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Samhaa R. El-Beltagy, Wendy Hall, David De Roure, and Leslie Carr
Intelligence, Agents, MultimediaIntelligence, Agents, Multimedia
Department of Electronics and Computer Science Department of Electronics and Computer Science
University of SouthamptonUniversity of Southampton
LINKING IN CONTEXT
Motivation
The need to assist users in their information finding activities while taking their local context into consideration
Goal
Adapt 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 Customized hypermedia hypermedia documentsdocuments
Documents in native format
Open HypermediaOpen 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
Users select from available linkbases
Limitations Links have to be manually pre-authored Linking is performed based on the currently selected
linkbase regardless of the context
Extending the model
Automatically switch between linkbases according to the context of documents
Enable automatic creation of links to populate linkbases
Links in context: An Example
Links related to the presented document are renderedbased 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 documentand accordingly differentlinks for ‘bush’ are suggested.
Issues involved
Detecting user interestsAutomatically generating links that fit the
dynamically detected user interestsMaking generated links available to
interested users only, and displaying those links in their appropriate context
Managing the life cycle of generated links
Detecting a user’s interests?
Monitor his/her browsing and bookmarking activities and use that to build a profile!
Generate links that fit the detected users’ interests?
Use documents that a user has found interesting to generate links
Have the UI agent ‘tell’ the agent responsible for link generation about documents its user has found interesting
Link Generation
A difficult problem, thus we’ve resolved to link re-use
Basic 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
Each document is represented by a vector calculated using the TF-IDF technique
Incoming documents are grouped into various clusters, representing various contexts depending on the similarity of their content
Various 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?
Have the UI agent subscribe to the Link extraction agent for links that are relevant to its user’s interests
Store the links under a given context using the interest representations
The Scenario
Proxy Component
The UI Agent
Agent InteractionComponent
UI Agent Presentationcomponent
Personal Profileand links
monitorandinform
search,browse,
bookmark
The Web
Fetch Webpages
Consult and Update
modifiedPages
httprequests
Agent InteractionComponent
Downloading andLink creation component
Link context determinationand storage base
Context linkbaselinks
urls, linkrequests in
context
QuIC Search Engine
User interface agent builds a user profile by monitoring bookmarking, browsing and searching activities
Profile determines contexts of user’s interests which are used subscription to links in ‘context’
Links are cached in personal linkbases and rendered based on document context
The Evaluation experiment
Goal: to study the implications of dynamically creating and adding links in their proper contexts on the process of locating information
The Experiment
In the first phase 2 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
In the second phase the 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
In the context of Vannevar Bush:Memex, Vannevar Bush, Vannevar, Bush, MIT, timeline, As We
May Think, Profile Tracer, Differential Analyzer, 1945
In the context of George W. Bush:George, Bush, President, Laura Welch Bush, Laura, Welch,
Governor Bush, Texas, photo gallery, Presidency, News
In the context of CORBA:Distributed Applications, CORBA, OMG, ORB, Distributed Objects,
Objects, IDL Interfaces, IDL, Object References, CORBA Architecture
Evaluation Results
On 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
Links 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
Allowing users to control the contents of their own linkbases
Getting user feedback on recommended documents
Investigating the use of natural language techniques in link phrase extraction
Experimenting with ways of achieving a more localized level of contextualization
QuestionQuestionss