Samhaa R. El-Beltagy, Wendy Hall, David De Roure, and Leslie Carr Intelligence, Agents, Multimedia Department of Electronics and Computer Science University of Southampton LINKING IN CONTEXT

Motivation The need to assist users in their information finding activities while taking their local context into consideration

Goal zAdapt to the information needs of a community of users and assist them based on their individual needs Explore the idea of dynamically adding links to Web pages, based on the context of the pages and users, as a way of assisting Web users in their information finding and navigation activities

Open Hypermedia are first class citizens managed separately from the documents can be generic, linking arbitrary objects In Open Hypermedia, links: Customized hypermedia documents Documents in native format Open Hypermedia Hypermedia Link database

A Web based proxy model browse http request Proxy Active linkbase The Web Requested Web page Requested Web page + added links

The DLS model zUsers select from available linkbases zLimitations yLinks have to be manually pre-authored yLinking is performed based on the currently selected linkbase regardless of the context

Extending the model zAutomatically switch between linkbases according to the context of documents zEnable automatic creation of links to populate linkbases

Links in context: An Example Links related to the presented document are rendered based on the document’s context. A link is re-presented as a query that is resolved when the user follows it

‘Bush’ in a different context The system resolves a different context for this document and accordingly different links for ‘bush’ are suggested.

Issues involved zDetecting user interests zAutomatically generating links that fit the dynamically detected user interests zMaking generated links available to interested users only, and displaying those links in their appropriate context zManaging the life cycle of generated links

Detecting a user’s interests? zMonitor his/her browsing and bookmarking activities and use that to build a profile!

Generate links that fit the detected users’ interests? zUse documents that a user has found interesting to generate links zHave the UI agent ‘tell’ the agent responsible for link generation about documents its user has found interesting

Link Generation zA difficult problem, thus we’ve resolved to link re-use zBasic premise: If document X and document Y appear in context Z, and there is a link related to a concept C in document X, then the same link can be applied to concept C in document Y. This applies to all documents in context Z.

Representing interest profiles and contexts zEach document is represented by a vector calculated using the TF-IDF technique zIncoming documents are grouped into various clusters, representing various contexts depending on the similarity of their content zVarious contexts are each represented by a single vector under which created links are grouped depending on their context

Obtaining links and rendering them in appropriate contexts? zHave the UI agent subscribe to the Link extraction agent for links that are relevant to its user’s interests zStore the links under a given context using the interest representations

The Scenario zUser interface agent builds a user profile by monitoring bookmarking, browsing and searching activities zProfile determines contexts of user’s interests which are used subscription to links in ‘context’ zLinks are cached in personal linkbases and rendered based on document context

The Evaluation experiment zGoal: to study the implications of dynamically creating and adding links in their proper contexts on the process of locating information

The Experiment z In the first phase y2 groups of users answer two different sets of question revolving around the private life of Vannevar Bush and some basic technical questions about CORBA respectively using only a search engine zIn the second phase ythe 2 groups swap tasks and each group answers the questions using a search engine + links added by the system to pages they are browsing

Examples of created source anchors z In the context of Vannevar Bush: xMemex, Vannevar Bush, Vannevar, Bush, MIT, timeline, As We May Think, Profile Tracer, Differential Analyzer, 1945  In the context of George W. Bush: xGeorge, Bush, President, Laura Welch Bush, Laura, Welch, Governor Bush, Texas, photo gallery, Presidency, News  In the context of CORBA: xDistributed Applications, CORBA, OMG, ORB, Distributed Objects, Objects, IDL Interfaces, IDL, Object References, CORBA Architecture

Evaluation Results zOn average, users using the linking facility completed their task in 28% of the time taken by users employing a search engine only for the CORBA task and in 55% of the time taken by users using a search engine only for the Bush task

Conclusions zLinks created as a result of employing information found useful by one user navigating the information space, can guide other users to information sources that can otherwise be difficult to locate when presented as targeted recommendations specific to certain concepts in a document  One advantage of offering context links is that the user does not even have to think of what query to enter

Future work zAllowing users to control the contents of their own linkbases zGetting user feedback on recommended documents zInvestigating the use of natural language techniques in link phrase extraction zExperimenting with ways of achieving a more localized level of contextualization

Questions