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Foundations of Adaptive Hypermedia
Foundations of Adaptive Hypermedia
Heiko Spallek, DMD, PhDCenter for Dental Informatics
University of Pittsburgh, School of Dental Medicine, Pittsburgh, PA
March 30, 2005
Dental Informatics Seminar (2202)
Foundations of Adaptive Hypermedia
Foundations of Adaptive Hypermedia
Agenda Background
e-learning hype reality check current status of dental online courses
Adaptive Hypermedia definitions, concepts usage in education, information retrieval, kiosk & help systems
Conceptual architecture Technical implementation In-class assignment Evaluation Conclusions
Foundations of Adaptive Hypermedia
Hype About E-learning
General number of online courses 50,000 100,000 between 1998 and 1999 * online learning market: $2.2 billion in 2001, estimated: $11.4 billion by 2003 * e-learning conference in Europe attracted 10,000 attendees last year
Dentistry 1998: 158 online continuing dental education (CDE) courses from 32 providers 2001: just DentalxChange.com: 428 courses in 27 different categories
* International Data Corp.
Foundations of Adaptive Hypermedia
Reality check“E-learning is the revenge of the nerds.”
evaluation of 158 online continuing dental education uncovered major deficiencies in existing Web-based CDE courses *
no author indicated relation between course length and credit hours varies
market for course shells immature no standards → risk of losing content no peer-review process for online learning resources → no academic credit usually no formative or summative evaluation high drop-out rate (based on meta analysis of multiple studies) in dentistry/medicine: no one has reported profits yet (break even for online course: 300-500 participants)
* Schleyer T, Pham T. Online continuing dental education. Journal of the American Dental Association 1999;130(June):848-854,877-878
Foundations of Adaptive Hypermedia
Current state-of-the-art dental online course collection of static Web pages
translations of existing lecture notes existing course manuals existing papers
= first generation online course model
Course material is still implicitly oriented for a traditional on-campus audience!
Foundations of Adaptive Hypermedia
Generations of online courses
1. Generation static pages
2. Generation adapted by the instructor to different audiences (static versions of the same course saved at different locations)
3. Generation adaptive to the individual learner
Foundations of Adaptive Hypermedia
Adaptive Hypermedia (AH)
- new direction of research - crossroads of hypermedia and user modeling- model of the goals, preferences, knowledge of each individual user- use of model throughout interaction with user- adapt to the needs of user
Brusilovsky 1996, Brusilovsky 2001
Foundations of Adaptive Hypermedia
Definition User Model- “mental state” of the user *- AH system keeps a model of the user - to adapt teaching sequence, presentation - for each Knowledge Item (KI)
- individual user model
- stores some value
- estimation of the user’s knowledge level of this concept **
* De Bra and Calvi 1998
** Brusilovsky 1996
Foundations of Adaptive Hypermedia
AH ― Areas of Application
• educational hypermedia• online information systems• online help systems• information retrieval hypermedia• institutional hypermedia• systems for managing personalized views in information spaces
Brusilovsky, P. (2001) Adaptive hypermedia. User Modeling and User Adapted Interaction, Ten Year Anniversary Issue (Alfred
Kobsa, ed.) 11 (1/2), 87-110
Foundations of Adaptive Hypermedia
Adaptivehypermediatechnologies
Adaptivepresentation
Adaptivenavigation support
AdaptiveMultimedia
presentation
Adaptive textpresentation
Adaptationof modality
Canned textadaptation
Naturallanguage adaptation
Inserting/Removingfragments
Alteringfragments
Sortingfragments
Dimmingfragments
Strechtext
Direct guidance
Adaptive linksorting
Adaptive linkhiding
Adaptive linkgeneration
Map annotation
hiding
disabling
removal
The updated taxonomy of adaptive hypermedia technologies; Brusilovsky, P. (2001) Adaptive hypermedia. User Modeling and User Adapted Interaction, Ten Year Anniversary Issue (Alfred Kobsa, ed.) 11 (1/2), 87-110
Taxonomy of AH Technologies
Foundations of Adaptive Hypermedia
Curriculum Sequencing
active - implies a learning goal- best individual path to achieve the goal
passive- reactive technology- offers the user a subset of available learning material fill the gap in student's knowledge
Foundations of Adaptive Hypermedia
AH Technologies in Web-based Educationadaptive navigation support technology
- changing the appearance of visible links
= generalization of curriculum sequencing technology in a hypermedia context
- direct guidance, adaptive link annotation, adaptive link hiding
adaptive presentation technology
- adapt the content of a Web page to the user's goals, knowledge and other information stored in the user model
- pages are adaptively generated or assembled from pieces for each user
Foundations of Adaptive Hypermedia
Conceptual architecture
1. What features of the learner can be used as a source of the adaptation?
2. What can be adapted in a technical feasible manner?
Foundations of Adaptive Hypermedia
1. What features of the learner can be used as a source of the adaptation?
user’s knowledge- pre-test results- completion of quizzes throughout the course
user’s interests/goals- selection of a specific learning goal
user’s traits- learning style
Foundations of Adaptive Hypermedia
2. What can be adapted in a technical feasible manner?
user’s learning goal compilation of KIs
individual curriculum (active sequencing)
system’s estimation of the learner’s knowledge level of each KI stored modifies content (adaptive presentation)
Foundations of Adaptive Hypermedia
Adaptiveness
adaptive text presentation- inserting/removing of fragments- altering fragments- stretch text
adaptive navigation support - adaptive links: hiding- adaptive link annotation- sitemap adaptation
admission to final quiz only after mastering of all offered KIsforced repetition of KI example-based learning versus concept-based learning
Foundations of Adaptive Hypermedia
AH system stores information
User ModelUser Info Course Info
Learning Goal Knowledge Items
A G B D E H O J L T
User
provides enrollment information
Demographic Information
Demographic
Access
Privacy
AccessRightsPrivacyInformationLearningGoal
performes pre-test
A
Estimation of user’s knowledge
Knowledge Assessment
GB
DE H
OJ
L
T
Learning style
Final test
Test history
provides traits
LearningStyle AH system
compiles KIsAH system
compiles pre-testEstimation of
user’s knowledgeAH system adjusts KIs
used for adaptation effect
AH system compiles curriculum
AH system adjusts user model
Test results are used for revising the user model.
O
Eligibility for Final Test
A G B E HJ
T
Final test
AH system compiles finalAH system
evaluates final
Test results
Foundations of Adaptive Hypermedia
Technical Implementation
Learner Environment
Authoring Tool
Foundations of Adaptive Hypermedia
Authoring Tools general course setting views of KIs
- abbreviated version of the core explanation (short)- for novice users (basic)- very detailed high-level textual explanation (main)- for graduate level knowledge (advanced)
multiple-choice questions fill-in-the-blank questions descriptive / online examples prerequisites KI metadata: keywords, semantic
Teaching Tools
student registration, performance, question analysis
Foundations of Adaptive Hypermedia
Learner Environment
General design approach follows Mark Weiser’s idea:
“The most profound technologies are those that disappear. They weave themselves into the fabric of everyday life until they are indistinguishable from it.”
Scientific American, 265(3):94--104, September 1991
Foundations of Adaptive Hypermedia
Learner Environment
Overview page- background about the subject of the course- explanation about the concept of AH- introduction to personal tutor - acknowledgements
Foundations of Adaptive Hypermedia
Learner Environment
Emotional Intelligence?
show emotional behavior (e.g. the persona-effect, help relieve frustration, recover to a positive emotional state)
beneficial for tutoring agents and learning software C Elliot, J.C. Lester, J. Rickel. Integrating affective computing into animated tutoring agents
In Proceedings of the IJCAI Workshop on Animated Interface Agents
Nagoya, Japan, 1997, 113–121
improve user acceptanceJ. Klein. Computer Response to User Frustration. TR480, MIT, 1998
Foundations of Adaptive Hypermedia
Learner Environment
- user model is dynamic and is continuously revised- not based on the content reviewed
Beaumont 1994
Boyle and Encarnacion 1994
Vassileva 1996
Henze et al. 2002
Foundations of Adaptive Hypermedia
User ModelUser Info Course Info
Learning Goal Recompile Knowledge Items
A U F
User
Demographic
Access
Privacy
LearningGoal
A
Estimation of user’s knowledge
GB
D
OJ
Learning style
Test history
AH system re-compiles curriculum
User changes learning goal.
K RE
L
STM
H
New curriculum
Foundations of Adaptive Hypermedia
Annotations
- feedback is encouraged - annotations = informal continuous formative evaluation *
all KIs are annotatable by learners
* Henze et al. 2002
Foundations of Adaptive Hypermedia
Design
- cross platform, all browsers- screen resolutions with a minimum of 800x600 pixel- Guidelines of the Design of Educational Software *
* ANSI Standards Committee on Dental Informatics
Foundations of Adaptive Hypermedia
Technology
Purpose Technology
Web server for hosting IIS on MS-Windows 2000 Server
Programming language Scripting language: PHP version 4 and Perl-compatible regular expression
Database (highly granular storage) MySQL version 3.23.47 on Linux
Validation of user input JavaScript
Authentication Cookies
Foundations of Adaptive Hypermedia
Users AnnoUsers
AnnoKI
Descriptive Examples
Prerequisites
KIQuestions
KIDescript
Ex
QuestionsLog
KIAnnotation
User Model
Questions
Foundations of Adaptive Hypermedia
PHP Scripting// check what is up with prerequisites
if($prereq!="disregard"){
$queryPrereq = "select Requires from AH_Prerequisites where KI='$KIID'";
$dbPrereq->query($queryPrereq);
if($dbPrereq->num_rows()){
$querygetKI = "select AH_Knowledge_Items.KI_title, AH_Knowledge_Items.KIID from AH_Prerequisites, AH_Knowledge_Items where AH_Prerequisites.KI='$KIID' and AH_Prerequisites.Requires=AH_Knowledge_Items.KIID";
$dbgetKI->query($querygetKI);
$KItitlewithlink="";
while($dbgetKI->next_record()):
$vKI_title = $dbgetKI->Record["KI_title"];
$vKIID = $dbgetKI->Record["KIID"];
$score=getscore($vKIID, $UserID);
Foundations of Adaptive Hypermedia
Evaluation
1. initial review (cognitive walkthroughs )
2. alpha-test (task-oriented)
3. formative evaluation (heuristic evaluation & end-user testing)
4. summative evaluation (end-user testing) [planned]
Foundations of Adaptive Hypermedia
Cognitive Walkthroughs
Goal: solve anticipated problems before bringing the course to users for testing
- performed independent and under observation of the developer
Results (encountered problems were fixed immediately )- confusing labels of fields- confusing options during enrollment- missing guidance on start page- repetition of test questions- inadequate feedback for wrong answers
Foundations of Adaptive Hypermedia
Alpha Test
task-oriented alpha test- complete the course - determine deficiencies (educational, instructional design, technical,
design and layout)- send an unstructured informal feedback
Results (encountered problems were fixed immediately )- general feedback was positive- personal tutor concept was beneficial- 12 specific usability, functionality issues were discovered (regarding: change
of setting, annotations, quiz, flow, sequencing)
Foundations of Adaptive Hypermedia
Formative Evaluation I
Usability Inspection: Heuristic Evaluation
- general heuristic for UI design (Jakob Nielsen)- heuristic extracted from ANSI standard “Guidelines for the Design of
Education Software”http://di.dental.pitt.edu/edswstd/
Foundations of Adaptive Hypermedia
In-Class Assignment
Evaluate the pre- and post-questionnaires− Problems/Critique− Order of questions− Comparing terms− Formatting− Disclaimer
Foundations of Adaptive Hypermedia
Formative Evaluation II
End-user testing− separation between delivery (media) and instructional method
− use of a validated instrument
Evaluation of– participants’ reactions
– achievement of program objectives
• changes in student learning
• values
• motivations
• ability to transfer knowledge acquired outside the instructional setting
Foundations of Adaptive Hypermedia
Conclusions
• applying of established principles of AH research• state-of-the-art programming environment• separation of content and design• Web-based delivery system For the first time, a dental educational delivery system adapts itself
dynamically using active and passive curriculum sequencing and adaptive presentation.
authoring process = challenge ** Brusilovsky, Eklund, and Schwartz 2002
* De Bra and Calvi 1998