{"id":"https://openalex.org/W4285410129","doi":"https://doi.org/10.1145/3532213.3532255","title":"Hierarchical Portfolios in Recommender Ecosystems","display_name":"Hierarchical Portfolios in Recommender Ecosystems","publication_year":2022,"publication_date":"2022-03-18","ids":{"openalex":"https://openalex.org/W4285410129","doi":"https://doi.org/10.1145/3532213.3532255"},"language":"en","primary_location":{"id":"doi:10.1145/3532213.3532255","is_oa":false,"landing_page_url":"https://doi.org/10.1145/3532213.3532255","pdf_url":null,"source":null,"license":null,"license_id":null,"version":"publishedVersion","is_accepted":true,"is_published":true,"raw_source_name":"Proceedings of the 8th International Conference on Computing and Artificial Intelligence","raw_type":"proceedings-article"},"type":"conference-paper","indexed_in":["crossref"],"open_access":{"is_oa":false,"oa_status":"closed","oa_url":null,"any_repository_has_fulltext":false},"authorships":[{"author_position":"first","author":{"id":"https://openalex.org/A5041386867","display_name":"\u0160t\u011bp\u00e1n Balcar","orcid":"https://orcid.org/0000-0001-6614-2595"},"institutions":[{"id":"https://openalex.org/I21250087","display_name":"Charles University","ror":"https://ror.org/024d6js02","country_code":"CZ","type":"education","lineage":["https://openalex.org/I21250087"]}],"countries":["CZ"],"is_corresponding":false,"raw_author_name":"Stepan Balcar","raw_affiliation_strings":["Faculty of Mathematics and Physics, Charles University, Czech Republic"],"raw_orcid":null,"affiliations":[{"raw_affiliation_string":"Faculty of Mathematics and Physics, Charles University, Czech Republic","institution_ids":["https://openalex.org/I21250087"]}]},{"author_position":"middle","author":{"id":"https://openalex.org/A5008815142","display_name":"Ladislav Pe\u0161ka","orcid":"https://orcid.org/0000-0001-8082-4509"},"institutions":[{"id":"https://openalex.org/I21250087","display_name":"Charles University","ror":"https://ror.org/024d6js02","country_code":"CZ","type":"education","lineage":["https://openalex.org/I21250087"]}],"countries":["CZ"],"is_corresponding":false,"raw_author_name":"Ladislav Peska","raw_affiliation_strings":["Faculty of Mathematics and Physics, Charles University, Czech Republic"],"raw_orcid":null,"affiliations":[{"raw_affiliation_string":"Faculty of Mathematics and Physics, Charles University, Czech Republic","institution_ids":["https://openalex.org/I21250087"]}]},{"author_position":"last","author":{"id":"https://openalex.org/A5023733020","display_name":"Peter Vojt\u00e1\u0161","orcid":"https://orcid.org/0000-0002-3526-8475"},"institutions":[{"id":"https://openalex.org/I21250087","display_name":"Charles University","ror":"https://ror.org/024d6js02","country_code":"CZ","type":"education","lineage":["https://openalex.org/I21250087"]}],"countries":["CZ"],"is_corresponding":false,"raw_author_name":"Peter Vojtas","raw_affiliation_strings":["Faculty of Mathematics and Physics, Charles University, Czech Republic"],"raw_orcid":null,"affiliations":[{"raw_affiliation_string":"Faculty of Mathematics and Physics, Charles University, Czech Republic","institution_ids":["https://openalex.org/I21250087"]}]}],"institutions":[],"countries_distinct_count":1,"institutions_distinct_count":1,"corresponding_author_ids":[],"corresponding_institution_ids":["https://openalex.org/I21250087"],"apc_list":null,"apc_paid":null,"fwci":null,"has_fulltext":false,"cited_by_count":0,"citation_normalized_percentile":null,"cited_by_percentile_year":null,"biblio":{"volume":"2","issue":null,"first_page":"280","last_page":"285"},"is_retracted":false,"is_paratext":false,"is_xpac":false,"primary_topic":{"id":"https://openalex.org/T10203","display_name":"Recommender Systems and Techniques","score":0.9995999932289124,"subfield":{"id":"https://openalex.org/subfields/1710","display_name":"Information Systems"},"field":{"id":"https://openalex.org/fields/17","display_name":"Computer Science"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}},"topics":[{"id":"https://openalex.org/T10203","display_name":"Recommender Systems and Techniques","score":0.9995999932289124,"subfield":{"id":"https://openalex.org/subfields/1710","display_name":"Information Systems"},"field":{"id":"https://openalex.org/fields/17","display_name":"Computer Science"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}},{"id":"https://openalex.org/T13274","display_name":"Expert finding and Q&A systems","score":0.951200008392334,"subfield":{"id":"https://openalex.org/subfields/1710","display_name":"Information Systems"},"field":{"id":"https://openalex.org/fields/17","display_name":"Computer Science"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}},{"id":"https://openalex.org/T12101","display_name":"Advanced Bandit Algorithms Research","score":0.9417999982833862,"subfield":{"id":"https://openalex.org/subfields/1803","display_name":"Management Science and Operations Research"},"field":{"id":"https://openalex.org/fields/18","display_name":"Decision Sciences"},"domain":{"id":"https://openalex.org/domains/2","display_name":"Social Sciences"}}],"keywords":[{"id":"https://openalex.org/keywords/recommender-system","display_name":"Recommender system","score":0.7511109709739685},{"id":"https://openalex.org/keywords/computer-science","display_name":"Computer science","score":0.5989727973937988},{"id":"https://openalex.org/keywords/ecosystem","display_name":"Ecosystem","score":0.553507387638092},{"id":"https://openalex.org/keywords/information-retrieval","display_name":"Information retrieval","score":0.252360463142395},{"id":"https://openalex.org/keywords/ecology","display_name":"Ecology","score":0.1446971893310547},{"id":"https://openalex.org/keywords/biology","display_name":"Biology","score":0.08226889371871948}],"concepts":[{"id":"https://openalex.org/C557471498","wikidata":"https://www.wikidata.org/wiki/Q554950","display_name":"Recommender system","level":2,"score":0.7511109709739685},{"id":"https://openalex.org/C41008148","wikidata":"https://www.wikidata.org/wiki/Q21198","display_name":"Computer science","level":0,"score":0.5989727973937988},{"id":"https://openalex.org/C110872660","wikidata":"https://www.wikidata.org/wiki/Q37813","display_name":"Ecosystem","level":2,"score":0.553507387638092},{"id":"https://openalex.org/C23123220","wikidata":"https://www.wikidata.org/wiki/Q816826","display_name":"Information retrieval","level":1,"score":0.252360463142395},{"id":"https://openalex.org/C18903297","wikidata":"https://www.wikidata.org/wiki/Q7150","display_name":"Ecology","level":1,"score":0.1446971893310547},{"id":"https://openalex.org/C86803240","wikidata":"https://www.wikidata.org/wiki/Q420","display_name":"Biology","level":0,"score":0.08226889371871948}],"mesh":[],"locations_count":1,"locations":[{"id":"doi:10.1145/3532213.3532255","is_oa":false,"landing_page_url":"https://doi.org/10.1145/3532213.3532255","pdf_url":null,"source":null,"license":null,"license_id":null,"version":"publishedVersion","is_accepted":true,"is_published":true,"raw_source_name":"Proceedings of the 8th International Conference on Computing and Artificial Intelligence","raw_type":"proceedings-article"}],"best_oa_location":null,"sustainable_development_goals":[],"awards":[],"funders":[],"has_content":{"grobid_xml":false,"pdf":false},"content_urls":null,"referenced_works_count":17,"referenced_works":["https://openalex.org/W1549854018","https://openalex.org/W2032383746","https://openalex.org/W2086045598","https://openalex.org/W2296428656","https://openalex.org/W2406582849","https://openalex.org/W2609787396","https://openalex.org/W2753328553","https://openalex.org/W2790360016","https://openalex.org/W2896432580","https://openalex.org/W2911936302","https://openalex.org/W2912500072","https://openalex.org/W3006895932","https://openalex.org/W3038620866","https://openalex.org/W3103067638","https://openalex.org/W3124153368","https://openalex.org/W4252407093","https://openalex.org/W4287721425"],"related_works":["https://openalex.org/W4391375266","https://openalex.org/W2748952813","https://openalex.org/W4390273403","https://openalex.org/W4386781444","https://openalex.org/W2150182025","https://openalex.org/W3092950680","https://openalex.org/W3197542405","https://openalex.org/W2056712470","https://openalex.org/W3125580266","https://openalex.org/W4317039510"],"abstract_inverted_index":{"This":[0],"paper":[1,66],"focuses":[2],"on":[3,151],"the":[4,8,32,68,76,83,101,125,155],"recommendation":[5,77],"problem":[6,78],"from":[7,154],"perspective":[9],"of":[10,17,22,27,49,64,70,85,98,103,118,133,157],"hierarchical":[11,72,93,126],"heterogeneous":[12],"portfolios.":[13],"These":[14],"portfolios":[15,91,160,164],"consist":[16],"several":[18],"base":[19,40,104,169],"recommenders.":[20],"Each":[21],"them":[23],"processes":[24],"different":[25,36],"subset":[26],"available":[28],"data":[29,153],"and":[30,44,79,114],"achieves":[31],"best":[33],"performance":[34,56],"under":[35],"circumstances.":[37],"By":[38],"running":[39],"recommenders":[41,170],"in":[42,82],"parallel":[43],"employing":[45],"a":[46,71,115,130],"suitable":[47],"aggregation":[48,102],"their":[50],"results":[51],"(i.e.":[52],"ensemble":[53,73],"approach)":[54],"considerable":[55],"gains":[57],"can":[58],"be":[59],"achieved.":[60],"The":[61],"main":[62],"contribution":[63],"this":[65],"is":[67],"proposal":[69],"approach":[74],"to":[75,92,141],"its":[80],"utilization":[81],"case":[84],"repeated":[86],"recommendations.":[87],"We":[88],"extend":[89],"flat":[90,163],"ones":[94],"with":[95,108],"two":[96],"levels":[97],"aggregation.":[99],"For":[100],"recommenders,":[105],"we":[106,128],"experimented":[107],"Thompson":[109],"sampling":[110],"multi-armed":[111],"bandits":[112],"algorithm":[113],"modified":[116,131],"version":[117,132],"D\u2019Hondt\u2019s":[119],"mandates":[120],"allocation":[121,136],"algorithm.":[122],"As":[123],"for":[124],"aggregation,":[127],"implemented":[129],"D21-Janecek":[134],"mandate":[135],"algorithm,":[137],"which":[138],"allows":[139],"us":[140],"incorporate":[142],"implicit":[143],"negative":[144],"feedback":[145],"as":[146,165,167],"well.":[147],"Experiments":[148],"were":[149],"performed":[150],"real-world":[152],"domain":[156],"e-commerce.":[158],"Hierarchical":[159],"outperformed":[161],"both":[162],"well":[166],"individual":[168],"w.r.t.":[171],"click-through":[172],"rate.":[173]},"counts_by_year":[],"updated_date":"2026-07-14T23:27:15.235271","created_date":"2025-10-10T00:00:00"}