation feature dimension. Results indicate that it is possible to form ensemble representations across multiple spatial scales. Experiment 1 shows that the global ensemble representations may be extracted automatically (without intent) whereas the local ensemble representation is only extracted in response to task demands (with intent). Finally, in both Experiment 1 and Experiment 3, participants were more accurate at reporting the global ensemble representation than the local ensemble representation whereas in Experiment 2, performance did not differ across the levels. These results point towards global precedence in the formation of ensemble representations.

DOI

https://doi.org/10.7275/17657230

First Advisor

Kyle Cave

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