{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/92989"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/92989","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"Parallel processing of efficient, heterogeneous visual search with real-world objects","abstract":"Previous work in our lab has demonstrated that efficient visual search has a reaction time by set size function that is best characterized by logarithmic curves, and the steepness of these logarithmic curves is determined by the similarity between target and distractor items (Buetti et al., in press). This thesis presents a theoretical account of these phenomena, emphasizing that a parallel, unlimited capacity, exhaustive processing system must be underlying such data. Two experiments were conducted to expand our findings to a set of real-world stimuli, in both homogeneous and heterogeneous search displays. Based on our current theory and numerical simulations, we were able to very accurately predict RT performance in heterogeneous search using parameters from homogeneous search tasks of a different group of subjects. By examining the systematic deviation of our predictions from observed data, we concluded that early visual processing for individual items were not independent. Instead, items in homogeneous displays seemed to facilitate each other's processing by a multiplicative factor. These results challenge previous accounts of heterogeneity effects in visual search, and demonstrate the explanatory and predictive power of our current theory of visual search.","abstract_html":"Previous work in our lab has demonstrated that efficient visual search has a reaction time by set size function that is best characterized by logarithmic curves, and the steepness of these logarithmic curves is determined by the similarity between target and distractor items (Buetti et al., in press). This thesis presents a theoretical account of these phenomena, emphasizing that a parallel, unlimited capacity, exhaustive processing system must be underlying such data. Two experiments were conducted to expand our findings to a set of real-world stimuli, in both homogeneous and heterogeneous search displays. Based on our current theory and numerical simulations, we were able to very accurately predict RT performance in heterogeneous search using parameters from homogeneous search tasks of a different group of subjects. By examining the systematic deviation of our predictions from observed data, we concluded that early visual processing for individual items were not independent. Instead, items in homogeneous displays seemed to facilitate each other's processing by a multiplicative factor. These results challenge previous accounts of heterogeneity effects in visual search, and demonstrate the explanatory and predictive power of our current theory of visual search.","abstract_has_math":false,"creators":["Wang, Zhiyuan"],"institution":"University of Illinois at Urbana-Champaign","degree_name":"M.A.","degree_level":"Thesis","degree_discipline":"Psychology","degree_department":null,"school":null,"contributors":["Lleras, Alejandro"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2016,"date_issued":"2016-11-10T18:38:57Z","date_published":"2016-11-10T18:38:57Z","updated_at":"2026-07-22T22:26:35Z","subjects":["visual search","parallel processing","heterogeneity","logarithmic"],"languages":["en"],"rights":["Copyright 2016 Zhiyuan Wang"],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"http://hdl.handle.net/2142/92989","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Lleras, Alejandro"]},{"key":"dc:creator","label":"Author","values":["Wang, Zhiyuan"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2016-11-10T18:38:57Z","2018-11-11T10:15:11Z","2016-05-12","2016-08"]},{"key":"dc:type","label":"Dc Type","values":["text"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Psychology"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Thesis"]},{"key":"thesis:degree_name","label":"Degree Name","values":["M.A."]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["University of Illinois at Urbana-Champaign"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["visual search","parallel processing","heterogeneity","logarithmic"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["en"]},{"key":"dc:rights","label":"Dc Rights","values":["Copyright 2016 Zhiyuan Wang"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["http://hdl.handle.net/2142/92989"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Previous work in our lab has demonstrated that efficient visual search has a reaction time by set size function that is best characterized by logarithmic curves, and the steepness of these logarithmic curves is determined by the similarity between target and distractor items (Buetti et al., in press). 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These results challenge previous accounts of heterogeneity effects in visual search, and demonstrate the explanatory and predictive power of our current theory of visual search.","Submission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2018-08-01","The student, Zhiyuan Wang, accepted the attached license on 2016-05-11 at 16:59.","The student, Zhiyuan Wang, submitted this Thesis for approval on 2016-05-11 at 17:10.","This Thesis was approved for publication on 2016-05-12 at 15:19.","DSpace SAF Submission Ingestion Package generated from Vireo submission #9606 on 2016-11-10 at 12:23:56","Made available in DSpace on 2016-11-10T18:38:57Z (GMT). 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These results challenge previous accounts of heterogeneity effects in visual search, and demonstrate the explanatory and predictive power of our current theory of visual search.","Submission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2018-08-01","The student, Zhiyuan Wang, accepted the attached license on 2016-05-11 at 16:59.","The student, Zhiyuan Wang, submitted this Thesis for approval on 2016-05-11 at 17:10.","This Thesis was approved for publication on 2016-05-12 at 15:19.","DSpace SAF Submission Ingestion Package generated from Vireo submission #9606 on 2016-11-10 at 12:23:56","Made available in DSpace on 2016-11-10T18:38:57Z (GMT). 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