creators_name: Simpson, Edwin creators_name: Roberts, Stephen J creators_name: Smith, Arfon creators_name: Lintott, Chris type: conference_item datestamp: 2011-11-04 10:41:56 lastmod: 2012-08-07 12:24:53 metadata_visibility: show title: Bayesian Combination of Multiple, Imperfect Classifiers ispublished: pub subjects: ML subjects: app subjects: ie full_text_status: public monograph_type: working_paper pres_type: paper abstract: Classifier combination methods need to make best use of the outputs of multiple, imperfect classifiers to enable higher accuracy classifications. In many situations, such as when human decisions need to be combined, the base decisions can vary enormously in reliability. A Bayesian approach to such uncertain combination allows us to infer the differences in performance between individuals and to incorporate any available prior knowledge about their abilities when training data is sparse. In this paper we explore Bayesian classifier combination, using the computationally efficient framework of variational Bayesian inference. We apply the approach to real data from a large citizen science project, Galaxy Zoo Supernovae, and show that our method far outperforms other established approaches to imperfect decision combination. We go on to analyse the putative community structure of the decision makers, based on their inferred decision making strategies, and show that natural groupings are formed. date: 2011-12 date_type: published publisher: University of Oxford place_of_pub: Oxford pagerange: 1-8 pages: 8 event_title: NIPS 2011 event_location: Spain event_dates: December 2011 event_type: conference institution: University of Oxford refereed: TRUE citation: Simpson, Edwin and Roberts, Stephen J and Smith, Arfon and Lintott, Chris (2011) Bayesian Combination of Multiple, Imperfect Classifiers. In: NIPS 2011, December 2011, Spain. document_url: http://www.orchid.ac.uk/eprints/7/1/vbibcc_workshop.pdf document_url: http://www.orchid.ac.uk/eprints/7/4/vbibcc_workshop.pdf