{"id":{"repo_id":"cape-town","oai_identifier":"oai:open.uct.ac.za:11427/29506"},"canonical_url":"https://search.dev.ndltd.org/etd/cape-town/oai:open.uct.ac.za:11427/29506","repository":{"repo_id":"cape-town","name":"University of Cape Town","base_url":"https://open.uct.ac.za/oai/request"},"display":{"title":"The butcher, the baker, the candlestick maker: investigating facial recognition for multiple-perpetrator crimes","abstract":"In the United States, 20% of all violent crime is committed by multiple perpetrators. Despite the prevalence of multiple-perpetrator crimes, most published eyewitness research uses a single-perpetrator paradigm: that is, witnesses view a crime committed by a single perpetrator whom they must recognise later. Multiple-perpetrator crimes, however, present with several problems. Police procedure for administering multiple-suspect parades is poorly defined. Furthermore, eyewitnesses must make multiple identifications, and are tasked with a unique memory problem of perpetrator-role assignment. I studied these problems in the following ways: (a) a survey among South African detectives (N = 75) to investigate how multiple suspect parades are administered in practice; (b) two face recognition experiments where the number of face-attribute pairs was manipulated at encoding to investigate the effect of set size on both item recognition (for attributes and faces), and associative memory performance (i.e., matching identity to role; N = 70, and N = 67); (c) an eyewitness experiment where participants studied a simulated crime committed by up to 10 perpetrators whom they had to recognise later (N = 200); and (d) a set of simulations testing a revised version of the Interactive Activation and Competition network proposed by Burton et al. (1990) as a computational account of the memory difficulties experienced by eyewitnesses to multiple-perpetrator crimes. Overall, the results suggest that associative memory is particularly vulnerable to the negative effects of set size, and that role-players in law and psychology should consider the implications of these difficulties in court and the laboratory.","abstract_html":"In the United States, 20% of all violent crime is committed by multiple perpetrators. Despite the prevalence of multiple-perpetrator crimes, most published eyewitness research uses a single-perpetrator paradigm: that is, witnesses view a crime committed by a single perpetrator whom they must recognise later. Multiple-perpetrator crimes, however, present with several problems. Police procedure for administering multiple-suspect parades is poorly defined. Furthermore, eyewitnesses must make multiple identifications, and are tasked with a unique memory problem of perpetrator-role assignment. I studied these problems in the following ways: (a) a survey among South African detectives (N = 75) to investigate how multiple suspect parades are administered in practice; (b) two face recognition experiments where the number of face-attribute pairs was manipulated at encoding to investigate the effect of set size on both item recognition (for attributes and faces), and associative memory performance (i.e., matching identity to role; N = 70, and N = 67); (c) an eyewitness experiment where participants studied a simulated crime committed by up to 10 perpetrators whom they had to recognise later (N = 200); and (d) a set of simulations testing a revised version of the Interactive Activation and Competition network proposed by Burton et al. (1990) as a computational account of the memory difficulties experienced by eyewitnesses to multiple-perpetrator crimes. Overall, the results suggest that associative memory is particularly vulnerable to the negative effects of set size, and that role-players in law and psychology should consider the implications of these difficulties in court and the laboratory.","abstract_has_math":false,"creators":["Nortje, Alicia"],"institution":"Department of Psychology","degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":["Tredoux, Colin","Vredeveldt, Annelies"],"committee_chairs":[],"committee_members":[],"year":2018,"date_issued":"2018","date_published":"2018","updated_at":"2026-07-22T22:22:46Z","subjects":[],"languages":["eng"],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"http://hdl.handle.net/11427/29506","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.advisor","label":"Advisor","values":["Tredoux, Colin","Vredeveldt, Annelies"]},{"key":"dc:creator","label":"Author","values":["Nortje, Alicia"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2019-02-13T13:09:16Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2019-02-13T13:09:16Z"]},{"key":"dc:date.issued","label":"Date","values":["2018"]},{"key":"dc:publisher.department","label":"Dc Publisher Department","values":["Department of Psychology"]},{"key":"dc:publisher.institution","label":"Dc Publisher Institution","values":["University of Cape Town"]},{"key":"dc:type","label":"Dc Type","values":["Doctoral Thesis"]},{"key":"dc:type.qualificationlevel","label":"Dc Type Qualificationlevel","values":["Doctoral"]},{"key":"dc:type.qualificationname","label":"Dc Type Qualificationname","values":["PhD"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language.iso","label":"Language (ISO)","values":["eng"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["http://hdl.handle.net/11427/29506"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["In the United States, 20% of all violent crime is committed by multiple perpetrators. Despite the prevalence of multiple-perpetrator crimes, most published eyewitness research uses a single-perpetrator paradigm: that is, witnesses view a crime committed by a single perpetrator whom they must recognise later. Multiple-perpetrator crimes, however, present with several problems. Police procedure for administering multiple-suspect parades is poorly defined. Furthermore, eyewitnesses must make multiple identifications, and are tasked with a unique memory problem of perpetrator-role assignment. I studied these problems in the following ways: (a) a survey among South African detectives (N = 75) to investigate how multiple suspect parades are administered in practice; (b) two face recognition experiments where the number of face-attribute pairs was manipulated at encoding to investigate the effect of set size on both item recognition (for attributes and faces), and associative memory performance (i.e., matching identity to role; N = 70, and N = 67); (c) an eyewitness experiment where participants studied a simulated crime committed by up to 10 perpetrators whom they had to recognise later (N = 200); and (d) a set of simulations testing a revised version of the Interactive Activation and Competition network proposed by Burton et al. (1990) as a computational account of the memory difficulties experienced by eyewitnesses to multiple-perpetrator crimes. Overall, the results suggest that associative memory is particularly vulnerable to the negative effects of set size, and that role-players in law and psychology should consider the implications of these difficulties in court and the laboratory."]},{"key":"dc:title","label":"Title","values":["The butcher, the baker, the candlestick maker: investigating facial recognition for multiple-perpetrator crimes"]}]}],"canonical_facts":{"dc:contributor.advisor":["Tredoux, Colin","Vredeveldt, Annelies"],"dc:creator":["Nortje, Alicia"],"dc:date.accessioned":["2019-02-13T13:09:16Z"],"dc:date.available":["2019-02-13T13:09:16Z"],"dc:date.issued":["2018"],"dc:description.abstract":["In the United States, 20% of all violent crime is committed by multiple perpetrators. Despite the prevalence of multiple-perpetrator crimes, most published eyewitness research uses a single-perpetrator paradigm: that is, witnesses view a crime committed by a single perpetrator whom they must recognise later. Multiple-perpetrator crimes, however, present with several problems. Police procedure for administering multiple-suspect parades is poorly defined. Furthermore, eyewitnesses must make multiple identifications, and are tasked with a unique memory problem of perpetrator-role assignment. I studied these problems in the following ways: (a) a survey among South African detectives (N = 75) to investigate how multiple suspect parades are administered in practice; (b) two face recognition experiments where the number of face-attribute pairs was manipulated at encoding to investigate the effect of set size on both item recognition (for attributes and faces), and associative memory performance (i.e., matching identity to role; N = 70, and N = 67); (c) an eyewitness experiment where participants studied a simulated crime committed by up to 10 perpetrators whom they had to recognise later (N = 200); and (d) a set of simulations testing a revised version of the Interactive Activation and Competition network proposed by Burton et al. (1990) as a computational account of the memory difficulties experienced by eyewitnesses to multiple-perpetrator crimes. Overall, the results suggest that associative memory is particularly vulnerable to the negative effects of set size, and that role-players in law and psychology should consider the implications of these difficulties in court and the laboratory."],"dc:identifier.uri":["http://hdl.handle.net/11427/29506"],"dc:language.iso":["eng"],"dc:publisher.department":["Department of Psychology"],"dc:publisher.institution":["University of Cape Town"],"dc:title":["The butcher, the baker, the candlestick maker: investigating facial recognition for multiple-perpetrator crimes"],"dc:type":["Doctoral Thesis"],"dc:type.qualificationlevel":["Doctoral"],"dc:type.qualificationname":["PhD"]},"updated_at":"2026-07-22T22:22:46Z"}