{"id":"https://openalex.org/W2591674748","doi":"https://doi.org/10.1145/3027385.3029469","title":"Buying time","display_name":"Buying time","publication_year":2017,"publication_date":"2017-02-27","ids":{"openalex":"https://openalex.org/W2591674748","doi":"https://doi.org/10.1145/3027385.3029469","mag":"2591674748"},"language":"en","primary_location":{"id":"doi:10.1145/3027385.3029469","is_oa":false,"landing_page_url":"https://doi.org/10.1145/3027385.3029469","pdf_url":null,"source":null,"license":null,"license_id":null,"version":"publishedVersion","is_accepted":true,"is_published":true,"raw_source_name":"Proceedings of the Seventh International Learning Analytics & Knowledge Conference","raw_type":"proceedings-article"},"type":"article","indexed_in":["crossref"],"open_access":{"is_oa":true,"oa_status":"green","oa_url":"http://resolver.tudelft.nl/uuid:f100efd4-638b-4939-bec8-670af80020aa","any_repository_has_fulltext":true},"authorships":[{"author_position":"first","author":{"id":"https://openalex.org/A5074575547","display_name":"Guanliang Chen","orcid":"https://orcid.org/0000-0002-8236-3133"},"institutions":[{"id":"https://openalex.org/I98358874","display_name":"Delft University of Technology","ror":"https://ror.org/02e2c7k09","country_code":"NL","type":"education","lineage":["https://openalex.org/I98358874"]}],"countries":["NL"],"is_corresponding":true,"raw_author_name":"Guanliang Chen","raw_affiliation_strings":["Delft University of Technology, Delft, the Netherlands"],"affiliations":[{"raw_affiliation_string":"Delft University of Technology, Delft, the Netherlands","institution_ids":["https://openalex.org/I98358874"]}]},{"author_position":"middle","author":{"id":"https://openalex.org/A5102817700","display_name":"Dan Davis","orcid":"https://orcid.org/0000-0001-9529-1071"},"institutions":[{"id":"https://openalex.org/I98358874","display_name":"Delft University of Technology","ror":"https://ror.org/02e2c7k09","country_code":"NL","type":"education","lineage":["https://openalex.org/I98358874"]}],"countries":["NL"],"is_corresponding":false,"raw_author_name":"Dan Davis","raw_affiliation_strings":["Delft University of Technology, Delft, the Netherlands"],"affiliations":[{"raw_affiliation_string":"Delft University of Technology, Delft, the Netherlands","institution_ids":["https://openalex.org/I98358874"]}]},{"author_position":"middle","author":{"id":"https://openalex.org/A5110564894","display_name":"Markus Krause","orcid":null},"institutions":[{"id":"https://openalex.org/I1297971548","display_name":"International Computer Science Institute","ror":"https://ror.org/01ewh7m12","country_code":"US","type":"nonprofit","lineage":["https://openalex.org/I1297971548"]},{"id":"https://openalex.org/I95457486","display_name":"University of California, Berkeley","ror":"https://ror.org/01an7q238","country_code":"US","type":"education","lineage":["https://openalex.org/I95457486"]}],"countries":["US"],"is_corresponding":false,"raw_author_name":"Markus Krause","raw_affiliation_strings":["UC Berkeley ICSI"],"affiliations":[{"raw_affiliation_string":"UC Berkeley ICSI","institution_ids":["https://openalex.org/I1297971548","https://openalex.org/I95457486"]}]},{"author_position":"middle","author":{"id":"https://openalex.org/A5084915697","display_name":"Claudia Hauff","orcid":"https://orcid.org/0000-0001-9879-6470"},"institutions":[{"id":"https://openalex.org/I98358874","display_name":"Delft University of Technology","ror":"https://ror.org/02e2c7k09","country_code":"NL","type":"education","lineage":["https://openalex.org/I98358874"]}],"countries":["NL"],"is_corresponding":false,"raw_author_name":"Claudia Hauff","raw_affiliation_strings":["Delft University of Technology, Delft, the Netherlands"],"affiliations":[{"raw_affiliation_string":"Delft University of Technology, Delft, the Netherlands","institution_ids":["https://openalex.org/I98358874"]}]},{"author_position":"last","author":{"id":"https://openalex.org/A5108504427","display_name":"Geert\u2010Jan Houben","orcid":null},"institutions":[{"id":"https://openalex.org/I98358874","display_name":"Delft University of Technology","ror":"https://ror.org/02e2c7k09","country_code":"NL","type":"education","lineage":["https://openalex.org/I98358874"]}],"countries":["NL"],"is_corresponding":false,"raw_author_name":"Geert-Jan Houben","raw_affiliation_strings":["Delft University of Technology, Delft, the Netherlands"],"affiliations":[{"raw_affiliation_string":"Delft University of Technology, Delft, the Netherlands","institution_ids":["https://openalex.org/I98358874"]}]}],"institutions":[],"countries_distinct_count":2,"institutions_distinct_count":5,"corresponding_author_ids":["https://openalex.org/A5074575547"],"corresponding_institution_ids":["https://openalex.org/I98358874"],"apc_list":null,"apc_paid":null,"fwci":0.3881,"has_fulltext":false,"cited_by_count":3,"citation_normalized_percentile":{"value":0.69710468,"is_in_top_1_percent":false,"is_in_top_10_percent":false},"cited_by_percentile_year":{"min":89,"max":94},"biblio":{"volume":null,"issue":null,"first_page":"578","last_page":"579"},"is_retracted":false,"is_paratext":false,"is_xpac":false,"primary_topic":{"id":"https://openalex.org/T11122","display_name":"Online Learning and Analytics","score":0.9994999766349792,"subfield":{"id":"https://openalex.org/subfields/1706","display_name":"Computer Science Applications"},"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/T11122","display_name":"Online Learning and Analytics","score":0.9994999766349792,"subfield":{"id":"https://openalex.org/subfields/1706","display_name":"Computer Science Applications"},"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/T11704","display_name":"Mobile Crowdsensing and Crowdsourcing","score":0.9983000159263611,"subfield":{"id":"https://openalex.org/subfields/1706","display_name":"Computer Science Applications"},"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/T12761","display_name":"Data Stream Mining Techniques","score":0.9900000095367432,"subfield":{"id":"https://openalex.org/subfields/1702","display_name":"Artificial Intelligence"},"field":{"id":"https://openalex.org/fields/17","display_name":"Computer Science"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}}],"keywords":[{"id":"https://openalex.org/keywords/computer-science","display_name":"Computer science","score":0.7496403455734253},{"id":"https://openalex.org/keywords/task","display_name":"Task (project management)","score":0.7474798560142517},{"id":"https://openalex.org/keywords/massive-open-online-course","display_name":"Massive open online course","score":0.6847564578056335},{"id":"https://openalex.org/keywords/world-wide-web","display_name":"World Wide Web","score":0.5753135681152344},{"id":"https://openalex.org/keywords/recommender-system","display_name":"Recommender system","score":0.5242676734924316},{"id":"https://openalex.org/keywords/multimedia","display_name":"Multimedia","score":0.4893762469291687},{"id":"https://openalex.org/keywords/online-learning","display_name":"Online learning","score":0.4521583914756775},{"id":"https://openalex.org/keywords/online-course","display_name":"Online course","score":0.41682353615760803},{"id":"https://openalex.org/keywords/data-science","display_name":"Data science","score":0.355796754360199},{"id":"https://openalex.org/keywords/mathematics-education","display_name":"Mathematics education","score":0.19566160440444946},{"id":"https://openalex.org/keywords/engineering","display_name":"Engineering","score":0.11562785506248474},{"id":"https://openalex.org/keywords/psychology","display_name":"Psychology","score":0.06581014394760132}],"concepts":[{"id":"https://openalex.org/C41008148","wikidata":"https://www.wikidata.org/wiki/Q21198","display_name":"Computer science","level":0,"score":0.7496403455734253},{"id":"https://openalex.org/C2780451532","wikidata":"https://www.wikidata.org/wiki/Q759676","display_name":"Task (project management)","level":2,"score":0.7474798560142517},{"id":"https://openalex.org/C2777808570","wikidata":"https://www.wikidata.org/wiki/Q967853","display_name":"Massive open online course","level":2,"score":0.6847564578056335},{"id":"https://openalex.org/C136764020","wikidata":"https://www.wikidata.org/wiki/Q466","display_name":"World Wide Web","level":1,"score":0.5753135681152344},{"id":"https://openalex.org/C557471498","wikidata":"https://www.wikidata.org/wiki/Q554950","display_name":"Recommender system","level":2,"score":0.5242676734924316},{"id":"https://openalex.org/C49774154","wikidata":"https://www.wikidata.org/wiki/Q131765","display_name":"Multimedia","level":1,"score":0.4893762469291687},{"id":"https://openalex.org/C2986087404","wikidata":"https://www.wikidata.org/wiki/Q15946010","display_name":"Online learning","level":2,"score":0.4521583914756775},{"id":"https://openalex.org/C2986081426","wikidata":"https://www.wikidata.org/wiki/Q1068473","display_name":"Online course","level":2,"score":0.41682353615760803},{"id":"https://openalex.org/C2522767166","wikidata":"https://www.wikidata.org/wiki/Q2374463","display_name":"Data science","level":1,"score":0.355796754360199},{"id":"https://openalex.org/C145420912","wikidata":"https://www.wikidata.org/wiki/Q853077","display_name":"Mathematics education","level":1,"score":0.19566160440444946},{"id":"https://openalex.org/C127413603","wikidata":"https://www.wikidata.org/wiki/Q11023","display_name":"Engineering","level":0,"score":0.11562785506248474},{"id":"https://openalex.org/C15744967","wikidata":"https://www.wikidata.org/wiki/Q9418","display_name":"Psychology","level":0,"score":0.06581014394760132},{"id":"https://openalex.org/C201995342","wikidata":"https://www.wikidata.org/wiki/Q682496","display_name":"Systems engineering","level":1,"score":0.0}],"mesh":[],"locations_count":2,"locations":[{"id":"doi:10.1145/3027385.3029469","is_oa":false,"landing_page_url":"https://doi.org/10.1145/3027385.3029469","pdf_url":null,"source":null,"license":null,"license_id":null,"version":"publishedVersion","is_accepted":true,"is_published":true,"raw_source_name":"Proceedings of the Seventh International Learning Analytics & Knowledge Conference","raw_type":"proceedings-article"},{"id":"pmh:oai:tudelft.nl:uuid:f100efd4-638b-4939-bec8-670af80020aa","is_oa":true,"landing_page_url":"http://resolver.tudelft.nl/uuid:f100efd4-638b-4939-bec8-670af80020aa","pdf_url":null,"source":{"id":"https://openalex.org/S4306400906","display_name":"Research Repository (Delft University of Technology)","issn_l":null,"issn":null,"is_oa":false,"is_in_doaj":false,"is_core":false,"host_organization":"https://openalex.org/I98358874","host_organization_name":"Delft University of Technology","host_organization_lineage":["https://openalex.org/I98358874"],"host_organization_lineage_names":[],"type":"repository"},"license":"cc-by-nc-nd","license_id":"https://openalex.org/licenses/cc-by-nc-nd","version":"submittedVersion","is_accepted":false,"is_published":false,"raw_source_name":"","raw_type":"conference paper"}],"best_oa_location":{"id":"pmh:oai:tudelft.nl:uuid:f100efd4-638b-4939-bec8-670af80020aa","is_oa":true,"landing_page_url":"http://resolver.tudelft.nl/uuid:f100efd4-638b-4939-bec8-670af80020aa","pdf_url":null,"source":{"id":"https://openalex.org/S4306400906","display_name":"Research Repository (Delft University of Technology)","issn_l":null,"issn":null,"is_oa":false,"is_in_doaj":false,"is_core":false,"host_organization":"https://openalex.org/I98358874","host_organization_name":"Delft University of Technology","host_organization_lineage":["https://openalex.org/I98358874"],"host_organization_lineage_names":[],"type":"repository"},"license":"cc-by-nc-nd","license_id":"https://openalex.org/licenses/cc-by-nc-nd","version":"submittedVersion","is_accepted":false,"is_published":false,"raw_source_name":"","raw_type":"conference paper"},"sustainable_development_goals":[{"score":0.5099999904632568,"display_name":"Partnerships for the goals","id":"https://metadata.un.org/sdg/17"}],"awards":[],"funders":[],"has_content":{"pdf":false,"grobid_xml":false},"content_urls":null,"referenced_works_count":38,"referenced_works":["https://openalex.org/W1276866904","https://openalex.org/W1487531252","https://openalex.org/W1522808000","https://openalex.org/W1728530261","https://openalex.org/W1812976209","https://openalex.org/W1900422729","https://openalex.org/W1982464953","https://openalex.org/W1986715679","https://openalex.org/W1994211543","https://openalex.org/W1994740530","https://openalex.org/W1998933811","https://openalex.org/W2012265254","https://openalex.org/W2016757206","https://openalex.org/W2023718959","https://openalex.org/W2027859517","https://openalex.org/W2032365340","https://openalex.org/W2039958052","https://openalex.org/W2071097428","https://openalex.org/W2086145942","https://openalex.org/W2086235321","https://openalex.org/W2096050496","https://openalex.org/W2096459062","https://openalex.org/W2118069264","https://openalex.org/W2140918013","https://openalex.org/W2141846678","https://openalex.org/W2153378020","https://openalex.org/W2157300266","https://openalex.org/W2276569499","https://openalex.org/W2338421114","https://openalex.org/W2339218466","https://openalex.org/W2479485957","https://openalex.org/W2525379498","https://openalex.org/W2528720667","https://openalex.org/W2573629423","https://openalex.org/W2579358387","https://openalex.org/W2592323421","https://openalex.org/W2809648496","https://openalex.org/W4312098298"],"related_works":["https://openalex.org/W2588045479","https://openalex.org/W3171822798","https://openalex.org/W2387387592","https://openalex.org/W3111150353","https://openalex.org/W2357268223","https://openalex.org/W2286640297","https://openalex.org/W2807721994","https://openalex.org/W4390476759","https://openalex.org/W4210812943","https://openalex.org/W2165558212"],"abstract_inverted_index":{"Massive":[0],"Open":[1],"Online":[2],"Courses":[3],"(MOOCs)":[4],"aim":[5],"to":[6,20,52,59,72,83,100],"educate":[7],"the":[8,21,56,81],"world,":[9],"especially":[10],"learners":[11,71,101],"from":[12,61,104],"developing":[13],"countries.":[14],"While":[15],"MOOCs":[16],"are":[17,24],"certainly":[18],"available":[19],"masses,":[22],"they":[23,78],"not":[25],"yet":[26],"fully":[27],"accessible.":[28],"Although":[29],"all":[30],"course":[31,82],"content":[32],"is":[33,118],"just":[34],"clicks":[35],"away,":[36],"deeply":[37],"engaging":[38],"with":[39],"a":[40,43,50,62,67,89,113],"MOOC":[41,116],"requires":[42],"substantial":[44],"time":[45,57],"commitment,":[46],"which":[47,95],"frequently":[48],"becomes":[49],"barrier":[51],"success.":[53],"To":[54],"mitigate":[55],"required":[58],"learn":[60,79],"MOOC,":[63],"we":[64],"here":[65],"introduce":[66],"design":[68],"that":[69],"enables":[70],"earn":[73],"money":[74],"by":[75],"applying":[76],"what":[77],"in":[80],"real-world":[84],"marketplace":[85],"tasks.":[86],"We":[87],"present":[88],"Paid":[90],"Task":[91],"Recommender":[92],"System":[93],"(Rec-$ys),":[94],"automatically":[96],"recommends":[97],"course-relevant":[98],"tasks":[99],"as":[102],"drawn":[103],"online":[105],"freelance":[106],"platforms.":[107],"Rec-$ys":[108],"has":[109],"been":[110],"deployed":[111],"into":[112],"data":[114],"analysis":[115],"and":[117],"currently":[119],"under":[120],"evaluation.":[121]},"counts_by_year":[{"year":2022,"cited_by_count":1},{"year":2021,"cited_by_count":1},{"year":2020,"cited_by_count":1}],"updated_date":"2025-11-06T03:46:38.306776","created_date":"2017-03-16T00:00:00"}