Docstoc

Adaptive Hypermedia

Document Sample
Adaptive Hypermedia Powered By Docstoc
					    12
Authoring of Adaptive (and Adaptable)
    Educational Hypermedia
                        A3EH Course ; day1
                        Dr. Alexandra Cristea
                             a.i.cristea@tue.nl

                      http://wwwis.win.tue.nl/~alex/

Department of Computer Science        Mekrijrävi International Summer School 25-30.9.05
    12
     Overall Plan
     • Site
         – http://www.win.tue.nl/~acristea/A3EH/
     • Theory
         – at lectures
     • Practical tasks
         – in groups (one result per group)
         – tasks will be given at lectures and explained again in detail before
           starting the actual group work
         – discussions
     • Presentations
         – In groups (one presentation per group)
         – Interim and final
         – Practical task result presentation


Department of Computer Science          Mekrijrävi International Summer School 25-30.9.05
    12
     Outline Theory
     1. Adaptive Hypermedia of the Past, Present
        and Future
     2. Example systems and applications
     3. Authoring for Adaptive Hypermedia
     4. AH Authoring reference architecture: LAOS
     5. A closer look on adaptation design: LAG
     6. Learning Styles in Adaptive Hypermedia
     7. Conclusions

Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
  12 tasks
Outline practical
•        You will mainly work with 3 online systems:
1.       Authoring system: MOT for creation of adaptive courses
     –     http://wwwis.win.tue.nl/MOT03/TeachersSite-html/Yes.html
2.       Delivery System: AHA! for visualization of adaptive courses
     –     http://wwwis:8090/ahamot/
3.       Conversion system MOT2AHA for converting between the
         two
     –     Last 3 links at: http://wwwis:8090/ahamot/author/
•        optionally with 3 proceedings of the A3EH workshop
         series:
     –     A3EH 1: http://wwwis.win.tue.nl/~acristea/WBE/
     –     A3EH 2: http://wwwis.win.tue.nl/~acristea/AH04/papers/AAAEH-
           proceedings_1-11newest.pdf
     –     A3EH 3: http://wwwis.win.tue.nl/~acristea/AAAEH05/AIED2005.htm
Department of Computer Science              Mekrijrävi International Summer School 25-30.9.05
    12
     Outline Theory
     1. Adaptive Hypermedia of the Past, Present
        and Future
     2. Example systems and applications
     3. Authoring for Adaptive Hypermedia
     4. AH Authoring reference architecture: LAOS
     5. A closer look on adaptation design: LAG
     6. Learning Styles in Adaptive Hypermedia
     7. Conclusions

Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
    12
1. Adaptive Hypermedia of Past, Present &
Future
    • Definitions
    • Why AH?
    • Application areas
    • What to adapt?
    • Adapt to what?
    • How to adapt - past?
    • Obstacles AH
    • New solutions
Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
    12
    1. Adaptive Hypermedia of the Past,
    Present and Future
     •   Definitions
     •   Why AH?
     •   Application areas
     •   What to adapt?
     •   Adapt to what?
     •   How to adapt - past?
     •   Obstacles AH
     •   New solutions

Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
    12




Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
    12
     Hypermedia

     • information supported by different
       media and structured according to the
       hypertext principle.
     • hypertext + multimedia




Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
    12
     Multimedia


          • more than one media can be used
              – e.g., video, sound and text, interactive
                application




Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
    12
     Hypertext
  • classical text - articulated info:
      – introduction, augmentation, conclusion.
  • Hypertext: allows access to different info
    in a non-linear way.
  • Hypertext = nodes + links.
      – nodes (pages): textual info
      – links: allow the user to activate other pages.


Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
    12
     Back to hypermedia
      • “ In Hypermedia every piece of information
        can be, at the same time, center and
        periphery, introduction and conclusion,
        important and unimportant according to the
        knowledge,    interests   and  navigational
        choices operated by the user.”
      • Hypermedia differs from hypertext in the
        nodes contents:
          – not only text data, but also multimedia data.


Department of Computer Science      Mekrijrävi International Summer School 25-30.9.05
    12
     What is Adaptive Hypermedia?
     • Hypermedia
         – different media types used in a single application (text,
           images, sound, video, …)
         – non-linear structure with navigation through hyper-links
     • Adaptive
         – application forms a model of the context in which it is used
           (user, place, time, device, etc.)
         – application adapts to that context (can show different
           information, different media, different links, etc.)
         – adaptation and user modeling interact with each other (or
           else we say the application is adaptable, not adaptive)




Department of Computer Science          Mekrijrävi International Summer School 25-30.9.05
    12
     Index
     •   Definitions
     •   Why AH?
     •   Application areas
     •   What to adapt?
     •   Adapt to what?
     •   How to adapt - past?
     •   Obstacles AH
     •   New solutions

Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
  12 personalization
 The need for




Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
    12
     Why AH?
             • Problems with hypermedia applications:
                 – information overload: no time or interest to
                   process all
                 – excessive navigational freedom: “lost in
                   hyperspace” which links are relevant (for this
                   user) ?
                 – comprehension: order (a.o.) may be relevant:
                   what has the user seen before when reaching a
                   certain node?
                 – presentation: what fits the user’s screen? how
                   much network bandwidth and processing power
                   is available?


Department of Computer Science     Mekrijrävi International Summer School 25-30.9.05
    12
     Why AH?
              • Opportunities with adaptive hypermedia:
                  – prune excess of information
                  – guide users towards relevant information
                    only (users can reach relevant information
                    more easily and more quickly)
                  – make sure users can understand the
                    presented information
                  – change the presentation so that it fits the
                    user‟s platform and environment


Department of Computer Science     Mekrijrävi International Summer School 25-30.9.05
    12
     Index
     •   Definitions
     •   Why AH?
     •   Application areas
     •   What to adapt?
     •   Adapt to what?
     •   How to adapt - past?
     •   Obstacles AH
     •   New solutions

Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
    12
     Application areas AH
     • Areas
         – Education
         – Commerce
     • Adaptation types
         – Adaptive Help
         – Adaptive Search
         – Expert systems – AI


Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
    12
    Application areas AH
     •   Educational hypermedia (course texts)
     •   On-line information systems
     •   On-line help systems
     •   Information retrieval hypermedia
     •   Institutional (or corporate) hypermedia
     •   Personalized views




Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
    12
     Application Areas
     • Educational hypermedia systems
         – on-line course text, with on-line multiple-choice or other
           machine-interpretable tests
     • On-line information systems
         – information “kiosk”, documentation systems, encyclopedias,
           etc.
     • On-line help systems
         – context-sensitive help, (think of “Clippy”)
     • Information retrieval and filtering
         – adaptive recommender systems
     • etc.



Department of Computer Science           Mekrijrävi International Summer School 25-30.9.05
    12
     Adaptive Educational Hypermedia
     • Origin: Intelligent Tutoring Systems
         – combination of reading material and tests
         – adaptive course sequencing, depending on test results
     • In Adaptive Educational Hypermedia:
         – more freedom for the learner: guidance instead of enforced
           sequence
         – adaptive content of the course material to solve
           comprehension problems when pages or chapters are read
           out of sequence
         – adaptation based on reading as well as tests




Department of Computer Science         Mekrijrävi International Summer School 25-30.9.05
    12 On-line Information
    Adaptive
     Systems
     • Examples: encyclopedia, documentation, but also
       shopping sites, airline reservation, etc.
         – goal: provide information about different topics
         – users are only interested in a few topics, not in studying the
           entire hyperspace
         – the system needs to know the user‟s goal(s) in order to
           adapt (goal can be a topic, a product, an airline trip…)
         – the system also needs to adapt to the user‟s knowledge and
           background, perhaps also location (e.g. departing city)
         – users need help most when the concepts they want do not
           match the concept structure of the application (e.g. they
           don‟t know a close airport to the destination of their trip)



Department of Computer Science          Mekrijrävi International Summer School 25-30.9.05
    12
     Adaptive On-line Help Systems
     • Like on-line information systems, but:
         – not independent but tied into an application (and called from
           that application)
         – (part of) the context is known through the application
         – often this context is the only information about the user
           needed to adapt the information
         – hyperspace is reasonably small
         – unfortunately adaptation does not turn bad help information
           into good, and it cannot compensate for missing help
           information
         – popular (bad) examples: Windows troubleshooter, Clippy




Department of Computer Science          Mekrijrävi International Summer School 25-30.9.05
    12
     Adaptive Information
     Retrieval/Filtering
     • Adaptive Retrieval:
         – adaptively refine search requests
         – adaptively filter out non-relevant search results
         – update user model based on implicit or explicit relevance
           feedback
         – context information to be used can be a task, perhaps from a
           workflow system
     • Adaptive Filtering:
         – filters “incoming” information without the user explicitly
           asking for it
         – a “personalized view” interface for the Web can also be
           viewed as a filter
         – relies on relevance feedback to form and update a user
           model

Department of Computer Science           Mekrijrävi International Summer School 25-30.9.05
    12
    Application areas AH
     •   Educational hypermedia (course texts)
     •   On-line information systems
     •   On-line help systems
     •   Information retrieval hypermedia
     •   Institutional (or corporate) hypermedia
     •   Personalized views

     • many (more) application areas
         – thus very different systems?

Department of Computer Science    Mekrijrävi International Summer School 25-30.9.05
    12
     Index
     •   Definitions
     •   Why AH?
     •   Application areas
     •   What to adapt?
     •   Adapt to what?
     •   How to adapt - past?
     •   Obstacles AH
     •   New solutions

Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
    12
     Traditional Hypermedia
                                 Document2
                                   Text
                                    …
                                  Pictures
             Document1
                                    …
                Text
                                   Link1
                …
              Pictures
                …
               Link1                                Document3
               Link2                                   Text
                                                       …
                                                     Pictures
                                                       …

Department of Computer Science     Mekrijrävi International Summer School 25-30.9.05
    12
     Adaptation on Trad. Hypermedia
                                 Document2
                                   Text
    Show text document 1            …
                                  Pictures
              Document1
                                    …
                Text
                                   Link1
                 …
               Pictures
                 …
                Link1                               Document3
                Link2                                  Text
                                                       …
                                                     Pictures
                                                       …

Department of Computer Science     Mekrijrävi International Summer School 25-30.9.05
    12
     Adaptation on Trad. Hypermedia
                                 Document2
                                   Text
  Don’t show text document 1        …
                                  Pictures
               Document1
                                    …
                 Text
                                   Link1
                  …
                Pictures
                  …
                 Link1                              Document3
                 Link2                                 Text
                                                       …
                                                     Pictures
                                                       …

Department of Computer Science     Mekrijrävi International Summer School 25-30.9.05
    12
     Adaptation on Trad. Hypermedia
                                 Document2
                                   Text
   Show link(s) document 1          …
                                  Pictures
              Document1
                                    …
                 Text
                                   Link1
                  …
                Pictures
                  …
                 Link1                              Document3
                 Link2                                 Text
                                                       …
                                                     Pictures
                                                       …

Department of Computer Science     Mekrijrävi International Summer School 25-30.9.05
     12
      Adaptation on Trad. Hypermedia
                                 Document2
                                   Text
 Don’t show link(s) document 1      …
                                  Pictures
               Document1
                                    …
                  Text
                                   Link1
                   …
                 Pictures
                   …
                  Link1                             Document3
                  Link2                                Text
                                                       …
                                                     Pictures
                                                       …

Department of Computer Science     Mekrijrävi International Summer School 25-30.9.05
  12 adapted? – classical views
What can be

     • Adaptive presentation:
         – change which information is shown
         – change how that information is shown
     • Adaptive navigation support:
         – change which links are shown
         – change how these links are shown
         – change the link destinations


Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
    12
     What Do We Adapt in AH?
     • Adaptive presentation:
         – adapting the information
         – adapting the presentation of that information
         – selecting the media and media-related factors such
           as image or video quality and size
     • Adaptive navigation:
         – adapting the link anchors that are shown
         – adapting the link destinations
         – giving “overviews” for navigation support and for
           orientation support
Department of Computer Science     Mekrijrävi International Summer School 25-30.9.05
    12                                 Adaptive Presentation




Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
                                 Adaptive Navigation
    12                           Support




Department of Computer Science      Mekrijrävi International Summer School 25-30.9.05
    12
     Adaptive presentation
     • The content of what is seen on the
       screen can be adapted according to
       current user‟s model status.
         – e.g., a qualified user can be provided with
           more detailed and deep info while a novice
           can receive additional explanation.




Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
    12
     Content adaptation types
     • Additional (or prerequisite or comparative)
       explanations: Under a given set of
       circumstances some additional content is
       presented.
     • Explanation variants: Different versions of an
       explanation exist and are selected depending
       on the user.
     • Sorting: The most relevant information for a
       user is presented first.

Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
    12
     Canned Text Adaptation
     • Inserting/removing fragments
         – prerequisite explanations: inserted when the user appears to
           need them
         – additional explanations: additional details or examples for
           some users
         – comparative explanations: only shown to users who can
           make the comparison
     • Altering fragments
         – Most useful for selecting among a number of alternatives
         – Can be done to choose explanations or examples, but also
           to choose a single term
     • Sorting fragments
         – Can be done to perform relevance ranking for instance



Department of Computer Science         Mekrijrävi International Summer School 25-30.9.05
    12
     Example from 2L690
     • Before reading about Xanadu the URL page shows:
         – …
           In Xanadu (a fully distributed hypertext system, developed
           by Ted Nelson at Brown University, from 1965 on) there was
           only one protocol, so that part could be missing.
           …
     • After reading about Xanadu this becomes:
         – …
           In Xanadu there was only one protocol, so that part could be
           missing.
           …




Department of Computer Science         Mekrijrävi International Summer School 25-30.9.05
    12
     Canned Text Adaptation (cont.)
     • Stretchtext
         – Similar to replacement links in the Guide hypertext system
         – Items can be open or closed; system decides adaptively
           which items to open when a page is accessed
     • Dimming fragments
         – Text not intended for this user is de-emphasized (grayed out,
           smaller font, etc.)
         – Can be combined with stretchtext to create de-emphasized
           text that conditionally appears, or only appears after some
           event (like clicking on a tooltip icon)




Department of Computer Science         Mekrijrävi International Summer School 25-30.9.05
    12                     The wrong example:
     ISIS Tutor with Link Annotation




Department of Computer Science       Mekrijrävi International Summer School 25-30.9.05
    12
     Adaptive navigation support
     • Guidance methods
         – Global guidance methods
         – Local guidance methods
     • Orientation support methods
         – Global orientation support
         – Local orientation support



Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
    12
     Link adaptation types
     • Direct guidance: Next button.
     • Restricting access
     • Removing, disabling, hiding.
     • Sorting and presenting the most
       relevant or most ready to be learned
       links first.
     • Annotation (colour)
     • Map adaptation techniques

Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
    12
     Adaptive Navigation Support
     • Direct guidance
         – like an adaptive guided tour
         – “next” button with adaptively determined link destination
     • Adaptive link generation
         – the system may discover new useful links between pages
           and add them
         – the system may use previous navigation or page similarity to
           add links
         – generating a list of links is typical in information retrieval and
           filtering systems




Department of Computer Science            Mekrijrävi International Summer School 25-30.9.05
    12
     Adaptive Navigation Support (cont.)
     • Adaptive link annotation
         – all links are visible, but an “annotation” indicates relevance
         – the link anchor may be changed (e.g. in color) or additional
           annotation symbols can be used
     • Adaptive link hiding
         – pure hiding means the link anchor is shown as normal text
           (the user cannot see there is a link)
         – link disabling means the link does not work; it may or may
           not still be shown as if it were a link
         – link removal means the link anchor is removed (and as a
           consequence the link cannot be used)
         – a combination is possible: hiding+disabling means the link
           anchor text is just plain text

Department of Computer Science           Mekrijrävi International Summer School 25-30.9.05
       12
       Example from Interbook
 4


  3


  2
                                                                       √




   1
     1. Concept role              3. Current section state
     2. Current concept state     4. Linked sections state


Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
    12
     Interbook: textbook window




Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
    12
     Adaptive Navigation Support (cont.)
     • Map adaptation
         – complete (site)maps are not feasible for a non-trivial
           hyperspace
         – a “local” or “global” map can be adapted by annotating or
           removing nodes or larger parts
         – a map can also be adapted by moving nodes around
         – maps can be graphical or textual
         – adaptation can be based on relevance, but also on group
           presence




Department of Computer Science         Mekrijrävi International Summer School 25-30.9.05
    12
     TV Scout: What‟s on Tonight?




Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
    12
     TV Scout: Forms and Graphical Interface




Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
    12
     What to adapt?




Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
    12
     Index
     •   Definitions
     •   Why AH?
     •   Application areas
     •   What to adapt?
     •   Adapt to what?
     •   How to adapt - past?
     •   Obstacles AH
     •   New solutions

Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
    12
        Adapt to what?

    •   User  user model (UM)
    •   Goals  goal model (GM)
    •   Domain  domain model (DM)
    •   Environment  presentation model (PM)




Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
    12
        Adapt to what?

    •   User  user model (UM)
    •   Goals  goal model (GM)
    •   Domain  domain model (DM)
    •   Environment  presentation model (PM)




Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
    12
     Adapt to what?



                                          Users
     Adapt to




Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
    12
         User modelling is always about guessing …




Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
    12
     User Model
     • The     user    model    is     the    system‟s
       representation of the user‟s state of mind.
     • The user model is actually a well-organized
       database, comprising information about the
       user.
     • This is constructed in such a manner as to
       guide the system‟s inference engine.
     • User model data are not static. They can be
       revised according to the current user‟s
       actions as they are monitored by the system.

Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
    12
  Classical User Model: Overlay UM

  • user‟s knowledge = subset of expert‟s
    knowledge
  • goal of tutoring: to enlarge this subset.
  • This model is particularly appropriate when
    the (teaching) material can be represented
    as a prerequisite hierarchy.


Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
    12




Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
    12
     Adapt to what (else)?
     • Knowledge about the subject domain
       (and possibly also knowledge about the
       system)
     • Preferences
     • Interests
     • Learning or cognitive styles
     • Background: profession, language,
       prospect, capabilities, experience, age
     • Navigation history
Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
  12
 Adapt to what?
 • Knowledge about the subject domain (possibly
   also knowledge about the system)
 • The user‟s knowledge is the basic driver behind
   the system‟s adaptation.
 • Different users have different knowledge status
   about a specific subject.
 • A single user can have variable knowledge status
   throughout his interaction with the system.
 • The system must be able to recognize the user‟s
   knowledge status, update his model and modify
   presentation and interaction accordingly.
Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
  12
Adapt to what?

     • Preferences
         – any explicitly entered aspect of the user
           that can be used for adaptation
         – Examples: media, character size, sound
           intensity, time frame, etc.




Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
  12
Adapt to what?
     • Interests
         – what is the user after?
             • fun or intensive study
         – what are the user‟s goals
             • immediate tasks versus what he wants to do with
               his life
         – what motivates the user?
             • good    grades      versus         career/          business
               opportunities
         – what could be rewarding or not in the
           presentation?
             • domain of illustrative examples
Department of Computer Science      Mekrijrävi International Summer School 25-30.9.05
 12
Adapt to what?

     • Learning or cognitive styles
         – to be treated in a following section




Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
   12what?
  Adapt to

     • Background & Experience:
         – background = user‟s experience outside the
           application
         – experience = user‟s experience with the
           application‟s hyperspace
         – profession, language(s), prospect, capabilities




Department of Computer Science     Mekrijrävi International Summer School 25-30.9.05
   12what?
  Adapt to

     • Navigation history
         – what has the user seen before coming
           here?




Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
    12
        Adapt to what?

    •   User  user model (UM)
    •   Goals  goal model (GM)
    •   Domain  domain model (DM)
    •   Environment  presentation model (PM)




Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
  12
Adapt to what?
• Goal
• (initial) purpose of the hypermedia
• answer to question
    – “Why should the user use the hypermedia system and
      what could the user actually achieve?”
• Goals can be local or global.
    – Local goals may changed quite often. For example, the
      problem-solving goal is a local one, which changes from
      one educational problem to another several times within a
      session.
    – Global goal can be the pedagogical goal.


Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
    12
        Adapt to what?

    •   User  user model (UM)
    •   Goals  goal model (GM)
    •   Domain  domain model (DM)
    •   Environment  presentation model (PM)




Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
    12
     Adapt to what?


                                  Domain model properties
     Adapt to




Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
    12
        Adapt to what?

    •   User  user model (UM)
    •   Goals  goal model (GM)
    •   Domain  domain model (DM)
    •   Environment  presentation model (PM)




Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
   12what?
  Adapt to

     • Context / environment
         – aspects of the user‟s environment, like
           browsing device, window size, network
           bandwidth, processing power, etc.




Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
    12
     Index
     •   Definitions
     •   Why AH?
     •   Application areas
     •   What to adapt?
     •   Adapt to what?
     •   How to adapt - past?
     •   Obstacles AH
     •   New solutions

Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
    12
     How do AH work?

Most AHS react to individual user requests:
1. retrieve the user model (a. o.)
2. (if necessary) retrieve the domain model
3. retrieve the requested resource(s)
4. perform adaptation to the resource
5. update the user model (a. o.)
(maybe 4 and 5 are reversed)

Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
    12
     Classic loop (Brusilovsky, „01)
  φιπθθθ




Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
    12
     Adaptive vs. adaptable

                                 personalized




                 adaptable                               adaptive
                                                       System-tuned
                User-tuned




Department of Computer Science       Mekrijrävi International Summer School 25-30.9.05
    12
     Adaptivity vs. adaptability
     • An adaptable system provides users
       with options (tuners / handles) of
       determining some alterations to aspect,
       contents or functionality of the system,
       according to their preferences.
     • An adaptive system adapts to the new
       conditions (usually deduced from a user
       model) automatically.


Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
    12




                                        Gerhard Fischer 1 HFA Lecture, OZCHI’2000

Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
    12
    A Comparison between Adaptive and Adaptable Systems




                                          Gerhard Fischer 1 HFA Lecture, OZCHI’2000

Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
    12
     AM: adaptation model

   • Purpose is to describe how an AHS:
       – updates the user model
       – generates adaptation (presentation specifications)
   • Description uses condition-action rules:
       – under which condition is the rule executed
       – which (user/ other model) concept attribute is updated
       – does this update trigger other rules?




Department of Computer Science    Mekrijrävi International Summer School 25-30.9.05
    12
     The Adaptation Engine
• The core of each AHS is an engine that
  executes the adaptation rules (or equivalent):
   – page access or user requests trigger one or more
     rules;
   – these rules generate user (a.o.) model updates;
   – the rules may trigger other rules that generate
     more updates; (does this process end ?)
   – the engine generates an adapted page.

Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
    12
     Web-based Adaptive Hypermedia
• Client-server architecture using HTTP
   – usually, page accesses are registered (less scrolling,
     within-page scripting code or animations, etc.)
   – following a link activates a server-side program (CGI-script,
     Java Servlet, …)
   – the program uses the link URL and the user model to
     determine which page to return
   – the program performs content and link adaptation based
     on the user model (and some adaptation rules)
   – the program updates the user model taking into account
     that the user will read the presented information
Department of Computer Science    Mekrijrävi International Summer School 25-30.9.05
    12
     Index
     •   Definitions
     •   Why AH?
     •   Application areas
     •   What to adapt?
     •   Adapt to what?
     •   How to adapt - past?
     •   Obstacles AH
     •   New solutions

Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
    12
 Is adaptive hypermedia possible?

                     • Yes: adaptive systems exist;
                       some people even claim they
                       work well.
                     • Maybe: (how) can adaptive
                       systems find out what users
                       want?
                     • Maybe not: can authors/
                       designers correctly interpret the
                       system‟s input to design
                       appropriate adaptation?
Department of Computer Science    Mekrijrävi International Summer School 25-30.9.05
    12
       Is adaptive hypermedia possible?

                   • Yes: adaptive systems exist; some
                     people even claim they work well.
                   • Maybe: (how) can adaptive systems
                     find out what users want?
                   • Maybe not: can authors/designers
                     correctly interpret the system‟s input
                     to design appropriate adaptation?
                                 We have to create help for authors!!


Department of Computer Science        Mekrijrävi International Summer School 25-30.9.05
    12
     Creation costs
     • We need to automatize authoring
         – Automatic authoring techniques
         – Open adaptive hypermedia
     • We need interchangeable, standardized
       AH objects
         – Adaptation patterns and standards
     • We need interchange protocols
     • We need benchmarks for evaluations

Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
    12
     Index
     •   Definitions
     •   Why AH?
     •   Application areas
     •   What to adapt?
     •   Adapt to what?
     •   How to adapt - past?
     •   Obstacles AH
     •   New solutions

Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
    12
     New, dynamic view of AH

                         text
                                                                      Bit contains
     Bits & pieces                                                  text, MM or link
                                 link


      Generation:
      -only text       text

                                 link
      -only link
                                             text
      -text & link                           link



Department of Computer Science          Mekrijrävi International Summer School 25-30.9.05
    12
     Dynamic AH
     • adaptive hypermedia can be also
       dynamic if presentation provided to the
       user is not a selection of predefined
       existent possible presentations, but is
       assembled “on-the-fly” from modular
       information items, and based on the
       automatic and constant monitoring of
       users‟ behavior.

Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
    12
     Open adaptive hypermedia
     • Open adaptive hypermedia systems are able
       to adapt to individual needs of the user of the
       hypermedia documents regardless of their
       origin.
     • Open hypermedia systems uses documents,
       which belong to an open repository of
       learning material.
         – e.g., course materials or a sequence of pages of a
           tutorial, or home page content.


Department of Computer Science    Mekrijrävi International Summer School 25-30.9.05
    12
     Solutions in short
     • Standardization
                                    New theoretical frameworks
     • Authoring                             needed!

                                       New implementations!




Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
     12
     Standardization
     • To be successfully implemented, AHS
        require guidelines that are shared and
        observed by organizations with a stake in the
        development and use of instructional
        technology materials. The ultimate form of
        these guidelines can be a reference model
        for developing high quality systems and
        contents.
     • Standardizing           means        construction                of
        definitions and specifications of semantics,
        syntax, rules, and framework descriptions. A
        standard must be neither prescriptive nor
        exclusive.
Department of Computer Science     Mekrijrävi International Summer School 25-30.9.05
    12 standardization work?
    How does
 • Standardization is about constructing a new
   language: Adaptation Modeling Language.
 • Rules for achieving standardisation reduce the
   difficulty in implementing runtime systems.
 • Adaptive hypermedia authors “are given higher
   level handlers of low level adaptation techniques”.
 • Reusability.
                – Reusable -Sharable Learning
       Objects - Adaptive Learning Strategies
 • Archiving.
 • Quality
Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
    12
     Current standards

  • Systems architecture
  • Runtime environment
  • Learning objects and Learning object
    metadata
  • Learners profile and performance information
  • Content sequencing and behaviour


Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
     12
      Main organizations
 • IEEE        LTSC      (Learning       Technology         Standards        Committee,
    http://ltsc.ieee.or)
 • European CEN/ISSS Learning Technologies Workshop,
    www.cenorm.be/isss/Workshop/lt/
 • The IMS (Instructional Management Systems, Global Learning
    Consortium Inc, www.imsproject.org)
 • The US ADLnet (Advanced Distributed Learning Network,
    www.adlnet.org)
  • CETIS (Centre for Educational Technology Interoperability Standards)
    http://www.cetis.ac.uk/
                 • AICC (Aviation Industry CBT Committee)
    http://www.aicc.org
 • ARIADNE (Alliance of Remote Instructional Authoring and Distribution
    Networks for Europe)http://ariadne.unil.ch/
 • Edutella Computer Science
Department of (http://edutella.jxta.org)    Mekrijrävi International Summer School 25-30.9.05
LOM
    12 (Learning Objects Metadata standard: current version 6.4)


  • The IEEE-LTSC (Learning Technology Standards
    Committee) LOM – became an official standard in June
    2002. LOM metadata schema is divided into 9 categories:
      –   general: title, language, keyword
      –   life cycle: author, publisher, version
      –   meta-metadata
      –   technical: format, size, etc.
      –   educational: interactivity type, etc.
      –   rights: price, copyright, etc.
      –   relation: between LOs
      –   classification: taxon, etc.
      –   annotation: date, etc.


Department of Computer Science              Mekrijrävi International Summer School 25-30.9.05
    12
     SCORM
     • A learning object is a reusable, media
       independent chunk of information used
       as a modular building block from e-
       learning content”




Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
    12
     Standardization: user profiling
     • not as advanced as work on Learning
       Objects.
     • However, the LTSC IEEE 1484.2 Learner
       Model WG Standard proposal for public and
       private information (PAPI) for learners is a
       multipart standard, defining several types of
       information:
         –   contact information (name, address),
         –   relation information (teammates, mentors),
         –   learner preferences,
         –   security information, etc.
Department of Computer Science      Mekrijrävi International Summer School 25-30.9.05
    12
     The Future… Ambient Intelligence
   • Intelligent home (and office or building)
       – automatic heating/climate control
       – automatic lighting, kitchen, …
       – automatic communication redirection
       – adaptive information services and help
       – adaptive technology makes the technology
         “disappear” into the environment
       – a dream? not for long!


Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
    12
Concluding
     Adaptive Hypermedia of Past, Present & Future
         –   Definitions
         –   Why AH?
         –   Application areas
         –   What to adapt?
         –   Adapt to what?
         –   How to adapt - past?
         –   Obstacles AH
         –   New solutions


Department of Computer Science      Mekrijrävi International Summer School 25-30.9.05
    12


                   Any questions?




Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05
    12
     Tasks afternoon

     • Task 1,2 from:
         – http://www.win.tue.nl/~acristea/A3EH/


     • For this you will need to have a short
       intro into MOT Essentials



Department of Computer Science   Mekrijrävi International Summer School 25-30.9.05

				
DOCUMENT INFO
Shared By:
Categories:
Tags:
Stats:
views:12
posted:8/14/2011
language:English
pages:103