Tagsplanations: Explaining Recommendations Using Tags

Total Page:16

File Type:pdf, Size:1020Kb

Tagsplanations: Explaining Recommendations Using Tags Tagsplanations: Explaining Recommendations Using Tags Jesse Vig Shilad Sen John Riedl Grouplens Research Grouplens Research Grouplens Research University of Minnesota University of Minnesota University of Minnesota [email protected] [email protected] [email protected] ABSTRACT While recommender systems tell users what items they might like, explanations of recommendations reveal why they might like them. Explanations provide many benefits, from im- proving user satisfaction to helping users make better deci- sions. This paper introduces tagsplanations, which are ex- planations based on community tags. Tagsplanations have two key components: tag relevance, the degree to which a tag describes an item, and tag preference, the user’s senti- ment toward a tag. We develop novel algorithms for esti- mating tag relevance and tag preference, and we conduct a Figure 1: Intermediary entities (center) relate user to recommended item. user study exploring the roles of tag relevance and tag prefer- ence in promoting effective tagsplanations. We also examine which types of tags are most useful for tagsplanations. Research shows that explanations help users make more ac- curate decisions [1], improve user acceptance of recommen- ACM Classification Keywords dations [6], and increase trust in the recommender system H.5.3 Information Interfaces and Presentation: Group and [13]. Moreover, studies indicate that users want explana- Organization Interfaces—Collaborative computing; H.5.2 In- tions of their recommendations – a survey of users of one formation Interfaces and Presentation: User Interfaces movie recommender site showed that 86% of those surveyed wanted an explanation feature added to the site [6]. General Terms While many different types of explanation facilities exist, Design, Experimentation, Human Factors they all seek to show how a recommended item relates to a user’s preferences. As Figure 1 illustrates, a common tech- Author Keywords nique for establishing the relationship between user and rec- Explanations, tagging, recommender systems ommended item is to use an intermediary entity. An inter- mediary entity is needed because the direct relationship be- INTRODUCTION tween user and item is unknown, assuming that the user has While much of the research in recommender systems has not yet tried the item. In the Netflix example above, the inter- focused on improving the accuracy of recommendations, re- mediary entity is the list of previously rated movies shown in cent work suggests a broader set of goals including trust, the explanation. The relationship between the user and these user satisfaction, and transparency [16, 1, 13, 6]. A key to movies is that he or she has rated them positively. The rela- achieving this broader set of goals is to explain recommen- tionship between these movies and the recommended movie dations to users. While recommendations tell users what is that other users who liked these movies also liked the rec- items they might like, explanations reveal why they might ommended movie. like them. An example is the “Why this was recommended” feature on Netflix1. Netflix explains movie recommenda- Explanations of recommendations fall into one of three cat- tions by showing users similar movies they have rated highly egories: item-based, user-based, and feature-based, depend- in the past. ing on the type of intermediary entity used to relate the user 1 to the recommended item. In item-based explanations like http://www.netflix.com the Netflix example, a set of items serves as the intermedi- ary entity. User-based explanations utilize other users as in- termediary entities. For example, Herlocker et al. designed Permission to make digital or hard copies of all or part of this work for a explanation that shows a user how other users with simi- personal or classroom use is granted without fee provided that copies are lar taste rated the recommended item [6]. Feature-based ap- not made or distributed for profit or commercial advantage and that copies proaches use features or characteristics of the recommended bear this notice and the full citation on the first page. To copy otherwise, or item as intermediary entities. For example, one movie rec- republish, to post on servers or to redistribute to lists, requires prior specific permission and/or a fee. ommender prototype uses movie features including genre, IUI’09, February 8 - 11, 2009, Sanibel Island, Florida, USA. director, and cast to justify recommendations [14]. Copyright 2009 ACM 978-1-60558-331-0/09/02...$5.00. We present a new type of explanation that uses tags as fea- recommended. Tagsplanations promote understanding by tures, which we call a tagsplanation. The intermediary en- demonstrating how a tag relates to the item and how the tity for tagsplanations is a tag or a set of tags. For example: user relates to the tag. We investigate the role of these two components in helping users understand the recommenda- “We recommend the movie Fargo because it is tagged with tion overall. quirky and you have enjoyed other movies tagged with quirky.” RQ-Effectiveness: What is the role of tag preference and tag relevance in helping users determine if they will like Tags have become increasingly popular on websites such as the item? Delicious2, Flickr3, and Amazon4, and they have many qual- ities that make them useful for explanations. As described in We investigate whether users prefer information about the [5], tags may describe what an item is, what it is about, or relationship between themselves and the tag (tag preference) what its characteristics are – all of which may be useful for explaining a recommendation. Another advantage is that no or between the tag and the item (tag relevance) to make good experts are needed to create and maintain tags, since tags decisions. are applied by the users themselves. Furthermore, tags pro- vide both factual and subjective descriptions [11]. However, RQ-Mood: What is the role of tag preference and tag rel- tags present unique challenges, including issues of tag qual- evance in helping users decide if an item fits their current ity [10] and tag redundancy [5]. mood? We study two aspects of tag-based explanations: the rela- Recommender systems typically do not consider the user’s tionship of the tag to the recommended item, which we call mood when generating recommendations. Explanations pro- tag relevance, and the relationship of the user to the tag, vide users with additional information that can help them which we call tag preference. Tag relevance represents the decide if an item fits their current mood. We investigate the degree to which a tag describes a given item. For example, relative importance of tag preference and tag relevance for consider a tagsplanation for the movie Pulp Fiction that uses revealing mood compatibility. the tag “dark comedy”. In this example, tag relevance would measure how well “dark comedy” describes Pulp Fiction. RQ-Tag-Type: What types of tags are most useful in tags- Tag preference, on the other hand, measures the user’s sen- planations? timent to the given tag, for example how much the user likes or dislikes dark comedies. Tag relevance and tag preference A wide variety of tags may be applied to an item, some of are orthogonal to one another: the former is item-specific which may be more suitable for explanations than others. and the latter is user-specific. As discussed in [10], factual tags identify facts about an item subjective Our design of tagsplanations is motivated by three goals: such as people, places, or concepts, while tags ex- justification, effectiveness, and mood compatibility. Justi- press users’ opinions of an item. We investigate the relative fication is the ability of the system to help the user under- usefulness of factual tags versus subjective tags, and analyze stand why an item was recommended [6]. Justification dif- which specific tags perform best. fers from transparency [16] because justifications may not To answer these research questions, we designed a tagspla- reveal the actual mechanisms of the recommender algorithm. nation feature for the MovieLens movie recommender site5 Tintarev et al. define effectiveness as the ability of the expla- and conducted an online user study. Participants in the study nation to help users make good decisions. Mood compati- viewed 4 types of tagsplanations, each of which handles tag bility is the ability of the explanation to convey whether or preference and tag relevance in a different way. Participants not an item matches a user’s mood. A recent study showed evaluated each tagsplanation based on how well it achieved that users are interested in explanations with mood-related the goals of justification, effectiveness, and mood compati- features [15]. bility. We then analyze the results to determine the roles of In this paper, we investigate the roles of tag relevance and tag relevance and tag preference in promoting these 3 goals. tag preference in tagsplanations. Specifically, we consider Subjects also evaluate specific tags, and we compare the re- the following research questions: sults for subjective tags versus factual tags. RQ-Justification: What is the role of tag preference and RELATED WORK tag relevance in helping users understand their recom- Item-based explanations. Item-based approaches use items mendation? as intermediary entities to relate the user to the recommended item. An example is the “Why this was recommended” fea- Explanations help users understand why a given item was ture on Netflix, which shows users their past ratings for a set of related movies. Similarly, Amazon shows users their past purchases that motivated a recommendation of a new item. 2http://del.icio.us Studies show that item-based explanations improve users’ 3http://www.flickr.com 4http://www.amazon.com 5http://www.movielens.org acceptance of recommendations [6] and help users make ac- many of which may be addressed by using tags. One lim- curate decisions [1].
Recommended publications
  • A Grouplens Perspective
    From: AAAI Technical Report WS-98-08. Compilation copyright © 1998, AAAI (www.aaai.org). All rights reserved. RecommenderSystems: A GroupLensPerspective Joseph A. Konstan*t , John Riedl *t, AI Borchers,* and Jonathan L. Herlocker* *GroupLensResearch Project *Net Perceptions,Inc. Dept. of ComputerScience and Engineering 11200 West78th Street University of Minnesota Suite 300 Minneapolis, MN55455 Minneapolis, MN55344 http://www.cs.umn.edu/Research/GroupLens/ http://www.netperceptions.com/ ABSTRACT identifying sets of articles by keyworddoes not scale to a In this paper, wereview the history and research findings of situation in which there are thousands of articles that the GroupLensResearch project I and present the four broad contain any imaginable set of keywords. Taken together, research directions that we feel are most critical for these two weaknesses represented an opportunity for a new recommender systems. type of filtering, that would focus on finding which INTRODUCTION:A History of the GroupLensProject available articles matchhuman notions of quality and taste. The GroupLens Research project began at the Computer Such a system would be able to produce a list of articles Supported Cooperative Work (CSCW)Conference in 1992. that each user wouldlike, independentof their content. Oneof the keynote speakers at the conference lectured on a Wedecided to apply our ideas in the domain of Usenet his vision of an emerging information economy,in which news. Usenet screamsfor better information filtering, with most of the effort in the economywould revolve around hundreds of thousands of articles posted daily. Manyof the production, distribution, and consumptionof information, articles in each Usenet newsgroupare on the sametopic, so rather than physical goods and services.
    [Show full text]
  • A Recommender System for Groups of Users
    PolyLens: A Recommender System for Groups of Users Mark O’Connor, Dan Cosley, Joseph A. Konstan, and John Riedl Department of Computer Science and Engineering, University of Minnesota, Minneapolis, MN 55455 USA {oconnor;cosley;konstan;riedl}@cs.umn.edu Abstract. We present PolyLens, a new collaborative filtering recommender system designed to recommend items for groups of users, rather than for individuals. A group recommender is more appropriate and useful for domains in which several people participate in a single activity, as is often the case with movies and restaurants. We present an analysis of the primary design issues for group recommenders, including questions about the nature of groups, the rights of group members, social value functions for groups, and interfaces for displaying group recommendations. We then report on our PolyLens prototype and the lessons we learned from usage logs and surveys from a nine-month trial that included 819 users. We found that users not only valued group recommendations, but were willing to yield some privacy to get the benefits of group recommendations. Users valued an extension to the group recommender system that enabled them to invite non-members to participate, via email. Introduction Recommender systems (Resnick & Varian, 1997) help users faced with an overwhelming selection of items by identifying particular items that are likely to match each user’s tastes or preferences (Schafer et al., 1999). The most sophisticated systems learn each user’s tastes and provide personalized recommendations. Though several machine learning and personalization technologies can attempt to learn user preferences, automated collaborative filtering (Resnick et al., 1994; Shardanand & Maes, 1995) has become the preferred real-time technology for personal recommendations, in part because it leverages the experiences of an entire community of users to provide high quality recommendations without detailed models of either content or user tastes.
    [Show full text]
  • Community, Impact and Credit: Where Should I Submit My Papers?
    Panels February 23–27, 2013, San Antonio, Texas, USA Community, Impact and Credit: Where should I submit my papers? Abstract Aaron Halfaker R. Stuart Geiger We (the authors of CSCWs program) have finite time and GroupLens Research School of Information energy that can be invested into our publications and the University of Minnesota University of CA, Berkeley research communities we value. While we want our work [email protected] [email protected] to have the most impact possible, we also want to grow Cliff Lampe Loren Terveen and support productive research communities within School of Information GroupLens Research which to have this impact. This panel discussion explores Michigan State University University of Minnesota the costs and benefits of submitting papers to various [email protected] [email protected] tiers of conferences and journals surrounding CSCW and Amy Bruckman Brian Keegan reflects on the value of investing hours into building up a College of Computing Northeastern University research community. Georgia Inst. of Technology [email protected] [email protected] Author Keywords Aniket Kittur Geraldine Fitzpatrick community; credit; impact; publishing; peer review HCI Institute Vienna University of Carnegie Mellon University Technology ACM Classification Keywords [email protected] geraldine.fi[email protected] H.5.0. [Information Interfaces and Presentation (e.g. HCI)]: General Introduction We (the authors of CSCWs program) have finite time and energy that can be invested into our publications and the research communities we value. In order to allow our work to have an impact, we must also grow and maintain Copyright is held by the author/owner(s).
    [Show full text]
  • Improvements in Holistic Recommender System Research
    Improvements in Holistic Recommender System Research A DISSERTATION SUBMITTED TO THE FACULTY OF THE UNIVERSITY OF MINNESOTA BY Daniel Allen Kluver IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY Joseph A. Konstan August, 2018 c Daniel Allen Kluver 2018 ALL RIGHTS RESERVED Dedication This dissertation is dedicated to my family, my friends, my advisers John Riedl and Joseph Konstan, my colleagues, both at GroupLens research and at Macalester College, and everyone else who believed in me and supported me along the way. Your support meant everything when I couldn’t support myself. Your belief meant everything when I couldn’t believe in myself. I couldn’t have done this without your help. i Abstract Since the mid 1990s, recommender systems have grown to be a major area of de- ployment in industry, and research in academia. A through-line in this research has been the pursuit, above all else, of the perfect algorithm. With this admirable focus has come a neglect of the full scope of building, maintaining, and improving recom- mender systems. In this work I outline a system deployment and a series of offline and online experiments dedicated to improving our holistic understanding of recommender systems. This work explores the design, algorithms, early performance, and interfaces of recommender systems within the scope of how they are interconnected with other aspects of the system. This work explores many indivisual aspects of a recommender system while keeping in mind how they are connected to other aspects of
    [Show full text]
  • Truth and Lies of What People Are Really Thinking
    Dedication For Lex and Stella Epigraph Everything we see is a perspective, not the truth —Falsely attributed to Marcus Aurelius (author unknown) Contents Cover Title Page Dedication Epigraph Introduction Part One Genuine Deceptions 1 Body Language Lies 2 Powerful Thinking 3 Mind Your Judgments 4 Scan for Truth Part Two Dating 5 They’re Totally Checking Me Out! 6 Playing Hard-to-Get 7 Just Feeling Sorry for Me 8 I’m Being Ghosted 9 What a Complete Psycho! 10 They Are Running the Show 11 I’m Going to Pay for That! 12 They Are So Mad at Me 13 A Lying Cheat? 14 Definitely into My Friend 15 A Match Made in Heaven? 16 They Are So Breaking Up! Part Three Friends and Family 17 Thick as Thieves 18 My New Bff? 19 Fomo 20 Control Freak 21 Too Close for Comfort 22 They’ll Never Fit in with My Family 23 House on Fire! 24 I Am Boring the Pants off Them 25 Lying Through Their Teeth 26 Persona Non Grata 27 Invisible Me Part Four Working Life 28 I Aced That Interview—So, Where’s the Job Offer? 29 They Hate My Work 30 Big Dog 31 Never Going to See Eye to Eye 32 Cold Fish 33 They’re Gonna Blow! 34 This Meeting Is a Waste of Time 35 Looks Like a Winning Team 36 So, You Think You’re the Boss 37 Hand in the Cookie Jar Summary Bonus Bluff Learn more Acknowledgments Notes About the Authors Praise for Truth & Lies Also by Mark Bowden Copyright About the Publisher Introduction WE CAN ALL RECALL EXAMPLES when our sense of what another person was thinking turned out to be the truth.
    [Show full text]
  • User Session Identification Based on Strong Regularities in Inter-Activity
    User Session Identification Based on Strong Regularities in Inter-activity Time Aaron Halfaker Os Keyes Daniel Kluver Wikimedia Foundation Wikimedia Foundation GroupLens Research [email protected] [email protected] University of Minnesota [email protected] Jacob Thebault-Spieker Tien Nguyen Kenneth Shores GroupLens Research GroupLens Research GroupLens Research University of Minnesota University of Minnesota University of Minnesota [email protected] [email protected] [email protected] Anuradha Uduwage Morten Warncke-Wang GroupLens Research GroupLens Research University of Minnesota University of Minnesota [email protected] [email protected] ABSTRACT 1. INTRODUCTION Session identification is a common strategy used to develop In 2012, we had an idea for a measurement strategy that metrics for web analytics and behavioral analyses of user- would bring insight and understanding to the nature of par- facing systems. Past work has argued that session identifica- ticipation in an online community. While studying partic- tion strategies based on an inactivity threshold is inherently ipation in Wikipedia, the open, collaborative encyclopedia, arbitrary or advocated that thresholds be set at about 30 we found ourselves increasingly curious about the amount of minutes. In this work, we demonstrate a strong regularity time that volunteer contributors invested into the encyclope- in the temporal rhythms of user initiated events across sev- dia's construction. Past work measuring editor engagement eral different domains of online activity (incl. video gaming, relied on counting the number of contributions made by a search, page views and volunteer contributions). We de- user1, but we felt that the amount of time editors spent scribe a methodology for identifying clusters of user activity editing might serve as a more appropriate measure.
    [Show full text]
  • A Roll of the Dice
    Confidence Displays and Training in Recommender Systems Sean M. McNee, Shyong K. Lam, Catherine Guetzlaff, Joseph A. Konstan, and John Riedl GroupLens Research Project Department of Computer Science and Engineering University of Minnesota, MN 55455 USA {mcnee, lam, guetzlaf, konstan, riedl}@cs.umn.edu Abstract: Recommender systems help users sort through vast quantities of information. Sometimes, however, users do not know if they can trust the recommendations they receive. Adding a confidence metric has the potential to improve user satisfaction and alter user behavior in a recommender system. We performed an experiment to measure the effects of a confidence display as a component of an existing collaborative filtering- based recommender system. Minimal training improved use of the confidence display compared to no training. Novice users were less likely to notice, understand, and use the confidence display than experienced users of the system. Providing training about a confidence display to experienced users greatly reduced user satisfaction in the recommender system. These results raise interesting issues and demonstrate subtle effects about how and when to train users when adding features to a system. Keywords: Recommender Systems, Collaborative Filtering, Confidence Displays, Risk, Training range. For example, a fan of science fiction may 1 Introduction receive a recommendation for a particular art film because other science fiction fans liked it. This People face the problem of information overload serendipity in recommendations is one of the every day. As the number of web sites, books, strengths of collaborative filtering. magazines, research papers, and so on continue to It is also one of its weaknesses. CF algorithms rise, it is getting harder to keep up.
    [Show full text]
  • Evaluating Collaborative Filtering Recommender Systems
    Evaluating Collaborative Filtering Recommender Systems JONATHAN L. HERLOCKER Oregon State University and JOSEPH A. KONSTAN, LOREN G. TERVEEN, and JOHN T. RIEDL University of Minnesota Recommender systems have been evaluated in many, often incomparable, ways. In this article, we review the key decisions in evaluating collaborative filtering recommender systems: the user tasks being evaluated, the types of analysis and datasets being used, the ways in which prediction quality is measured, the evaluation of prediction attributes other than quality, and the user-based evaluation of the system as a whole. In addition to reviewing the evaluation strategies used by prior researchers, we present empirical results from the analysis of various accuracy metrics on one con- tent domain where all the tested metrics collapsed roughly into three equivalence classes. Metrics within each equivalency class were strongly correlated, while metrics from different equivalency classes were uncorrelated. Categories and Subject Descriptors: H.3.4 [Information Storage and Retrieval]: Systems and Software—performance Evaluation (efficiency and effectiveness) General Terms: Experimentation, Measurement, Performance Additional Key Words and Phrases: Collaborative filtering, recommender systems, metrics, evaluation 1. INTRODUCTION Recommender systems use the opinions of a community of users to help indi- viduals in that community more effectively identify content of interest from a potentially overwhelming set of choices [Resnick and Varian 1997]. One of This research was supported by the National Science Foundation (NSF) under grants DGE 95- 54517, IIS 96-13960, IIS 97-34442, IIS 99-78717, IIS 01-02229, and IIS 01-33994, and by Net Perceptions, Inc. Authors’ addresses: J. L. Herlocker, School of Electrical Engineering and Computer Science, Oregon State University, 102 Dearborn Hall, Corvallis, OR 97331; email: [email protected]; J.
    [Show full text]
  • The Production and Consumption of Quality Content in Peer Production Communities
    The Production and Consumption of Quality Content in Peer Production Communities A Dissertation SUBMITTED TO THE FACULTY OF THE UNIVERSITY OF MINNESOTA BY Morten Warncke-Wang IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY Loren Terveen and Brent Hecht December, 2016 Copyright c 2016 M. Warncke-Wang All rights reserved. Portions copyright c Association for Computing Machinery (ACM) and is used in accordance with the ACM Author Agreement. Portions copyright c Association for the Advancement of Artificial Intelligence (AAAI) and is used in accordance with the AAAI Distribution License. Map tiles used in illustrations are from Stamen Design and published under a CC BY 3.0 license, and from OpenStreetMap and published under the ODbL. Dedicated in memory of John. T. Riedl, Ph.D professor, advisor, mentor, squash player, friend i Acknowledgements This work would not be possible without the help and support of a great number of people. I would first like to thank my family, in particular my parents Kari and Hans who have had to see yet another of their offspring fly off to the United States for a prolonged period of time. They have supported me in pursuing my dreams even when it meant I would be away from them. I also thank my brother Hans and his fiancée Anna for helping me get settled in Minnesota, solving everyday problems, and for the good company whenever I stopped by. Likewise, I thank my brother Carl and his wife Bente whom I have only been able to see ever so often, but it has always been moments I have cherished.
    [Show full text]
  • Item-Based Collaborative Filtering Recommendation Algorithms
    Item-Based Collaborative Filtering Recommendation Algorithms Badrul Sarwar, George Karypis, Joseph Konstan, and John Riedl f×aÖÛaÖ¸ kaÖÝÔi׸ kÓÒרaÒ¸ ÖiedÐg@c׺ÙÑÒºedÙ GroupLens Research Group/Army HPC Research Center Department of Computer Science and Engineering University of Minnesota, Minneapolis, MN 55455 ÚaiÐabÐe iÒfÓÖÑaØiÓÒ ØÓ ¬Òd ØhaØ Ûhichi× ABSTRACT ØhÖÓÙgh aÐÐ Øhe a ÑÓר ÚaÐÙabÐe ØÓ Ù׺ ÊecÓÑÑeÒdeÖ ×ÝרeÑ× aÔÔÐÝ kÒÓÛÐedge di×cÓÚeÖÝ ØechÒiÕÙe× ÇÒe Óf Øhe ÑÓר ÔÖÓÑi×iÒg ×ÙchØechÒÓÐÓgie× i× cÓÐ ÐabÓÖa¹ ØÓ Øhe ÔÖÓbÐeÑ Óf ÑakiÒg Ô eÖ×ÓÒaÐiÞed ÖecÓÑÑeÒdaØiÓÒ× fÓÖ ØiÚe ¬ÐØeÖiÒg [½9¸ ¾7¸ ½4¸ ½6]º CÓÐÐab ÓÖaØiÚe ¬ÐØeÖiÒg ÛÓÖk× bÝ iÒfÓÖÑaØiÓÒ¸ ÔÖÓ dÙcØ× ÓÖ ×eÖÚice× dÙÖiÒg a ÐiÚeiÒØeÖacØiÓÒº bÙiÐdiÒg a daØaba×e Óf ÔÖefeÖeÒce× fÓÖ iØeÑ× bÝ Ù×eÖ׺ AÒeÛ Ìhe×e ×ÝרeÑ׸ e×Ô eciaÐÐÝ Øhe k¹ÒeaÖeר ÒeighbÓÖ cÓÐÐabÓÖa¹ Ù×eÖ¸ ÆeÓ¸ i× ÑaØched agaiÒר Øhe daØaba×e ØÓ di×cÓÚeÖ Òeigh¹ ØiÚe ¬ÐØeÖiÒg ba×ed ÓÒe׸ aÖe achieÚiÒg Ûide×ÔÖead ×Ùcce×× ÓÒ bÓÖ׸ Ûhich aÖe ÓØheÖ Ù×eÖ× ÛhÓ haÚe hiרÓÖicaÐÐÝ had ×iÑiÐaÖ Øhe Ïebº Ìhe ØÖeÑeÒdÓÙ× gÖÓÛØh iÒ Øhe aÑÓÙÒØÓfaÚaiй Øaרe ØÓ ÆeÓº ÁØeÑ× ØhaØ Øhe Òeighb ÓÖ× Ðike aÖe ØheÒ ÖecÓѹ abÐe iÒfÓÖÑaØiÓÒ aÒd Øhe ÒÙÑb eÖ Óf Úi×iØÓÖ× ØÓ Ïeb ×iØe× iÒ ÑeÒded ØÓ ÆeÓ¸ a× he ÛiÐÐ ÔÖÓbabÐÝ aÐ×Ó Ðike ØheѺ CÓÐÐab¹ ÖeceÒØÝeaÖ× Ô Ó×e× ×ÓÑe keÝ chaÐÐeÒge× fÓÖ ÖecÓÑÑeÒdeÖ ×Ý×¹ ÓÖaØiÚe ¬ÐØeÖiÒg ha× beeÒ ÚeÖÝ ×Ùcce××fÙÐ iÒ b ÓØh Öe×eaÖch ØeÑ׺ Ìhe×e aÖe: ÔÖÓ dÙciÒg high ÕÙaÐiØÝ ÖecÓÑÑeÒdaØiÓÒ׸ aÒd ÔÖacØice¸ aÒd iÒ b ÓØh iÒfÓÖÑaØiÓÒ ¬ÐØeÖiÒg aÔÔÐicaØiÓÒ× Ô eÖfÓÖÑiÒg ÑaÒÝ ÖecÓÑÑeÒdaØiÓÒ× Ô eÖ ×ecÓÒd fÓÖ ÑiÐÐiÓÒ× aÒd E¹cÓÑÑeÖce aÔÔÐicaØiÓÒ׺
    [Show full text]
  • Movielens Unplugged: Experiences with an Occasionally Connected Recommender System
    MovieLens Unplugged: Experiences with an Occasionally Connected Recommender System Bradley N. Miller, Istvan Albert, Shyong K. Lam, Joseph A. Konstan, John Riedl GroupLens Research Group University of Minnesota Minneapolis, MN 55455 {bmiller,ialbert,lam,konstan,riedl}@cs.umn.edu http://www.grouplens.org ABSTRACT do not help you when you are browsing the aisles of your Recommender systems have changed the way people shop favorite bricks and mortar store. online. Recommender systems on wireless mobile devices Imagine that you have just come to the end of the new re- may have the same impact on the way people shop in stores. lease aisle at your local video store. Nothing along the way We present our experience with implementing a recommender caught your attention and the rows and rows of older videos system on a PDA that is occasionally connected to the net- look too daunting to even start wandering through. What work. This interface helps users of the MovieLens movie rec- do you do? Do you leave the store empty handed? No, ommendation service select movies to rent, buy, or see while instead you pull out your PDA and start up its browser. away from their computer. The results of a nine month field Through the PDA’s browser you access the MovieLens Un- study show that although there are several challenges to plugged (MLU) service that recommends videos you might overcome, mobile recommender systems have the potential be interested in. One of the highest recommended videos is to provide value to their users today. just what you had in mind so you find it and rent it for the night.
    [Show full text]
  • Narayan Umn 0130M 20436.Pdf
    What is the Value of Rating Obscure Items? An Analysis of the Effect of Less-Popular Item Ratings on Recommendation Quality A Dissertation SUBMITTED TO THE FACULTY OF THE UNIVERSITY OF MINNESOTA BY Anshuman Narayan IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTERS OF SCIENCE Joseph A. Konstan June, 2019 Copyright © 2019 A. Narayan. All rights reserved. Dedicated in honor of Shashi Narayan and Krishnan Adhi Narayan i Acknowledgements Many people have helped me along this two-year journey to complete my Master’s degree and I would be remiss in not thanking them. I would like to thank Professor Joseph Konstan for guiding me through this journey and teaching me so much about not only recommender systems but also how to conduct good research work and in- culcating in me the perseverance to conduct and complete this work. I owe a lot of what I have learned these two years to him. I would like to thank the Professors at the University of Minnesota that I’ve been fortunate enough to study under for all the knowledge I’ve gained from them. I have gained immense respect and inspiration from witnessing the passion they hold for teaching. I leave the this University knowing so much more, and knowing that there is so much more to know, and I am indebted to them for this. I would like to thank members of the GroupLens research lab for their patience and kindness in helping me,providing me great advice and always being open to discussing whatever I was stuck with.
    [Show full text]