samhaa r. el-beltagy, wendy hall, david de roure, and leslie carr intelligence, agents, multimedia...

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