University of Malta CSA4080: Topic 7 © 2004- Chris Staff 1 of 15 CSA4080: Adaptive Hypertext...
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1 of 15 [email protected] University of Malta CSA4080: Topic 7 © 2004- Chris Staff CSA4080: Adaptive Hypertext Systems II Dr. Christopher Staff Department of Computer Science & AI University of Malta Topic 7: Adaptation Techniques
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University of Malta CSA4080: Topic 7 © Chris Staff 3 of 15 Stages in the Adaptation Process Collect data about the user Process data to build/update user model Apply user model to provide the adaptation –Last stage always fully automated in adaptive hypertext systems –1st and 2nd stages may require user intervention. Ideally, fully automated
Transcript of University of Malta CSA4080: Topic 7 © 2004- Chris Staff 1 of 15 CSA4080: Adaptive Hypertext...
1 of [email protected] University of MaltaCSA4080: Topic 7
© 2004- Chris Staff
CSA4080:Adaptive Hypertext Systems II
Dr. Christopher StaffDepartment of Computer Science & AI
University of Malta
Topic 7: Adaptation Techniques
2 of [email protected] University of MaltaCSA4080: Topic 7
© 2004- Chris Staff
Aims and Objectives
• Review of stages in the adaptation process and adaptation techniques from CSA3080
• Adaptive navigation in Letizia, WebWatcher, and HyperContext
3 of [email protected] University of MaltaCSA4080: Topic 7
© 2004- Chris Staff
Stages in the Adaptation Process
• Collect data about the user• Process data to build/update user model• Apply user model to provide the adaptation
– Last stage always fully automated in adaptive hypertext systems
– 1st and 2nd stages may require user intervention. Ideally, fully automated
4 of [email protected] University of MaltaCSA4080: Topic 7
© 2004- Chris Staff
Stages in the adaptation process
• If user and system need to co-operate to achieve adaptivity, then it is called collaborative user modelling
Application"Administrator"
UserSystem
Data about user
User Model
Adaptation Effect
Processes
ProcessesCollects
Provides
Edits
Provides
Edits
Provides
From [Brusilovsky96]
5 of [email protected] University of MaltaCSA4080: Topic 7
© 2004- Chris Staff
Problems Revisited
• Lost in HyperSpace• Cognitive overload• Complexity of the search space• Search-browsing• Static hypertext structure
6 of [email protected] University of MaltaCSA4080: Topic 7
© 2004- Chris Staff
Generic solutions
• Adaptive Presentation• Adaptive Navigation
7 of [email protected] University of MaltaCSA4080: Topic 7
© 2004- Chris Staff
What can be adapted?
• A hypertext is a collection of nodes that are connected by links
• So what can be adapted?– The node content and user interface - adaptive
presentation– The node organisation and hyperspace
representations (e.g., index, map, overview) - adaptive navigation
8 of [email protected] University of MaltaCSA4080: Topic 7
© 2004- Chris Staff
Adaptation Technologies
9 of [email protected] University of MaltaCSA4080: Topic 7
© 2004- Chris Staff
Adaptive Navigation
• Adaptive Navigation-local reconnaissance is highly related to link annotation
• E.g., Letizia, WebWatcher, Personal WebWatcher, HyperContext
• Already talked about Personal WebWatcher in Topic 4 (User Modelling) and CSA3080
10 of [email protected] University of MaltaCSA4080: Topic 7
© 2004- Chris Staff
Adaptive Navigation
• Differences in ITS and generic approaches to adaptive navigation– ITS aim is to transfer knowledge efficiently by
guiding through a learning space• Learned, ready to be learned, not ready to be learned
– Generic aim is to guide user through document space to relevant information (that is ideally also at the level of simplicity required by user!)
• Relevant, not relevant (what about “related to interest X?”)
11 of [email protected] University of MaltaCSA4080: Topic 7
© 2004- Chris Staff
Adaptive Navigation
• Letizia– Predicts a user’s interest as the user browses and
suggests links to relevant document in the vicinity of the user’s current location
– User tends to traverse Web graph “downwards”, but relevant information may lie sideways
– Observes user behaviour to determine user interests (eg, “skipping” links, bookmarking...)
– Makes recommendations based on “persistence of interest”
lieberman95letizia.pdf
12 of [email protected] University of MaltaCSA4080: Topic 7
© 2004- Chris Staff
Adaptive Navigation
• WebWatcher– Guides users through a web site based on
interaction with past users– Users express a query and are guided to
relevant documents– Associates what users are interested in with
documents that they mark as relevant– Marks up links with terms used by users, and
terms that occur in “downstream” documentswebwatcher.ijcai97.pdf
13 of [email protected] University of MaltaCSA4080: Topic 7
© 2004- Chris Staff
Adaptive Navigation
• HyperContext– Uses Information Retrieval-in-Context to guide
users to information in hyperspace (up to 7 link traversals away)
– Once user has navigated to a location which probably contains information, can submit query to search “context sphere”
– With Adaptive Information Discovery, system generates query on behalf of user
HCTCh5.pdf
14 of [email protected] University of MaltaCSA4080: Topic 7
© 2004- Chris Staff
Adaptive Presentation
• Already described MetaDoc’s Stretchtext functionality in CSA3080
• Approaches are generally intended to make the content more understandable to the user– automatically including glossary explanations
of terms unknown to the user– removing extraneous information, or
information known to the user– showing information in format preferred by
user...
15 of [email protected] University of MaltaCSA4080: Topic 7
© 2004- Chris Staff
Summary
• Reminded ourselves of the problems that AHSs try to fix
• The adaptation process• Adaptation technologies• Examples of systems that incorporate
adaptive navigation techniques
