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Communications of the Acm COMMUNICATIONS CACM.ACM.ORG OF THEACM 11/2014 VOL.57 NO.11 Scene Understanding by Labeling Pixels Evolution of the Product Manager The Data on Diversity On Facebook, Most Ties Are Weak Keeping Online Reviews Honest Association for Computing Machinery tvx-full-page.pdf-newest.pdf 1 11/10/2013 12:03 3-5 JUNE, 2015 BRUSSELS, BELGIUM Course and Workshop C proposals by M 15 November 2014 Y CM Paper Submissions by MY 12 January 2015 CY CMY K Work in Progress, Demos, DC, & Industrial Submissions by 2 March 2015 Welcoming Submissions on Content Production Systems & Infrastructures Devices & Interaction Techniques Experience Design & Evaluation Media Studies Data Science & Recommendations Business Models & Marketing Innovative Concepts & Media Art TVX2015.COM [email protected] ACM Books M MORGAN& CLAYPOOL &C PUBLISHERS Publish your next book in the ACM Digital Library ACM Books is a new series of advanced level books for the computer science community, published by ACM in collaboration with Morgan & Claypool Publishers. I’m pleased that ACM Books is directed by a volunteer organization headed by a dynamic, informed, energetic, visionary Editor-in-Chief (Tamer Özsu), working closely with a forward-looking publisher (Morgan and Claypool). —Richard Snodgrass, University of Arizona books.acm.org ACM Books ◆ will include books from across the entire spectrum of computer science subject matter and will appeal to computing practitioners, researchers, educators, and students. ◆ will publish graduate level texts; research monographs/overviews of established and emerging fields; practitioner-level professional books; and books devoted to the history and social impact of computing. ◆ will be quickly and attractively published as ebooks and print volumes at affordable prices, and widely distributed in both print and digital formats through booksellers and to libraries and individual ACM members via the ACM Digital Library platform. ◆ is led by EIC M. Tamer Özsu, University of Waterloo, and a distinguished editorial board representing most areas of CS. Proposals and inquiries welcome! Association for Contact: M. Tamer Özsu, Editor in Chief Computing Machinery [email protected] Advancing Computing as a Science & Profession COMMUNICATIONS OF THE ACM Departments News Viewpoints 5 From the President 24 Economic and Business Dimensions Dealing with the Deep, Long-Term The Dark Side of the Sharing Challenges Facing ACM (Part I) Economy … and How to Lighten It By Alexander L. Wolf Improving the sharing economy will require addressing myriad problems. 7 Cerf’s Up By Arvind Malhotra Heidelberg Laureate Forum II and Marshall Van Alstyne By Vinton G. Cerf 28 Legally Speaking 9 Letters to the Editor Updates on the Intellectual Accountability Is No Excuse Property Front for Surveillance Recapping influential U.S. Supreme Court decisions 10 BLOG@CACM rendered earlier this year. Teach the Teachers, 16 By Pamela Samuelson and Contribute to Humanity Mark Guzdial suggests computer 13 Researchers Simplify 31 Computing Ethics science education needs to be Parallel Programming Big Data’s End Run Around aimed at adults before teaching it to Parallel computing has become Procedural Privacy Protections children; Lawrence M. Fisher finds increasingly important as Recognizing the inherent limitations the volunteer spirit behind ACM chipmakers put more and more of consent and anonymity. Special Interest Groups. processor cores on individual chips. By Solon Barocas and Helen Nissenbaum By Gary Anthes 41 Calendar 34 Education 16 Computing What Fits A Future for Computing 106 Careers New apps and pods improve Education Research the virtual and actual retail Seeking to address the most experiences by ensuring clothing important issues facing the computer Last Byte and cosmetics look good on you education research community. before you buy them. By Steve Cooper, Shuchi Grover, 120 Upstart Puzzles By Esther Shein Mark Guzdial, and Beth Simon Proving without Teaching/ Teaching without Proving 20 Keeping Online Reviews Honest 37 Privacy and Security By Dennis Shasha As online reviews become Summing Up increasingly important Considering recent privacy- and security- to e-commerce and social media related events through this column. sites, computer scientists By Susan Landau work on ways to ensure their authenticity. 40 Viewpoint By Logan Kugler An Embarrassment of Riches A critical review of open innovation systems. By Mark Klein and Gregorio Convertino 43 Viewpoint Designing User Incentives for Cybersecurity How to encourage better user security practices and behavior. Association for Computing Machinery Advancing Computing as a Science & Profession By Terrence August, Robert August, and Hyoduk Shin OF BODYMETRICS COURTESY IMAGE 2 COMMUNICATIONS OF THE ACM | NOVEMBER 2014 | VOL. 57 | NO. 11 11/2014 VOL. 57 NO. 11 Practice Contributed Articles Review Articles 48 68 86 48 Evolution of the Product Manager 68 Scene Understanding 86 The Data on Diversity Better education needed by Labeling Pixels It’s not just about being fair. to develop the discipline. Pixels labeled with a scene’s By Beryl Nelson By Ellen Chisa semantics and geometry let computers describe what they see. 53 JavaScript and the Netflix By Stephen Gould and Xuming He Research Highlights User Interface Conditional dependency resolution. 78 On Facebook, Most Ties Are Weak 97 Technical Perspective By Alex Liu Strong ties connect individuals The Intricate Dance in the same community; of Fabric and Light 60 A Decade of Progress in Parallel weak ties connect individuals By Szymon Rusinkiewicz Programming Productivity in different communities. Looking at the design By Pasquale De Meo, 98 Building Volumetric Appearance and benefits of X10. Emilio Ferrara, Giacomo Fiumara, Models of Fabric Using By John T. Richards, Jonathan Brezin, and Alessandro Provetti Micro CT Imaging Calvin B. Swart, and By Shuang Zhao, Wenzel Jakob, Christine A. Halverson Steve Marschner, and Kavita Bala Articles’ development led by queue.acm.org About the Cover: Creating a computer that can automatically understand a visual scene has been a perennial problem in the AI and computer vision fields. This month’s cover story (p. 68) presents a promising approach that calls for annotating every pixel in a scene with a label that indicates what and where it is. Cover illustration by MEME IMAGE BY CATHERINE CONSTANTINIDES/ONEDESK.COM; ILLUSTRATIONS BY ANDREW JOYCE, SARAH HANSON SARAH ANDREW JOYCE, BY ILLUSTRATIONS CONSTANTINIDES/ONEDESK.COM; CATHERINE BY MEME IMAGE Andrew Joyce. NOVEMBER 2014 | VOL. 57 | NO. 11 | COMMUNICATIONS OF THE ACM 3 COMMUNICATIONS OF THE ACM Trusted insights for computing’s leading professionals. Communications of the ACM is the leading monthly print and online magazine for the computing and information technology fields. Communications is recognized as the most trusted and knowledgeable source of industry information for today’s computing professional. Communications brings its readership in-depth coverage of emerging areas of computer science, new trends in information technology, and practical applications. Industry leaders use Communications as a platform to present and debate various technology implications, public policies, engineering challenges, and market trends. The prestige and unmatched reputation that Communications of the ACM enjoys today is built upon a 50-year commitment to high-quality editorial content and a steadfast dedication to advancing the arts, sciences, and applications of information technology. ACM, the world’s largest educational STAFF EDITORIAL BOARD ACM Copyright Notice and scientific computing society, delivers Copyright © 2014 by Association for resources that advance computing as a DIRECTOR OF GROUP PUBLISHING EDITOR-IN-CHIEF Computing Machinery, Inc. (ACM). science and profession. ACM provides the Scott E. Delman Moshe Y. Vardi Permission to make digital or hard copies computing field’s premier Digital Library [email protected] [email protected] of part or all of this work for personal and serves its members and the computing Executive Editor NEWS or classroom use is granted without profession with leading-edge publications, Diane Crawford Co-Chairs fee provided that copies are not made conferences, and career resources. Managing Editor William Pulleyblank and Marc Snir or distributed for profit or commercial Thomas E. Lambert Board Members advantage and that copies bear this Executive Director and CEO Senior Editor Mei Kobayashi; Kurt Mehlhorn; notice and full citation on the first John White Andrew Rosenbloom Michael Mitzenmacher; Rajeev Rastogi page. Copyright for components of this Deputy Executive Director and COO Senior Editor/News work owned by others than ACM must Patricia Ryan Larry Fisher VIEWPOINTS be honored. Abstracting with credit is Director, Office of Information Systems Web Editor Co-Chairs permitted. To copy otherwise, to republish, Wayne Graves David Roman Tim Finin; Susanne E. Hambrusch; to post on servers, or to redistribute to Director, Office of Financial Services Editorial Assistant John Leslie King lists, requires prior specific permission Darren Ramdin Zarina Strakhan Board Members and/or fee. Request permission to publish Director, Office of SIG Services Rights and Permissions William Aspray; Stefan Bechtold; from [email protected] or fax Donna Cappo Deborah Cotton Michael L. Best; Judith Bishop; (212) 869-0481. Director, Office of Publications Stuart I. Feldman; Peter Freeman; Bernard Rous Art Director Mark Guzdial; Rachelle Hollander; For other copying of
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