Web Data Management Powering the New Web Raghu

Web Data Management: Powering the New Web Raghu Ramakrishnan Chief Scientist for Audience, Yahoo! Research Fellow, Yahoo! Research (On leave, Univ. of Wisconsin-Madison)

Outline • Trends in Search and Information Discovery – Move towards task-centricity – Need to interpret content • Evolution of Online Communities – Social Search – People. Web – Community Information Management – Heterogeneous content Research -2 -

Further Reading • Content, Metadata, and Behavioral Information: Directions for Yahoo! Research, The Yahoo! Research Team, IEEE Data Engineering Bulletin, Dec 2006 (Special Issue on Web-Scale Data, Systems, and Semantics) • Systems, Communities, Community Systems, on the Web, Community Systems Group at Yahoo! Research, SIGMOD Record, Sept 2007 • Towards a People. Web, R. Ramakrishnan and A. Tomkins, IEEE Computer, August 2007 (Special Issue on Web Search) Research -4 -

Community Systems Group @ Yahoo! Research Philip Bohannon Brian Cooper Nilesh Dalvi Minos Garofalakis Hans-Arno Jacobsen Vinay Kakade Dan Kifer Raghu Ramakrishnan Adam Silberstein Utkarsh Srivastava Ramana Yerneni Cong Yu Research Deepak Agrawal Sihem Amer-Yahia Ravi Kumar Cameron Marlow Srujana Merugu Chris Olston Bo Pang Ben Reed Keerthi Selvaraj Jai Shanmugasundaram Andrew Tomkins -5 - Parag Agrawal Tyson Condie Pedro De. Rose Alban Galland Nitin Gupta Ashwin Machanavajjhala Warren Shen Julia Stoyanovich Fan Yang

Trends in Search

Structure Intent “seafood san francisco” Category: restaurant Location: San Francisco Reserve a table for two tonight at SF’s best Sushi Bar and get a free sake, compliments of Open. Table! Category: restaurant Location: San Francisco Alamo Square Seafood Grill (415) 440 -2828 803 Fillmore St, San Francisco, CA - 0. 93 mi - map Category: restaurant Location: San Francisco Research -7 -

Y! Shortcuts Research -8 -

Google Base Research -9 -

Supplying Structured Search Content • Semantic Web? • Unleash community computing—People. Web! • Three ways to create semantically rich summaries that address the user’s information needs: – Editorial, Extraction, UGC Challenge: Design social interactions that lead to creation and maintenance of high-quality structured content Research - 10 -

Search and Content Supply • Premise: – People don’t want to search – People want to get tasks done Start Research I want to book a vacation in Tuscany. Broder 2002, A Taxonomy of web search - 11 - Finish

Social Search • Improve web search by – Learning from shared community interactions, and leveraging community interactions to create and refine content • Enhance and amplify user interactions – Expanding search results to include sources of information (e. g. , experts, sub-communities of shared interest) Reputation, Quality, Trust, Privacy Research - 12 -

Evolution of Online Communities

Rate of content creation • Estimated growth of content – Published content from traditional sources: 3 -4 Gb/day – Professional web content: ~2 Gb/day – User-generated content: 8 -10 Gb/day – Private text content: ~3 Tb/day (200 x more) – Upper bound on typed content: ~700 Tb/day Research - 14 -

Metadata • Estimated growth of metadata – Anchortext: 100 Mb/day – Tags: 40 Mb/day Drove most advances in search from 1996 -present – Pageviews: 100 -200 Gb/day – Reviews: Around 10 Mb/day – Ratings: <small> Increasingly rich and available, but not yet useful in search This is in spite of the fact that interactions on the web are currently limited by the fact that each site is essentially a silo Research - 15 -

People. Web: Site-Centric Global Object Model Community Search People-Centric Portable Social Environment • Common web-wide id for objects (incl. users) – Even common attributes? (e. g. , pixels for camera objects) • As users move across sites, their personas and social networks will be carried along • Increased semantics on the web through community activity (another path to the goals of the Semantic Web) (Towards a People. Web, Ramakrishnan & Tomkins, IEEE Computer, August 2007) Research - 16 -

Facebook Apps, Open Social • Web site provides canvas – Third party apps can paint on this canvas – “Paint” comes from data on and off-network • Via APIs that each site chooses to expose What is the core asset of a web portal? • What are the computational implications? – App hosting and caching – Dynamic, personalized content – Searching over “spaghetti” information threads Research - 17 -

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Web Search Results for “Lisa” Latest news results for “Lisa”. Mostly about people because Lisa is a popular name 41 results from My Web! Web search results are very diversified, covering pages about organizations, projects, people, events, etc. Research - 19 -

Save / Tag Pages You Like Enter your note for personal recall and sharing purpose You can save / tag pages you like into My Web from toolbar / bookmarklet / save buttons You can pick tags from the suggested tags based on collaborative tagging technology Type-ahead based on the tags you have used You can specify a sharing mode You can save a cache copy of the page content Research (Courtesy: Raymie Stata) - 20 -

My Web 2. 0 Search Results for “Lisa” Excellent set of search results from my community because a couple of people in my community are interested in Usenix Lisarelated topics Research - 21 -

Google Co-Op Query-based direct-display, programmed by Contributor This query matches a pattern provided by Contributor… …so SERP displays (queryspecific) links programmed by Contributor. Subscribed Link edit | remove Users “opts-in” by “subscribing” to them Research - 22 -

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Tech Support at COMPAQ “In newsgroups, conversations disappear and you have to ask the same question over and over again. The thing that makes the real difference is the ability for customers to collaborate and have information be persistent. That’s how we found QUIQ. It’s exactly the philosophy we’re looking for. ” “Tech support people can’t keep up with generating content and are not experts on how to effectively utilize the product … Mass Collaboration is the next step in Customer Service. ” – Steve Young, VP of Customer Care, Compaq Research - 24 -

How It Works Customer QUESTION SELF SERVICE Answer added to power self service ANSWER KNOWLEDGE BASE -Partner Experts - Customer Champions -Employees Support Agent Research - 25 -

Timely Answers 77% of answers provided within 24 h 6, 845 86% (4, 328) • No effort to answer each question • No added experts • No monetary incentives for enthusiasts 74% 77% (3, 862) answered 65% (3, 247) 40% (2, 057) Answers provided in 3 h Research Answers provided in 12 h in 24 h Answers provided in 48 h Questions - 26 -

Power of Knowledge Creation SUPPORT SHIELD 1 ~80% SHIELD 2 Self. Service *) Knowledge Creation Customer Mass Collaboration 5 -10 % Support Incidents Agent Cases *) Averages from QUIQ implementations Research - 27 - *)

Mass Contribution Users who on average provide only 2 answers provide 50% of all answers Answers 100 % (6, 718) Contributed by mass of users 50 % (3, 329) Top users Contributing Users 7 % (120) Research 93 % (1, 503) - 28 -

Interesting Problems • Question categorization • Detecting undesirable questions & answers • Identifying “trolls” • Ranking results in Answers search • Finding related questions • Estimating question & answer quality (Byron Dom: SIGIR talk) Research - 29 -

Better Search via Information Extraction • Extract, then exploit, structured data from raw text: For years, Microsoft Corporation CEO Bill Gates was against open source. But today he appears to have changed his mind. "We can be open source. We love the concept of shared source, " said Bill Veghte, a Microsoft VP. "That's a super-important shift for us in terms of code access. “ Richard Stallman, founder of the Free Software Foundation, countered saying… Research Select Name From PEOPLE Where Organization = ‘Microsoft’ PEOPLE Name Bill Gates Bill Veghte Richard Stallman Title Organization CEO Microsoft VP Microsoft Founder Free Soft. . Bill Gates Bill Veghte - 30 - (from Cohen’s IE tutorial, 2003)

Community Information Management (CIM) • Many real-life communities have a Web presence – Database researchers, movie fans, stock traders • Each community = many data sources + people • Members want to query and track at a semantic level: – Any interesting connection between researchers X and Y? – List all courses that cite this paper – Find all citations of this paper in the past one week on the Web – Research. What is new in the past -24 hours in the database - 31

DBLife § Integrated information about a (focused) realworld community § Collaboratively built and maintained by the community § Semantic web via extraction & community Research - 32 -

DBLife • Faculty: An. Hai Doan & Raghu Ramakrishnan • Students: P. De. Rose, W. Shen, F. Chen, R. Mc. Cann, Y. Lee, M. Sayyadian • Prototype system up and running since early 2005 • Plan to release a public version of the system in Spring 2007 • 1164 sources, crawled daily, 11000+ pages / day • 160+ MB, 121400+ people mentions, 5600+ persons • See DE overview article, CIDR 2007 demo Research - 33 -

DBLife Papers • • Efficient Information Extraction over Evolving Text Data, F. Chen, A. Doan, J. Yang, R. Ramakrishnan. ICDE-08. Building Structured Web Community Portals: A Top-Down, Compositional, and Incremental Approach, P. De. Rose, W. Shen, F. Chen, A. Doan, R. Ramakrishnan. VLDB 07. Declarative Information Extraction Using Datalog with Embedded Extraction Predicates, W. Shen, A. Doan, J. Naughton, R. Ramakrishnan. VLDB-07. Source-aware Entity Matching: A Compositional Approach, W. Shen, A. Doan, J. F. Naughton, R. Ramakrishnan: ICDE 2007. OLAP over Imprecise Data with Domain Constraints, D. Burdick, A. Doan, R. Ramakrishnan, S. Vaithyanathan. VLDB-07. Community Information Management, A. Doan, R. Ramakrishnan, F. Chen, P. De. Rose, Y. Lee, R. Mc. Cann, M. Sayyadian, and W. Shen. IEEE Data Engineering Bulletin, Special Issue on Probabilistic Databases, 29(1), 2006. Managing Information Extraction, A. Doan, R. Ramakrishnan, S. Vaithyanathan. SIGMOD -06 Tutorial. Research - 34 -

DBLife • Integrate data of the DB research community • 1164 data sources Crawled daily, 11000+ pages = 160+ MB / day Research - 35 -

Entity Extraction and Resolution co-authors = A. Doan, Divesh Srivastava, . . . Raghu Ramakrishnan Research - 36 -

Resulting ER Graph “Proactive Re-optimization write Shivnath Babu advise coauthor write coauthor Jennifer Widom David De. Witt PC-member PC-Chair SIGMOD 2005 Research Pedro Bizarro - 37 - advise

Challenges • Extraction – Domain-level vs. site-level extraction “templates” • Compositional, customizable approach to extraction planning – Blending extraction with other sources (feeds, wiki-style user edits) • Maintenance of extracted information – Managing information Extraction – Incremental maintenance of “extracted views” at large scales – Mass Collaboration—community-based maintenance • Exploitation – Search/query over extracted structures in a community – Search across communities—Semantic Web through the back door! – Detect interesting events and changes Research - 38 -

Example Entity Resolution Plans d 1: Gravano’s Homepage d 2: Columbia DB Group Page L. Gravano, K. Ross. Text Databases. SIGMOD 03 L. Gravano, J. Sanz. Packet Routing. SPAA 91 union d 1 d 2 Research J. L. Gravano, J. Zhou. Text Retrieval. VLDB 04 C. Li. Machine Learning. AAAI 04 union d 3 K. Ross d 4: Chen Li’s Homepage s 1 s 0 Members L. Gravano Zhou s 0 d 4 C. Li, A. Tung. Entity Matching. KDD 03 d 3: DBLP Luis Gravano, Kenneth Ross. Digital Libraries. SIGMOD 04 Luis Gravano, Jingren Zhou. Fuzzy Matching. VLDB 01 Luis Gravano, Jorge Sanz. Packet Routing. SPAA 91 Chen Li, Anthony Tung. Entity Matching. KDD 03 Chen Li, Chris Brown. Interfaces. HCI 99 s 0 matcher: Two mentions match if they share the same name. s 1 matcher: Two mentions match if they share the same name and at least one co-author name. - 39 -

Continuous Entity Resolution • What if Entity/Link database is continuously updated to reflect changes in the real world? (E. g. , Web crawls of user home pages) • Can use the fact that few pages are new (or have changed) between updates. Challenges: • How much belief in existing entities and links? • Efficient organization and indexing – Where there is no meaningful change, recognize this and minimize repeated work Research - 40 -

Continuous ER and Event Detection • The real world might have changed! – And we need to detect this by analyzing changes in extracted information Affiliated-with Yahoo! Research Raghu Ramakrishnan University of Affiliated-with Gives-tutorial Wisconsin Raghu Ramakrishnan Gives-tutorial Research SIGMOD-06 - 41 - SIGMOD-06

Mass Collaboration • We want to leverage user feedback to improve the quality of extraction over time. – Maintaining an extracted “view” on a collection of documents over time is very costly; getting feedback from users can help – In fact, distributing the maintenance task across a large group of users may be the best approach Research - 42 -

Mass Collaboration: A Simplified Example Not David! Picture is removed if enough users vote “no”. Research - 43 -

Mass Collaboration Meets Spam Jeffrey F. Naughton swears that this is David J. De. Witt Research - 44 -

Incorporating Feedback A. Gupta, D. Smith, Text mining, SIGMOD-06 System extracted “Gupta, D” as a person name User says this is wrong System extracted “Gupta, D” using rules: Knowing this, system can potentially improve extraction accuracy. (R 1) David Gupta is a person name (R 2) If “first-name last-name” is a person name, then “last-name, f” is also a person name. (1) Discover corrective rules (2) Find and fix other incorrect applications of R 1 and R 2 A general framework for incorporating feedback? Research - 45 -

Collaborative Editing • Users should be able to – Correct/add to the imported data – E. g. , User imports a paper, system provides bib item • Challenges – Incentives, reputation – Handling malicious/spam users – Ownership model • My home page vs. a citation that appears on it – Reconciliation • Extracted vs. manual input Research - 46 -

Understanding Extracted Information • The extraction process is riddled with errors – How should these errors be represented? – Individual annotators are black-boxes with an internal probability model and typically output only the probabilities. While composing annotators how should their combined uncertainty be modeled? • Lots of work – Fuhr-Rollecke; Imielinski-Lipski; Prob. View; Halpern; … – Recent: See March 2006 Data Engineering bulletin for special issue on probabilistic data management (includes Green-Tannen survey) – Tutorials: Dalvi-Suciu Sigmod 05, Halpern PODS 06 Research - 47 -

Understanding Extracted Information • Users want to “drill down” on extracted data – We need to be able to explain the basis for an extracted piece of information when users “drill down”. – Many proof-tree based explanation systems built in deductive DB / LP /AI communities (Coral, LDL, EKS-V 1, XSB, Mc. Guinness, …) – Studied in context of provenance of integrated data (Buneman et al. ; Stanford warehouse lineage, and more recently Trio) • But … concisely explaining complex extractions (e. g. , using statistical models, workflows, and reflecting uncertainty) is hard – And especially useful because users are likely to drill down when they are surprised or confused by extracted data (e. g. , due to errors, uncertainty). Research - 48 -

Provenance and Collaboration • Provenance/lineage/explanation becomes a key issue if we want to leverage user feedback to improve the quality of extraction over time. – Explanations must be succint, from end-user perspective —not from derivation perspective – Maintaining an extracted “view” on a collection of documents over time is very costly; getting feedback from users can help – In fact, distributing the maintenance task across a large group of users may be the best approach Research - 49 -

Provenance, Explanations A. Gupta, D. Smith, Text mining, SIGMOD-06 Incorrect. But why? System extracted “Gupta, D” as a person name reference System extracted “Gupta, D” using these rules: (R 1) David Gupta is a person name (R 2) If “first-name last-name” is a person name, then “last-name, f” is also a person name. Knowing this, system builder can potentially improve extraction accuracy. One way to do that: (S 1) Detect a list of items (S 2) If A straddles two items in a list A is not a person name Research - 50 -

The Purple SOX Project (SOcial e. Xtraction) Application Layer Shopping, Travel, Autos Academic Portals (DBLife/Me Yahoo) Enthusiast Platform …and many others Extraction Management System (e. g Vertex, Societek) Operator Library Research - 51 -

Extraction Management System Goals: 50, 000 -foot view • Support Scalable and Social Information Extraction • “Scalable” in the Extraction Management System – number and kind of operators – number and kind of applications – data and processing (commodity hardware) • “Social” in that community input is solicited to – define the goals of the application—customizability – bootstrap information extraction with examples of various kinds – refine information extraction with quality feedback Research - 52 -

Operator Library Goals: 10, 000 foot view • Provide high quality operators for common extraction tasks under realistic settings for a variety of domains – record extraction, entity deduping, relation extraction – different levels and types of supervision, transfer across domains, active/passive modes – academic extraction, local search, etc. Operator Library • Build core infrastructure for creation & deployment of PSOX operators – feature engine, evaluation engine – assembling existing resources • Develop and evaluate fundamentally new methods over target domains – semi-supervised, active & transfer learning approaches Research - 53 -

Web Data Management: Massively Distributed Hosted Systems

An Example Web App Heavy use of simple database operations Updates tags uploads as “flower” Queries » Your Photos » Photos tagged as “flower” » Friend activity Sonja uploaded Brandon tagged a photo Research - 56 -

The Problem What does it take to build the next big app? Research - 57 -

Why Hosted? simple API § No maintenance worries for application § Single ops team § Resource sharing leads to savings Research - 59 -

The PNUTS Project A B C D E F 42342 42521 66354 12352 75656 15677 A B C D E F E W W E CREATE TABLE Parts ( ID VARCHAR, Stock. Number INT, Status VARCHAR A 42342 E … B 42521 W ) C 66354 W D E F Research 12352 75656 15677 - 61 - E C E 42342 42521 66354 12352 75656 15677 E W W E C E

Summary • Online communities represent a tremendous resource for organizing information online – Extraction + mass collaboration = semantics • Web is becoming – More people-centric, less site-centric – Highly intertwined, distributed, dynamic, personalized – Models of ownership, trust, incentives? – Next generation of search algorithms and infrastructure? Research - 72 -