Personalized Presentation in
Web-Based Information Systems
Michal Tvarožek, Michal Barla, Mária Bieliková
Institute of Informatics and Software Engineering
Faculty of Informatics and Information Technologies
Slovak University of Technology in Bratislava
Presentation outline
• Motivation
• What is the problem?
• Personalized presentation layer architecture
• Evaluation
• Summary
Sofsem 2007
22. 1. 2007
Tvarožek et al.
Personalized Presentation in Web-Based Information Systems
Motivation
• Large open information spaces
• Navigation and search related problems
– “Lost in hyperspace” syndrome
– Many (irrelevant) search results
 Adaptive WIS (web-based information systems)
– Few “standard” solutions
– New adaptive WIS = start from “square one”
Sofsem 2007
22. 1. 2007
Tvarožek et al.
Personalized Presentation in Web-Based Information Systems
Adaptive WIS problems
• No standard software architecture available
• Used mostly for e-learning applications
• Existing reference models (Dexter, AHAM)
– Deal with mostly abstract stuff
– Ignore software development and reuse aspects
• HERA methodology focuses more on presentation
than adaptation and user modeling
Sofsem 2007
22. 1. 2007
Tvarožek et al.
Personalized Presentation in Web-Based Information Systems
User modeling problems
• Automatic creation of a user model is difficult
• Logging without semantics
– Hard-coded evaluation logic depends on a specific domain and
implementation
• Web log analysis yields bad results
– Purely server-side approach
– Extensive pre-processing required
– Better suited for overall statistics gathering than the evaluation
of individual users’ characteristics
• Sharing of user models between tools or applications
requires common ground
Sofsem 2007
22. 1. 2007
Tvarožek et al.
Personalized Presentation in Web-Based Information Systems
Goals
• Devise the architecture of an adaptive WIS based
on the use of interconnected software tools
– Identify tool roles and interconnects
– Focus on extensibility and flexibility
– Support architecture/tool reuse for different
application domains
– Stress interoperability and “common ground” between
tools
Sofsem 2007
22. 1. 2007
Tvarožek et al.
Personalized Presentation in Web-Based Information Systems
Architecture overview
Personalized presentation layer
Server
Client
Input / Feedback
Presentation tools
Presentation
layer
Personalization
layer
Portal
Presentation
Presentation
Adaptation
Adaptation
HTML
fragments
Web
browser
Events
Events
User modeling
layer
User
characteristic
evaluation
Events
Server-side
logging
Events
Application logic layer
Data layer
Sofsem 2007
22. 1. 2007
Tvarožek et al.
Personalized Presentation in Web-Based Information Systems
Client-side
logging
Portal
• Facilitates user management tasks
– User registration
– User authentication and authorization
• Provides a single “global” user interface
– Ensures a common “look & feel”
– Integrates individual presentation tools as pluggable
portlets that can be added, removed or reordered
Sofsem 2007
22. 1. 2007
Tvarožek et al.
Personalized Presentation in Web-Based Information Systems
Architecture overview
Personalized presentation layer
Server
Client
Input / Feedback
Presentation tools
Presentation
layer
Personalization
layer
Portal
Presentation
Presentation
Adaptation
Adaptation
HTML
fragments
Web
browser
Events
Events
User modeling
layer
User
characteristic
evaluation
Events
Server-side
logging
Events
Application logic layer
Data layer
Sofsem 2007
22. 1. 2007
Tvarožek et al.
Personalized Presentation in Web-Based Information Systems
Client-side
logging
Presentation tools
• Perform adaptive presentation of content
• Allow for the use of different views/perspectives
suitable for individual users
– The same data can be viewed e.g. with a
• Faceted browser
• Cluster visualization tool
• Form-filling tool
Sofsem 2007
22. 1. 2007
Tvarožek et al.
Personalized Presentation in Web-Based Information Systems
Architecture overview
Personalized presentation layer
Server
Client
Input / Feedback
Presentation tools
Presentation
layer
Personalization
layer
Portal
Presentation
Presentation
Adaptation
Adaptation
HTML
fragments
Web
browser
Events
Events
User modeling
layer
User
characteristic
evaluation
Events
Server-side
logging
Events
Application logic layer
Data layer
Sofsem 2007
22. 1. 2007
Tvarožek et al.
Personalized Presentation in Web-Based Information Systems
Client-side
logging
Client-side logging
• Captures client-side events that would otherwise
go unnoticed
– Hovering on items
– Java script interaction
– “Back” button
– Form filling actions (e.g. the order of fields)
Sofsem 2007
22. 1. 2007
Tvarožek et al.
Personalized Presentation in Web-Based Information Systems
Architecture overview
Personalized presentation layer
Server
Client
Input / Feedback
Presentation tools
Presentation
layer
Personalization
layer
Portal
Presentation
Presentation
Adaptation
Adaptation
HTML
fragments
Web
browser
Events
Events
User modeling
layer
User
characteristic
evaluation
Events
Server-side
logging
Events
Application logic layer
Data layer
Sofsem 2007
22. 1. 2007
Tvarožek et al.
Personalized Presentation in Web-Based Information Systems
Client-side
logging
Server-side logging
• Integrates event data from various sources
• Creates one continuous stream of events for
– Each user
– Each user session
• Preserves the semantics of events supplied by individual
tools;
– Instead of GET www.x.com/overview.do?id=456&att=loc&r=33
– We get: <John>, <SelectRestriction>(<location>, <California>)
• Circumvents the tight coupling of presentation and log
analysis tools in traditional approaches
• Makes the log data accessible to all user modeling tools
Sofsem 2007
22. 1. 2007
Tvarožek et al.
Personalized Presentation in Web-Based Information Systems
Architecture overview
Personalized presentation layer
Server
Client
Input / Feedback
Presentation tools
Presentation
layer
Personalization
layer
Portal
Presentation
Presentation
Adaptation
Adaptation
HTML
fragments
Web
browser
Events
Events
User modeling
layer
User
characteristic
evaluation
Events
Server-side
logging
Events
Application logic layer
Data layer
Sofsem 2007
22. 1. 2007
Tvarožek et al.
Personalized Presentation in Web-Based Information Systems
Client-side
logging
User characteristics evaluation
• Continuously evaluates user event log data
– Estimates individual users’ characteristics
– Updates the user model
• Evaluates
– User navigation
– Implicit user feedback on presented content
– User behavior consistency or lack thereof
Sofsem 2007
22. 1. 2007
Tvarožek et al.
Personalized Presentation in Web-Based Information Systems
Evaluation
• Within the context of projects
– NAZOU (nazou.fiit.stuba.sk); domain: job offers
• Tools for Acquisition, Organization and Maintenance of
Knowledge in an Environment of Heterogeneous
Information Resources
– MAPEKUS (mapekus.fiit.stuba.sk); domain: scientific publications
• Modeling and Acquisition, Processing and Employing
Knowledge About User Activities in the Internet
Hyperspace
• Project constraints
– Implementation environment Java 5
– Presentation framework Apache Cocoon
– Ontological repository Sesame
Sofsem 2007
22. 1. 2007
Tvarožek et al.
Personalized Presentation in Web-Based Information Systems
How it works?
Corporate
Memory
Server
5. Domain model
User model
Domain
model
Prescott
4. Output
description
6. XHTML
fragment
2. Request
User
model
Factic
(other tools)
3. Domain model
User model
JOP/P3
1. Request
10. Response
7. Event
[Events]
8. User logs
Client
11. Response
SemanticLog
[Events]
User
logs
9. Notify
[Domain model]
[User model]
[User logs]
Sofsem 2007
22. 1. 2007
Web
browser
LogAnalyzer
[Call]
ConCom
Tvarožek et al.
Personalized Presentation in Web-Based Information Systems
Click
What can we do with it?
• Personalize facet layout
• Improve response time
• Reduce the number of necessary clicks
350
12
300
10
Click count
200
6
150
4
100
2
0
50
1 facet
2 facets
3 facets
11 facets
Clicks with recommendation
6
5
5
4
Clicks with adaptation
11
10
10
9
Clicks without adaptation
9
9
9
9
Time with recommendation
45
36
45
61
Time with adaptation
63
141
193
296
301
301
301
301
Time without adaptation
Number of active facets
Sofsem 2007
22. 1. 2007
Tvarožek et al.
Personalized Presentation in Web-Based Information Systems
0
Time [s]
250
8
Key issues I.
• Interoperability and “common ground” between tools
– Requires common information and semantics representation
 Ontologies provide means for defining common semantics
• Domain, user and event ontology
• Automatic user model acquisition
– Built-in comprehensive logging of user interaction with semantics
• Client-side
• Server-side
– Automatic event log evaluation
– Continuous user characteristics estimation
Sofsem 2007
22. 1. 2007
Tvarožek et al.
Personalized Presentation in Web-Based Information Systems
Key issues II.
• Flexibility and extensibility
– Modular architecture composed of interconnected
software tools
– Simultaneous support for the use and integration of
multiple presentation/user modeling tools
• Reusability
– Generic domain independent tools for specific tasks
Sofsem 2007
22. 1. 2007
Tvarožek et al.
Personalized Presentation in Web-Based Information Systems
Summary
• Generic architecture of the personalized
presentation layer of adaptive WIS
• Evaluation within projects
– NAZOU (nazou.fiit.stuba.sk) ~ job offers
– MAPEKUS (mapekus.fiit.stuba.sk) ~ publications
• Future work
– Analyze possibilities of tool orchestration
– Devise methods of cooperation between multiple tools
used for the same task
Sofsem 2007
22. 1. 2007
Tvarožek et al.
Personalized Presentation in Web-Based Information Systems