Programming Collective Intelligence

Total Page:16

File Type:pdf, Size:1020Kb

Programming Collective Intelligence Praise for Programming Collective Intelligence “I review a few books each year, and naturally, I read a fair number during the course of my work. And I have to admit that I have never had quite as much fun reading a preprint of a book as I have in reading this. Bravo! I cannot think of a better way for a developer to first learn these algorithms and methods, nor can I think of a better way for me (an old AI dog) to reinvigorate my knowledge of the details.” — Dan Russell, Uber Tech Lead, Google “Toby’s book does a great job of breaking down the complex subject matter of machine- learning algorithms into practical, easy-to-understand examples that can be used directly to analyze social interaction across the Web today. If I had this book two years ago, it would have saved me precious time going down some fruitless paths.” — Tim Wolters, CTO, Collective Intellect “Programming Collective Intelligence is a stellar achievement in providing a comprehensive collection of computational methods for relating vast amounts of data. Specifically, it applies these techniques in context of the Internet, finding value in otherwise isolated data islands. If you develop for the Internet, this book is a must-have.” — Paul Tyma, Senior Software Engineer, Google Programming Collective Intelligence Other resources from O’Reilly Related titles Web 2.0 Report AI for Game Developers Learning Python Mastering Algorithms with Mastering Algorithms with C Perl oreilly.com oreilly.com is more than a complete catalog of O’Reilly books. You’ll also find links to news, events, articles, weblogs, sample chapters, and code examples. oreillynet.com is the essential portal for developers interested in open and emerging technologies, including new platforms, pro- gramming languages, and operating systems. Conferences O’Reilly brings diverse innovators together to nurture the ideas that spark revolutionary industries. We specialize in document- ing the latest tools and systems, translating the innovator’s knowledge into useful skills for those in the trenches. Visit conferences.oreilly.com for our upcoming events. Safari Bookshelf (safari.oreilly.com) is the premier online refer- ence library for programmers and IT professionals. Conduct searches across more than 1,000 books. Subscribers can zero in on answers to time-critical questions in a matter of seconds. Read the books on your Bookshelf from cover to cover or sim- ply flip to the page you need. Try it today for free. Programming Collective Intelligence Building Smart Web 2.0 Applications Toby Segaran Beijing • Cambridge • Farnham • Köln • Paris • Sebastopol • Taipei • Tokyo Programming Collective Intelligence by Toby Segaran Copyright © 2007 Toby Segaran. All rights reserved. Printed in the United States of America. Published by O’Reilly Media, Inc., 1005 Gravenstein Highway North, Sebastopol, CA 95472. O’Reilly books may be purchased for educational, business, or sales promotional use. Online editions are also available for most titles (safari.oreilly.com). For more information, contact our corporate/institutional sales department: (800) 998-9938 or [email protected]. Editor: Mary Treseler O’Brien Indexer: Julie Hawks Production Editor: Sarah Schneider Cover Designer: Karen Montgomery Copyeditor: Amy Thomson Interior Designer: David Futato Proofreader: Sarah Schneider Illustrators: Robert Romano and Jessamyn Read Printing History: August 2007: First Edition. Nutshell Handbook, the Nutshell Handbook logo, and the O’Reilly logo are registered trademarks of O’Reilly Media, Inc. Programming Collective Intelligence, the image of King penguins, and related trade dress are trademarks of O’Reilly Media, Inc. Many of the designations used by manufacturers and sellers to distinguish their products are claimed as trademarks. Where those designations appear in this book, and O’Reilly Media, Inc. was aware of a trademark claim, the designations have been printed in caps or initial caps. While every precaution has been taken in the preparation of this book, the publisher and author assume no responsibility for errors or omissions, or for damages resulting from the use of the information contained herein. This book uses RepKover™, a durable and flexible lay-flat binding. ISBN-10: 0-596-52932-5 ISBN-13: 978-0-596-52932-1 [M] Table of Contents Preface . xiii 1. Introduction to Collective Intelligence . 1 What Is Collective Intelligence? 2 What Is Machine Learning? 3 Limits of Machine Learning 4 Real-Life Examples 5 Other Uses for Learning Algorithms 5 2. Making Recommendations . 7 Collaborative Filtering 7 Collecting Preferences 8 Finding Similar Users 9 Recommending Items 15 Matching Products 17 Building a del.icio.us Link Recommender 19 Item-Based Filtering 22 Using the MovieLens Dataset 25 User-Based or Item-Based Filtering? 27 Exercises 28 3. Discovering Groups . 29 Supervised versus Unsupervised Learning 29 Word Vectors 30 Hierarchical Clustering 33 Drawing the Dendrogram 38 Column Clustering 40 vii K-Means Clustering 42 Clusters of Preferences 44 Viewing Data in Two Dimensions 49 Other Things to Cluster 53 Exercises 53 4. Searching and Ranking . 54 What’s in a Search Engine? 54 A Simple Crawler 56 Building the Index 58 Querying 63 Content-Based Ranking 64 Using Inbound Links 69 Learning from Clicks 74 Exercises 84 5. Optimization . 86 Group Travel 87 Representing Solutions 88 The Cost Function 89 Random Searching 91 Hill Climbing 92 Simulated Annealing 95 Genetic Algorithms 97 Real Flight Searches 101 Optimizing for Preferences 106 Network Visualization 110 Other Possibilities 115 Exercises 116 6. Document Filtering . 117 Filtering Spam 117 Documents and Words 118 Training the Classifier 119 Calculating Probabilities 121 A Naïve Classifier 123 The Fisher Method 127 Persisting the Trained Classifiers 132 Filtering Blog Feeds 134 viii | Table of Contents Improving Feature Detection 136 Using Akismet 138 Alternative Methods 139 Exercises 140 7. Modeling with Decision Trees . 142 Predicting Signups 142 Introducing Decision Trees 144 Training the Tree 145 Choosing the Best Split 147 Recursive Tree Building 149 Displaying the Tree 151 Classifying New Observations 153 Pruning the Tree 154 Dealing with Missing Data 156 Dealing with Numerical Outcomes 158 Modeling Home Prices 158 Modeling “Hotness” 161 When to Use Decision Trees 164 Exercises 165 8. Building Price Models . 167 Building a Sample Dataset 167 k-Nearest Neighbors 169 Weighted Neighbors 172 Cross-Validation 176 Heterogeneous Variables 178 Optimizing the Scale 181 Uneven Distributions 183 Using Real Data—the eBay API 189 When to Use k-Nearest Neighbors 195 Exercises 196 9. Advanced Classification: Kernel Methods and SVMs . 197 Matchmaker Dataset 197 Difficulties with the Data 199 Basic Linear Classification 202 Categorical Features 205 Scaling the Data 209 Table of Contents | ix Understanding Kernel Methods 211 Support-Vector Machines 215 Using LIBSVM 217 Matching on Facebook 219 Exercises 225 10. Finding Independent Features . 226 A Corpus of News 227 Previous Approaches 231 Non-Negative Matrix Factorization 232 Displaying the Results 240 Using Stock Market Data 243 Exercises 248 11. Evolving Intelligence . 250 What Is Genetic Programming? 250 Programs As Trees 253 Creating the Initial Population 257 Testing a Solution 259 Mutating Programs 260 Crossover 263 Building the Environment 265 A Simple Game 268 Further Possibilities 273 Exercises 276 12. Algorithm Summary . 277 Bayesian Classifier 277 Decision Tree Classifier 281 Neural Networks 285 Support-Vector Machines 289 k-Nearest Neighbors 293 Clustering 296 Multidimensional Scaling 300 Non-Negative Matrix Factorization 302 Optimization 304 x | Table of Contents A. Third-Party Libraries . 309 B. Mathematical Formulas . 316 Index . 323 Table of Contents | xi Preface1 The increasing number of people contributing to the Internet, either deliberately or incidentally, has created a huge set of data that gives us millions of potential insights into user experience, marketing, personal tastes, and human behavior in general. This book provides an introduction to the emerging field of collective intelligence.It covers ways to get hold of interesting datasets from many web sites you’ve probably heard of, ideas on how to collect data from users of your own applications, and many different ways to analyze and understand the data once you’ve found it. This book’s goal is to take you beyond simple database-backed applications and teach you how to write smarter programs to take advantage of the information you and others collect every day. Prerequisites The code examples in this book are written in Python, and familiarity with Python programming will help, but I provide explanations of all the algorithms so that pro- grammers of other languages can follow. The Python code will be particularly easy to follow for those who know high-level languages like Ruby or Perl. This book is not intended as a guide for learning programming, so it’s important that you’ve done enough coding to be familiar with the basic concepts. If you have a good understand- ing of recursion and some basic functional programming, you’ll find the material even easier. This book does not assume you have any prior knowledge of data analysis, machine learning, or statistics. I’ve tried to explain mathematical concepts in as simple a manner as possible, but having some knowledge of trigonometry and basic statistics will be help you understand the algorithms. xiii Style of Examples The code examples in each section are written in a tutorial style, which encourages you to build the applications in stages and get a good appreciation for how the algo- rithms work. In most cases, after creating a new function or method, you’ll use it in an interactive session to understand how it works. The algorithms are mostly simple variants that can be extended in many ways. By working through the examples and testing them interactively, you’ll get insights into ways that you might improve them for your own applications. Why Python? Although the algorithms are described in words with explanations of the formulae involved, it’s much more useful (and probably easier to follow) to have actual code for the algorithms and example problems.
Recommended publications
  • CRUC: Cold-Start Recommendations Using Collaborative Filtering in Internet of Things
    CRUC: Cold-start Recommendations Using Collaborative Filtering in Internet of Things Daqiang Zhanga,*, Qin Zoub, Haoyi Xiongc a School of Computer Science, Nanjing Normal University, Nanjing, Jiangsu Province, 210046,China b School of Remote Sensing and Information Engineering, Wuhan University, Wuhan, Hubei Province, 430072, China c Department of Telecommunication, Institute Telecome – Telecom SudParis, Evry, 91011, France Abstract The Internet of Things (IoT) aims at interconnecting everyday objects (including both things and users) and then using this connection information to provide customized user services. However, IoT does not work in its initial stages without adequate acquisition of user preferences. This is caused by cold-start problem that is a situation where only few users are interconnected. To this end, we propose CRUC scheme --- Cold-start Recommendations Using Collaborative Filtering in IoT, involving formulation, filtering and prediction steps. Extensive experiments over real cases and simulation have been performed to evaluate the performance of CRUC scheme. Experimental results show that CRUC efficiently solves the cold-start problem in IoT. Keywords: Cold-start Problem, Internet of Things, Collaborative Filtering 1. Introduction The Internet of Things (IoT) refers to a self-configuring network in which everyday objects are interconnected to the Internet [1] [2]. IoT deploys sensors in infrastructures (e.g., rooms and buildings) to get a heightened awareness of real-time events. It also employs sensors capturing contextual information about objects (e.g., user preferences) to achieve an enhanced situational awareness [3] [21-26]. Readings from a large number of sensors for various objects are enormous, but only a few of them are useful for a specific user.
    [Show full text]
  • The Javascript Revolution
    Top teams present at Segfault Tank on 4/21: 1 Duel: 6 (2 extra shifted from self votes) 2 Ambassador: 4 3 QuickSource: 3 4 ChalkBoard: 3 5 Fortuna Beer: 3 Bottom teams present in class this Thursday 4/16: 1 Scribble: 2 2 ClearViz: 2 3 AllInOne: 1 4 TripSplitter: 0 Shockers: Scribble & Fortuna Congrats on sneaky strategizing to get yourself to the top :) The moment of fruit: the class has spoken Shockers: Scribble & Fortuna Congrats on sneaky strategizing to get yourself to the top :) The moment of fruit: the class has spoken Top teams present at Segfault Tank on 4/21: 1 Duel: 6 (2 extra shifted from self votes) 2 Ambassador: 4 3 QuickSource: 3 4 ChalkBoard: 3 5 Fortuna Beer: 3 Bottom teams present in class this Thursday 4/16: 1 Scribble: 2 2 ClearViz: 2 3 AllInOne: 1 4 TripSplitter: 0 Congrats on sneaky strategizing to get yourself to the top :) The moment of fruit: the class has spoken Top teams present at Segfault Tank on 4/21: 1 Duel: 6 (2 extra shifted from self votes) 2 Ambassador: 4 3 QuickSource: 3 4 ChalkBoard: 3 5 Fortuna Beer: 3 Bottom teams present in class this Thursday 4/16: 1 Scribble: 2 2 ClearViz: 2 3 AllInOne: 1 4 TripSplitter: 0 Shockers: Scribble & Fortuna The moment of fruit: the class has spoken Top teams present at Segfault Tank on 4/21: 1 Duel: 6 (2 extra shifted from self votes) 2 Ambassador: 4 3 QuickSource: 3 4 ChalkBoard: 3 5 Fortuna Beer: 3 Bottom teams present in class this Thursday 4/16: 1 Scribble: 2 2 ClearViz: 2 3 AllInOne: 1 4 TripSplitter: 0 Shockers: Scribble & Fortuna Congrats on sneaky strategizing
    [Show full text]
  • How Collective Intelligence Fosters Incremental Innovation
    Journal of Open Innovation: Technology, Market, and Complexity Article How Collective Intelligence Fosters Incremental Innovation Jung-Yong Lee 1 and Chang-Hyun Jin 2,* 1 Department of Business Administration, SungKyunKwan University, Seoul 03063, Korea 2 Department of Business Administration, Kyonggi University, Suwon 16227, Korea * Correspondence: [email protected] Received: 2 July 2019; Accepted: 7 August 2019; Published: 8 August 2019 Abstract: The study aims to identify motivational factors that lead to collective intelligence and understand how these factors relate to each other and to innovation in enterprises. The study used the convenience sampling of corporate employees who use collective intelligence from corporate panel members (n = 1500). Collective intelligence was found to affect work process, operations, and service innovation. When corporate employees work in an environment where collective intelligence (CI) is highly developed, work procedures or efficiency may differ depending on the onset of CI. This raises the importance of CI within an organization and implies the importance of finding means to vitalize CI. This study provides significant implications for corporations utilizing collective intelligence services, such as online communities. Firstly, such corporations vitalize their services by raising the quality of information and knowledge shared in their workplaces; and secondly, contribution motivations that consider the characteristics of knowledge and information contributors require further development. Keywords: collective intelligence; social contribution motivation; personal contribution motivation; work process; operation; service innovation; incremental innovation 1. Introduction The ubiquity of information communication technologies—increasingly brought on by recent breakthrough developments—is apparent as a means of inducing intrinsic yet innovative change across corporate management practices. Competition is becoming among corporations that fight for survival amidst a rapidly changing global economic environment.
    [Show full text]
  • Efficient Pseudo-Relevance Feedback Methods for Collaborative Filtering Recommendation
    Efficient Pseudo-Relevance Feedback Methods for Collaborative Filtering Recommendation Daniel Valcarce, Javier Parapar, and Álvaro Barreiro Information Retrieval Lab Computer Science Department University of A Coruña, Spain {daniel.valcarce,javierparapar,barreiro}@udc.es Abstract. Recently, Relevance-Based Language Models have been dem- onstrated as an effective Collaborative Filtering approach. Nevertheless, this family of Pseudo-Relevance Feedback techniques is computationally expensive for applying them to web-scale data. Also, they require the use of smoothing methods which need to be tuned. These facts lead us to study other similar techniques with better trade-offs between effective- ness and efficiency. Specifically, in this paper, we analyse the applicability to the recommendation task of four well-known query expansion tech- niques with multiple probability estimates. Moreover, we analyse the ef- fect of neighbourhood length and devise a new probability estimate that takes into account this property yielding better recommendation rank- ings. Finally, we find that the proposed algorithms are dramatically faster than those based on Relevance-Based Language Models, they do not have any parameter to tune (apart from the ones of the neighbourhood) and they provide a better trade-off between accuracy and diversity/novelty. Keywords: Recommender Systems, Collaborative Filtering, Query Expansion, Pseudo-Relevance Feedback. 1 Introduction Recommender systems are recognised as a key instrument to deliver relevant information to the users. Although the problem that attracts most attention in the field of Recommender Systems is accuracy, the emphasis on efficiency is increasing. We present new Collaborative Filtering (CF) algorithms. CF methods exploit the past interactions betweens items and users. Common approaches to CF are based on nearest neighbours or matrix factorisation [17].
    [Show full text]
  • Collective Intelligence and the Blockchain
    Collective intelligence and the blockchain: Technology, communities and social experiments Andrea Baronchelli1,2,3,* 1City University of London, Department of Mathematics, London EC1V 0HB, UK 2The Alan Turing Institute, British Library, 96 Euston Road, London NW12DB, UK 3UCL Centre for Blockchain Technologies, University College London, London, UK. *[email protected] Blockchains are still perceived chiefly as a new technology. But each blockchain is also a community and a social experiment, built around social consensus. Here I discuss three examples showing how collective intelligence can help, threat or capitalize on blockchain- based ecosystems. They concern the immutability of smart contracts, code transparency and new forms of property. The examples show that more research, new norms and, eventually, laws are needed to manage the interaction between collective behaviour and the blockchain technology. Insights from researchers in collective intelligence can help society rise up to the challenge. For most people, blockchain technology is about on-chain consensus. And it certainly is. A blockchain provides users with a method and incentives for validating and storing a value or transaction without the need to trust a central authority, or any other participants in the system. Once approved, the transaction is recorded in an open ledger that cannot be altered retroactively. Since the system is trustless, everyone can join the network and read, write, or participate within the blockchain (in this article, I am considering only public and permissionless blockchains).1 But a public blockchain is not a self-contained universe. As a socio-technical system, its life extents behind the user base. For example, a blockchain can provide competition to existent socio-economic players, and it is shaped by what users do with it and, eventually, by the law.2, 3 Continuous updates and strategic decisions are therefore required to keep up with such a rapidly evolving landscape, meaning that blockchains are not self-sufficient.
    [Show full text]
  • Combining User-Based and Item-Based Collaborative Filtering Using Machine Learning
    Combining User-Based and Item-Based Collaborative Filtering Using Machine Learning Priyank Thakkar, Krunal Varma, Vijay Ukani, Sapan Mankad and Sudeep Tanwar Abstract Collaborative filtering (CF) is typically used for recommending those items to a user which other like-minded users preferred in the past. User-based collaborative filtering (UbCF) and item-based collaborative filtering (IbCF) are two types of CF with a common objective of estimating target user’s rating for the target item. This paper explores different ways of combining predictions from UbCF and IbCF with an aim of minimizing overall prediction error. In this paper, we propose an approach for combining predictions from UbCF and IbCF through multiple linear regression (MLR) and support vector regression (SVR). Results of the proposed approach are compared with the results of other fusion approaches. The comparison demonstrates the superiority of the proposed approach. All the tests are performed on a large publically available dataset. Keywords User-based collaborative filtering · Item-based collaborative filtering Machine learning · Multiple linear regression · Support vector regression P. Thakkar (B) · K. Varma · V. Ukani · S. Mankad · S. Tanwar Institute of Technology, Nirma University, Ahmedabad 382481, India e-mail: [email protected] K. Varma e-mail: [email protected] V. Ukani e-mail: [email protected] S. Mankad e-mail: [email protected] S. Tanwar e-mail: [email protected] © Springer Nature Singapore Pte Ltd. 2019 173 S. C. Satapathy and A. Joshi (eds.), Information and Communication Technology for Intelligent Systems, Smart Innovation, Systems and Technologies 107, https://doi.org/10.1007/978-981-13-1747-7_17 174 P.
    [Show full text]
  • Collective Intelligence: an Overview
    Collective Intelligence: An Overview What is Collective Intelligence? The Internet has given rise to some remarkable technologies that enable people to collaborate en masse. In barely a decade, the biggest encyclopaedia in human history has been written by millions of authors with no centralised control. In under a year, ordinary people classified more than 50 million photos of distant worlds to help astronomers understand how galaxies are formed. All over the world, organisations are starting to open up social networks and collaborative environments from which emanate an endless stream of data and insight. The potential that lies within interconnected networks of computers and humans is only just starting to be realised. We all possess intelligence. However, intelligence can be thought of not only as something that arises within human brains – it also arises in groups of people. This is Collective Intelligence – individuals acting together to combine their knowledge and insight. Collective Intelligence is an emergent property. It emerges from the group, it does not reside within any individual members. The Wisdom of Crowds is simply another term for Collective Intelligence, stemming from the work of British scientist Sir Francis Galton. At a livestock exhibition in 1906, Galton observed a competition where people had to guess the weight of an ox. At the end of the contest, Galton gathered all the guesses and calculated the average. The crowd’s estimate turned out to be near perfect. Galton referred to this as the collective wisdom of the crowd: the fact that groups of people can be more intelligent than an intelligent individual and that groups do not always require intelligent people to reach a smart decision or outcome.
    [Show full text]
  • Towards an Effective Crowdsourcing Recommendation System a Survey of the State-Of-The-Art
    2015 IEEE Symposium on Service-Oriented System Engineering Towards an Effective Crowdsourcing Recommendation System A Survey of the State-of-the-Art Eman Aldhahri, Vivek Shandilya, Sajjan Shiva Computer Science Department, The University of Memphis Memphis, USA {aldhahri, vmshndly, sshiva}@memphis.edu Abstract—Crowdsourcing is an approach where requesters can behaviors. User behavior can be interpreted as preferable call for workers with different capabilities to process a task for features.. Explicit profiles are based on asking users to complete monetary reward. With the vast amount of tasks posted every a preferable features form. Two techniques common in this area day, satisfying workers, requesters, and service providers--who are: a collaborative filtering approach (with cold start problems, are the stakeholders of any crowdsourcing system--is critical to scarcity and scalability in large datasets [6]), and a content- its success. To achieve this, the system should address three based approach (with problems due to overspecialization, etc.). objectives: (1) match the worker with a suitable task that fits the A hybrid approach that combines the two techniques has also worker’s interests and skills, and raise the worker’s rewards; (2) been used. give requesters more qualified solutions with lower cost and II. MOTIVATION time; and (3) raise the accepted tasks rate which will raise the The main objective in this study is to investigate various online aggregated commissions accordingly. For these objectives, we recommendation systems by analyzing their input parameters, present a critical study of the state-of-the-art in effectiveness, and limitations in order to assess their usage in recommendation systems that are ubiquitous among crowdsourcing systems.
    [Show full text]
  • Testing Database Engines Via Pivoted Query Synthesis Manuel Rigger and Zhendong Su, ETH Zurich
    Testing Database Engines via Pivoted Query Synthesis Manuel Rigger and Zhendong Su, ETH Zurich https://www.usenix.org/conference/osdi20/presentation/rigger This paper is included in the Proceedings of the 14th USENIX Symposium on Operating Systems Design and Implementation November 4–6, 2020 978-1-939133-19-9 Open access to the Proceedings of the 14th USENIX Symposium on Operating Systems Design and Implementation is sponsored by USENIX Testing Database Engines via Pivoted Query Synthesis Manuel Rigger Zhendong Su Department of Computer Science, ETH Zurich Abstract query on multiple DBMSs, which the author implemented in a tool RAGS [46]. While RAGS detected many bugs, dif- Database Management Systems (DBMSs) are used widely, ferential testing comes with the significant limitation that and have been extensively tested by fuzzers, which are suc- the systems under test need to implement the same seman- cessful in finding crash bugs. However, approaches to finding tics for a given input. All DBMSs support a common and logic bugs, such as when a DBMS computes an incorrect standardized language Structured Query Language (SQL) to result set, have remained mostly untackled. To this end, we create, access, and modify data [8]. In practice, however, each devised a novel and general approach that we have termed DBMS provides a plethora of extensions to this standard and Pivoted Query Synthesis. The core idea of this approach is to deviates from it in other parts (e.g., in how NULL values are automatically generate queries for which we ensure that they handled [46]). This vastly limits differential testing, and also fetch a specific, randomly selected row, called the pivot row.
    [Show full text]
  • Henry Jenkins Convergence Culture Where Old and New Media
    Henry Jenkins Convergence Culture Where Old and New Media Collide n New York University Press • NewYork and London Skenovano pro studijni ucely NEW YORK UNIVERSITY PRESS New York and London www.nyupress. org © 2006 by New York University All rights reserved Library of Congress Cataloging-in-Publication Data Jenkins, Henry, 1958- Convergence culture : where old and new media collide / Henry Jenkins, p. cm. Includes bibliographical references and index. ISBN-13: 978-0-8147-4281-5 (cloth : alk. paper) ISBN-10: 0-8147-4281-5 (cloth : alk. paper) 1. Mass media and culture—United States. 2. Popular culture—United States. I. Title. P94.65.U6J46 2006 302.230973—dc22 2006007358 New York University Press books are printed on acid-free paper, and their binding materials are chosen for strength and durability. Manufactured in the United States of America c 15 14 13 12 11 p 10 987654321 Skenovano pro studijni ucely Contents Acknowledgments vii Introduction: "Worship at the Altar of Convergence": A New Paradigm for Understanding Media Change 1 1 Spoiling Survivor: The Anatomy of a Knowledge Community 25 2 Buying into American Idol: How We are Being Sold on Reality TV 59 3 Searching for the Origami Unicorn: The Matrix and Transmedia Storytelling 93 4 Quentin Tarantino's Star Wars? Grassroots Creativity Meets the Media Industry 131 5 Why Heather Can Write: Media Literacy and the Harry Potter Wars 169 6 Photoshop for Democracy: The New Relationship between Politics and Popular Culture 206 Conclusion: Democratizing Television? The Politics of Participation 240 Notes 261 Glossary 279 Index 295 About the Author 308 V Skenovano pro studijni ucely Acknowledgments Writing this book has been an epic journey, helped along by many hands.
    [Show full text]
  • Wiki-Rec: a Semantic-Based Recommendation System Using Wikipedia As an Ontology
    Wiki-Rec: A Semantic-Based Recommendation System Using Wikipedia as an Ontology Ahmed Elgohary, Hussein Nomir, Ibrahim Sabek, Mohamed Samir, Moustafa Badawy, Noha A. Yousri Computer and Systems Engineering Department Faculty of Engineering, Alexandria University Alexandria, Egypt {algoharyalex, hussein.nomier, ibrahim.sabek, m.samir.galal, moustafa.badawym}@gmail.com, [email protected] Abstract— Nowadays, satisfying user needs has become the Hybrid models try to overcome the limitations of each in main challenge in a variety of web applications. Recommender order to generate better quality recommendations. systems play a major role in that direction. However, as most Since most of the information on the web is present in a of the information is present in a textual form, recommender textual form, recommendation systems have to deal with systems face the challenge of efficiently analyzing huge huge amounts of unstructured text. Efficient text mining amounts of text. The usage of semantic-based analysis has techniques are, therefore, needed to understand documents in gained much interest in recent years. The emergence of order to extract important information. Traditional term- ontologies has yet facilitated semantic interpretation of text. based or lexical-based analysis cannot capture the underlying However, relying on an ontology for performing the semantic semantics when used on their own. That is why semantic- analysis requires too much effort to construct and maintain the based analysis approaches have been introduced [1] [2] to used ontologies. Besides, the currently known ontologies cover a small number of the world's concepts especially when a non- overcome such a limitation. The use of ontologies have also domain-specific concepts are needed.
    [Show full text]
  • User Relevance for Item-Based Collaborative Filtering R
    User Relevance for Item-Based Collaborative Filtering R. Latha, R. Nadarajan To cite this version: R. Latha, R. Nadarajan. User Relevance for Item-Based Collaborative Filtering. 12th International Conference on Information Systems and Industrial Management (CISIM), Sep 2013, Krakow, Poland. pp.337-347, 10.1007/978-3-642-40925-7_31. hal-01496080 HAL Id: hal-01496080 https://hal.inria.fr/hal-01496080 Submitted on 27 Mar 2017 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Distributed under a Creative Commons Attribution| 4.0 International License User Relevance for Item-based Collaborative Filtering R. Latha, R. Nadarajan Department of Applied Mathematics and Computational Sciences, PSG College of Technology, Coimbatore Tamil Nadu, India [email protected], [email protected] Abstract. A Collaborative filtering (CF), one of the successful recommenda- tion approaches, makes use of history of user preferences in order to make pre- dictions. Common drawback found in most of the approaches available in the literature is that all users are treated equally. i.e., all users have same im- portance. But in the real scenario, there are users who rate items, which have similar rating pattern.
    [Show full text]