Introduction toRecommender SystemsDr.sc.AmancioBouzaJan.27th,2017

WhoamI

Dr.sc.AmancioBouzaRecommenderSystemExpert,Intrapreneur

Let’sconnect:https://ch.linkedin.com/in/amanciobouza

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1Mio$Whatare

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1Mio$PrizeforbeatingNetflix’sRecommenderSystemby10%

https://en.wikipedia.org/wiki/Netflix_Prize

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Why?

Worldhaschanged:OnlineRetailervsB&MRetailer

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Amazon:2.3Mio* B&M:40k-100k*

[Brynjolfsson etal.,2003];*numberofbooks

forUSbookmarketinYear2000only…imaginetoday!

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$1.03BinSocialWelfare[Brynjolfsson &.Smith,2000]

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Whatdoesitmean?

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[Brynjolfsson &.Smith,2000]

UnlimitedOnlineProductCataloguesandFilteringAlgorithmshave

7-10xHigherImpactonSocialWelfarethanPriceCompetitioninCompetitiveMarkets

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SearchEngine:

ConsumersearchesrightProductRecommenderSystem:

ProductfindsrightConsumer

ParadigmShift

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WhatarePreferences?

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PreferencescanbedescribedwiththeUtilityFunction(Microeconomics)

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ContentFiltering

UseMachineLearningtoLearnanIndividual’sPreferences

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[Bouzaetal.,2009],[Bouza,2012]

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->Good->Bad

RepresentPreferences,e.g.,asDecisionTree

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[Bouza,2012]

Let’sbepragmatic:MachineLearningModelapproximatesUtilityFunction

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[Bouza,2012]

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“Let’srateaniPodNano(green)onAmazonandcheckourrecommendations”,2008

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Well…Doyou call this ausefull recommendation?Basedonapersonaltruestoryin2008

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CollaborativeFiltering

BasisforCollaborativeFiltering:User-ItemMatrix

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CollaborativeFiltering:Peoplewhosharedsimilarpreferencesinthepast,willsharesimilarpreferencesinthefuture

CollaborativeFiltering

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Peoplewhosharesimilarprefernces inthepastcontinuetodosointhefuture.

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My favourites:“BLACKOUT” and “ZERO”

from M. Elsberg

Peoplewhohavesimilarpreferencesinthepast,continuetodosointhefuture.

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My favourites:“BLACKOUT” and “ZERO”

from M. Elsberg

What about“HELIX”?

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But…

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WhataboutbothIndividuals’PreferencesbesideItemsbothrated?

OnlyItemsbothratedprovidesinformation

??

???

?

? ?

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Hypothesis-BasedCollaborativeFiltering[Bouza,2008-2012]

SimilarityofHypothesizedPreferencesakaMachineLearningModels

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[Bouza,2009]

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DailyChallengesinDataPreparation

What’sthemovietitleinChina?

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TranslatedMovieTitle:

He’saGhost

http://thoughtcatalog.com/nico-lang/2013/09/51-hilariously-bad-translations-of-movie-titles-that-are-better-than-the-original/

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Don‘t worry,no spoiler ;)

HypothesizedPartialPreferences(HPP)

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HypothesizedPartialPreferencesSimilarityMatrix

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[Bouza,2012]

SimilarityoftwoMachineLearningModels

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[Bouza,2012]

Hypothesis-BasedCollaborativeFilteringoutperformsothers

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[Bouza,2012]

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OtherApplicationsof

MachineLearningModelSimilarity

ApplyingHypothesis-BasedCollaborativeFilteringtoCross-ProjectDefectPrediction

41[Zenger&Bouza,2011] http://www.merlin.uzh.ch/publication/show/4535

BuildingaTexasHold’em PokerBotbasedonaHypothesis-BasedCollaborativeFilteringApproach

42[Kaul &Bouza,2011] http://www.merlin.uzh.ch/publication/show/2488

GroupRecommendationsinGoogleWaveConversionviaChatBotandRecommenderAPI

43[Bouza,2009] http://blog.cpoet.net/providing-movie-recommendations-to-groups-in-google-wave/

Yourturn!Whereareyougoingtoapplythismagicformula?

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Getit

FreeDownload:https://www.linkedin.com/pulse/how-ais-collaborate-retrieve-recommendations-everybody-amancio-bouza?trk=pulse_spock-articles

BuyBookonAmazon:110$https://www.amazon.com/dp/1105585085

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MoreRecommendationApplications:http://blog.cpoet.net/

Findmoreapplicationandideasthatmasterandbachelorstudentsimplementedhere:http://blog.cpoet.net/what-makes-a-location-really-interesting-and-how-to-exploit-it-to-improve-location-recommendations/http://blog.cpoet.net/applying-collaborative-filtering-to-cross-project-defect-prediction/http://blog.cpoet.net/building-an-agent-for-texas-holdem-poker-based-on-a-recommender-system/http://blog.cpoet.net/how-ratings-and-trust-inferrencing-establish-healthyow-ratings-and-trust-inferencing-establish-h-online-markets/http://blog.cpoet.net/considering-seasonal-effects-in-location-recommendations-with-recommendation-clouds-metaphor/http://blog.cpoet.net/proposal-using-collaborative-filtering-to-create-a-win-win-win-situation-and-engage-people-with-ubs-has-been-awarded/http://blog.cpoet.net/applicability-of-social-network-graph-patterns-to-recommender-systems/http://blog.cpoet.net/providing-movie-recommendations-to-groups-in-google-wave/http://blog.cpoet.net/personal-private-movie-recommender-system-at-the-semantic-web-challenge/http://blog.cpoet.net/202/http://blog.cpoet.net/personal-cross-site-movie-recommender-system-implemented-as-mozilla-firefox-add-on/http://blog.cpoet.net/probabilistic-partial-user-model-similarity-for-collaborative-filtering/http://blog.cpoet.net/semtree-ontology-based-decision-tree-algorithm-for-recommender-systems-at-the-iswc-2008/

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Let’sconnectandexchangeideas

Dr.sc.AmancioBouzaRecommenderSystemExpert,Intrapreneur

Let’sconnect:https://ch.linkedin.com/in/amanciobouza

Followme:https://twitter.com/AmancioBouza