{"id":823558,"date":"2022-03-02T09:32:34","date_gmt":"2022-03-02T17:32:34","guid":{"rendered":"https:\/\/cm-edgetun.pages.dev\/en-us\/research\/?post_type=msr-research-item&#038;p=823558"},"modified":"2022-03-02T09:32:34","modified_gmt":"2022-03-02T17:32:34","slug":"exploiting-correlation-to-achieve-faster-learning-rates-in-low-rank-preference-bandits","status":"publish","type":"msr-research-item","link":"https:\/\/cm-edgetun.pages.dev\/en-us\/research\/publication\/exploiting-correlation-to-achieve-faster-learning-rates-in-low-rank-preference-bandits\/","title":{"rendered":"Exploiting Correlation to Achieve Faster Learning Rates in Low-Rank Preference Bandits"},"content":{"rendered":"<p>We introduce the \\emph{Correlated Preference Bandits} problem with random utility-based choice models (RUMs), where the goal is to identify the best item from a given pool of\u00a0<span id=\"MathJax-Element-1-Frame\" class=\"MathJax\" tabindex=\"0\"><span id=\"MathJax-Span-1\" class=\"math\"><span id=\"MathJax-Span-2\" class=\"mrow\"><span id=\"MathJax-Span-3\" class=\"mi\">n<\/span><\/span><\/span><\/span> items through online subsetwise preference feedback. We investigate whether models with a simple correlation structure, e.g., low rank, can result in faster learning rates. While we show that the problem can be impossible to solve for the general `low rank&#8217; choice models, faster learning rates can be attained assuming more structured item correlations. In particular, we introduce a new class of \\emph{Block-Rank} based RUM model, where the best item is shown to be\u00a0<span id=\"MathJax-Element-2-Frame\" class=\"MathJax\" tabindex=\"0\"><span id=\"MathJax-Span-4\" class=\"math\"><span id=\"MathJax-Span-5\" class=\"mrow\"><span id=\"MathJax-Span-6\" class=\"mo\">(<\/span><span id=\"MathJax-Span-7\" class=\"mi\">\u03f5<\/span><span id=\"MathJax-Span-8\" class=\"mo\">,<\/span><span id=\"MathJax-Span-9\" class=\"mi\">\u03b4<\/span><span id=\"MathJax-Span-10\" class=\"mo\">)<\/span><\/span><\/span><\/span>-PAC learnable with only\u00a0<span id=\"MathJax-Element-3-Frame\" class=\"MathJax\" tabindex=\"0\"><span id=\"MathJax-Span-11\" class=\"math\"><span id=\"MathJax-Span-12\" class=\"mrow\"><span id=\"MathJax-Span-13\" class=\"mi\">O<\/span><span id=\"MathJax-Span-14\" class=\"mo\">(<\/span><span id=\"MathJax-Span-15\" class=\"mi\">r<\/span><span id=\"MathJax-Span-16\" class=\"msubsup\"><span id=\"MathJax-Span-17\" class=\"mi\">\u03f5<\/span><span id=\"MathJax-Span-18\" class=\"texatom\"><span id=\"MathJax-Span-19\" class=\"mrow\"><span id=\"MathJax-Span-20\" class=\"mo\">\u2212<\/span><span id=\"MathJax-Span-21\" class=\"mn\">2<\/span><\/span><\/span><\/span><span id=\"MathJax-Span-22\" class=\"mi\">log<\/span><span id=\"MathJax-Span-23\" class=\"mo\"><\/span><span id=\"MathJax-Span-24\" class=\"mo\">(<\/span><span id=\"MathJax-Span-25\" class=\"mi\">n<\/span><span id=\"MathJax-Span-26\" class=\"texatom\"><span id=\"MathJax-Span-27\" class=\"mrow\"><span id=\"MathJax-Span-28\" class=\"mo\">\/<\/span><\/span><\/span><span id=\"MathJax-Span-29\" class=\"mi\">\u03b4<\/span><span id=\"MathJax-Span-30\" class=\"mo\">)<\/span><span id=\"MathJax-Span-31\" class=\"mo\">)<\/span><\/span><\/span><\/span>\u00a0samples. This improves on the standard sample complexity bound of\u00a0<span id=\"MathJax-Element-4-Frame\" class=\"MathJax\" tabindex=\"0\"><span id=\"MathJax-Span-32\" class=\"math\"><span id=\"MathJax-Span-33\" class=\"mrow\"><span id=\"MathJax-Span-34\" class=\"texatom\"><span id=\"MathJax-Span-35\" class=\"mrow\"><span id=\"MathJax-Span-36\" class=\"munderover\"><span id=\"MathJax-Span-37\" class=\"mi\">O<\/span><span id=\"MathJax-Span-38\" class=\"mo\">~<\/span><\/span><\/span><\/span><span id=\"MathJax-Span-39\" class=\"mo\">(<\/span><span id=\"MathJax-Span-40\" class=\"mi\">n<\/span><span id=\"MathJax-Span-41\" class=\"msubsup\"><span id=\"MathJax-Span-42\" class=\"mi\">\u03f5<\/span><span id=\"MathJax-Span-43\" class=\"texatom\"><span id=\"MathJax-Span-44\" class=\"mrow\"><span id=\"MathJax-Span-45\" class=\"mo\">\u2212<\/span><span id=\"MathJax-Span-46\" class=\"mn\">2<\/span><\/span><\/span><\/span><span id=\"MathJax-Span-47\" class=\"mi\">log<\/span><span id=\"MathJax-Span-48\" class=\"mo\"><\/span><span id=\"MathJax-Span-49\" class=\"mo\">(<\/span><span id=\"MathJax-Span-50\" class=\"mn\">1<\/span><span id=\"MathJax-Span-51\" class=\"texatom\"><span id=\"MathJax-Span-52\" class=\"mrow\"><span id=\"MathJax-Span-53\" class=\"mo\">\/<\/span><\/span><\/span><span id=\"MathJax-Span-54\" class=\"mi\">\u03b4<\/span><span id=\"MathJax-Span-55\" class=\"mo\">)<\/span><span id=\"MathJax-Span-56\" class=\"mo\">)<\/span><\/span><\/span><\/span>\u00a0known for the usual learning algorithms which might not exploit the item-correlations (<span id=\"MathJax-Element-5-Frame\" class=\"MathJax\" tabindex=\"0\"><span id=\"MathJax-Span-57\" class=\"math\"><span id=\"MathJax-Span-58\" class=\"mrow\"><span id=\"MathJax-Span-59\" class=\"mi\">r<\/span><span id=\"MathJax-Span-60\" class=\"mo\">\u226a<\/span><span id=\"MathJax-Span-61\" class=\"mi\">n<\/span><\/span><\/span><\/span>). We complement the above sample complexity with a matching lower bound (up to logarithmic factors), justifying the tightness of our analysis. Surprisingly, we also show a lower bound of\u00a0<span id=\"MathJax-Element-6-Frame\" class=\"MathJax\" tabindex=\"0\"><span id=\"MathJax-Span-62\" class=\"math\"><span id=\"MathJax-Span-63\" class=\"mrow\"><span id=\"MathJax-Span-64\" class=\"mi\">\u03a9<\/span><span id=\"MathJax-Span-65\" class=\"mo\">(<\/span><span id=\"MathJax-Span-66\" class=\"mi\">n<\/span><span id=\"MathJax-Span-67\" class=\"msubsup\"><span id=\"MathJax-Span-68\" class=\"mi\">\u03f5<\/span><span id=\"MathJax-Span-69\" class=\"texatom\"><span id=\"MathJax-Span-70\" class=\"mrow\"><span id=\"MathJax-Span-71\" class=\"mo\">\u2212<\/span><span id=\"MathJax-Span-72\" class=\"mn\">2<\/span><\/span><\/span><\/span><span id=\"MathJax-Span-73\" class=\"mi\">log<\/span><span id=\"MathJax-Span-74\" class=\"mo\"><\/span><span id=\"MathJax-Span-75\" class=\"mo\">(<\/span><span id=\"MathJax-Span-76\" class=\"mn\">1<\/span><span id=\"MathJax-Span-77\" class=\"texatom\"><span id=\"MathJax-Span-78\" class=\"mrow\"><span id=\"MathJax-Span-79\" class=\"mo\">\/<\/span><\/span><\/span><span id=\"MathJax-Span-80\" class=\"mi\">\u03b4<\/span><span id=\"MathJax-Span-81\" class=\"mo\">)<\/span><span id=\"MathJax-Span-82\" class=\"mo\">)<\/span><\/span><\/span><\/span>\u00a0when the learner is forced to play just duels instead of larger subsetwise queries. Further, we extend the results to a more general `\\emph{noisy Block-Rank}&#8217; model, which ensures robustness of our techniques. Overall, our results justify the advantage of playing subsetwise queries over pairwise preferences\u00a0<span id=\"MathJax-Element-7-Frame\" class=\"MathJax\" tabindex=\"0\"><span id=\"MathJax-Span-83\" class=\"math\"><span id=\"MathJax-Span-84\" class=\"mrow\"><span id=\"MathJax-Span-85\" class=\"mo\">(<\/span><span id=\"MathJax-Span-86\" class=\"mi\">k<\/span><span id=\"MathJax-Span-87\" class=\"mo\">=<\/span><span id=\"MathJax-Span-88\" class=\"mn\">2<\/span><span id=\"MathJax-Span-89\" class=\"mo\">)<\/span><\/span><\/span><\/span>, we show the latter provably fails to exploit correlation.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>We introduce the \\emph{Correlated Preference Bandits} problem with random utility-based choice models (RUMs), where the goal is to identify the best item from a given pool of\u00a0n items through online subsetwise preference feedback. We investigate whether models with a simple correlation structure, e.g., low rank, can result in faster learning rates. While we show that [&hellip;]<\/p>\n","protected":false},"featured_media":0,"template":"","meta":{"msr-url-field":"","msr-podcast-episode":"","msrModifiedDate":"","msrModifiedDateEnabled":false,"ep_exclude_from_search":false,"_classifai_error":"","msr-author-ordering":null,"msr_publishername":"","msr_publisher_other":"","msr_booktitle":"","msr_chapter":"","msr_edition":"","msr_editors":"","msr_how_published":"","msr_isbn":"","msr_issue":"","msr_journal":"","msr_number":"","msr_organization":"","msr_pages_string":"","msr_page_range_start":"","msr_page_range_end":"","msr_series":"","msr_volume":"","msr_copyright":"","msr_conference_name":"AISTATS 2022","msr_doi":"","msr_arxiv_id":"","msr_s2_paper_id":"","msr_mag_id":"","msr_pubmed_id":"","msr_other_authors":"","msr_other_contributors":"","msr_speaker":"","msr_award":"","msr_affiliation":"","msr_institution":"","msr_host":"","msr_version":"","msr_duration":"","msr_original_fields_of_study":"","msr_release_tracker_id":"","msr_s2_match_type":"","msr_citation_count_updated":"","msr_published_date":"2022-2-23","msr_highlight_text":"","msr_notes":"","msr_longbiography":"","msr_publicationurl":"","msr_external_url":"","msr_secondary_video_url":"","msr_conference_url":"","msr_journal_url":"","msr_s2_pdf_url":"","msr_year":0,"msr_citation_count":0,"msr_influential_citations":0,"msr_reference_count":0,"msr_s2_match_confidence":0,"msr_microsoftintellectualproperty":true,"msr_s2_open_access":false,"msr_s2_author_ids":[],"msr_pub_ids":[],"msr_hide_image_in_river":0,"footnotes":""},"msr-research-highlight":[],"research-area":[13556],"msr-publication-type":[193716],"msr-publisher":[],"msr-focus-area":[],"msr-locale":[268875],"msr-post-option":[],"msr-field-of-study":[246694,246685],"msr-conference":[],"msr-journal":[],"msr-impact-theme":[],"msr-pillar":[],"class_list":["post-823558","msr-research-item","type-msr-research-item","status-publish","hentry","msr-research-area-artificial-intelligence","msr-locale-en_us","msr-field-of-study-artificial-intelligence","msr-field-of-study-machine-learning"],"msr_publishername":"","msr_edition":"","msr_affiliation":"","msr_published_date":"2022-2-23","msr_host":"","msr_duration":"","msr_version":"","msr_speaker":"","msr_other_contributors":"","msr_booktitle":"","msr_pages_string":"","msr_chapter":"","msr_isbn":"","msr_journal":"","msr_volume":"","msr_number":"","msr_editors":"","msr_series":"","msr_issue":"","msr_organization":"","msr_how_published":"","msr_notes":"","msr_highlight_text":"","msr_release_tracker_id":"","msr_original_fields_of_study":"","msr_download_urls":"","msr_external_url":"","msr_secondary_video_url":"","msr_longbiography":"","msr_microsoftintellectualproperty":1,"msr_main_download":"","msr_publicationurl":"","msr_doi":"","msr_publication_uploader":[{"type":"url","viewUrl":"false","id":"false","title":"https:\/\/arxiv.org\/abs\/2202.11795","label_id":"243109","label":0}],"msr_related_uploader":"","msr_citation_count":0,"msr_citation_count_updated":"","msr_s2_paper_id":"","msr_influential_citations":0,"msr_reference_count":0,"msr_arxiv_id":"","msr_s2_author_ids":[],"msr_s2_open_access":false,"msr_s2_pdf_url":null,"msr_attachments":[],"msr-author-ordering":[{"type":"text","value":"Suprovat Ghoshal","user_id":0,"rest_url":false},{"type":"user_nicename","value":"Aadirupa Saha","user_id":39835,"rest_url":"https:\/\/cm-edgetun.pages.dev\/en-us\/research\/wp-json\/microsoft-research\/v1\/researchers?person=Aadirupa Saha"}],"msr_impact_theme":[],"msr_research_lab":[199571],"msr_event":[821218],"msr_group":[],"msr_project":[],"publication":[],"video":[],"msr-tool":[],"msr_publication_type":"inproceedings","related_content":[],"_links":{"self":[{"href":"https:\/\/cm-edgetun.pages.dev\/en-us\/research\/wp-json\/wp\/v2\/msr-research-item\/823558","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/cm-edgetun.pages.dev\/en-us\/research\/wp-json\/wp\/v2\/msr-research-item"}],"about":[{"href":"https:\/\/cm-edgetun.pages.dev\/en-us\/research\/wp-json\/wp\/v2\/types\/msr-research-item"}],"version-history":[{"count":1,"href":"https:\/\/cm-edgetun.pages.dev\/en-us\/research\/wp-json\/wp\/v2\/msr-research-item\/823558\/revisions"}],"predecessor-version":[{"id":823561,"href":"https:\/\/cm-edgetun.pages.dev\/en-us\/research\/wp-json\/wp\/v2\/msr-research-item\/823558\/revisions\/823561"}],"wp:attachment":[{"href":"https:\/\/cm-edgetun.pages.dev\/en-us\/research\/wp-json\/wp\/v2\/media?parent=823558"}],"wp:term":[{"taxonomy":"msr-research-highlight","embeddable":true,"href":"https:\/\/cm-edgetun.pages.dev\/en-us\/research\/wp-json\/wp\/v2\/msr-research-highlight?post=823558"},{"taxonomy":"msr-research-area","embeddable":true,"href":"https:\/\/cm-edgetun.pages.dev\/en-us\/research\/wp-json\/wp\/v2\/research-area?post=823558"},{"taxonomy":"msr-publication-type","embeddable":true,"href":"https:\/\/cm-edgetun.pages.dev\/en-us\/research\/wp-json\/wp\/v2\/msr-publication-type?post=823558"},{"taxonomy":"msr-publisher","embeddable":true,"href":"https:\/\/cm-edgetun.pages.dev\/en-us\/research\/wp-json\/wp\/v2\/msr-publisher?post=823558"},{"taxonomy":"msr-focus-area","embeddable":true,"href":"https:\/\/cm-edgetun.pages.dev\/en-us\/research\/wp-json\/wp\/v2\/msr-focus-area?post=823558"},{"taxonomy":"msr-locale","embeddable":true,"href":"https:\/\/cm-edgetun.pages.dev\/en-us\/research\/wp-json\/wp\/v2\/msr-locale?post=823558"},{"taxonomy":"msr-post-option","embeddable":true,"href":"https:\/\/cm-edgetun.pages.dev\/en-us\/research\/wp-json\/wp\/v2\/msr-post-option?post=823558"},{"taxonomy":"msr-field-of-study","embeddable":true,"href":"https:\/\/cm-edgetun.pages.dev\/en-us\/research\/wp-json\/wp\/v2\/msr-field-of-study?post=823558"},{"taxonomy":"msr-conference","embeddable":true,"href":"https:\/\/cm-edgetun.pages.dev\/en-us\/research\/wp-json\/wp\/v2\/msr-conference?post=823558"},{"taxonomy":"msr-journal","embeddable":true,"href":"https:\/\/cm-edgetun.pages.dev\/en-us\/research\/wp-json\/wp\/v2\/msr-journal?post=823558"},{"taxonomy":"msr-impact-theme","embeddable":true,"href":"https:\/\/cm-edgetun.pages.dev\/en-us\/research\/wp-json\/wp\/v2\/msr-impact-theme?post=823558"},{"taxonomy":"msr-pillar","embeddable":true,"href":"https:\/\/cm-edgetun.pages.dev\/en-us\/research\/wp-json\/wp\/v2\/msr-pillar?post=823558"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}