Adaptive Hypermedia 2ID20 Course 7

1
Adaptive Hypermedia 2ID20Course 7

• Dr. Alexandra Cristea
• a.i.cristea_at_tue.nl
• http//wwwis.win.tue.nl/alex/

2
Outline

• Adaptive Hypermedia of the Past, Present and
  Future
• Example systems and applications
• AH Reference architectures AHAM - continuation
• Authoring for Adaptive Hypermedia
• AH Authoring reference architecture LAOS
• A closer look on adaptation design LAG
• Learning Styles in Adaptive Hypermedia
• Authoring system MOT
• Delivery System AHA!
• Conclusions

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Condition-Action Rules

• In many adaptation rules the event is tied to
  the condition
• pseudo CA rules, do not actually need the event
• In Condition-Action rules a change to the
  condition is the triggering event
• a CA rule becomes active when its condition
  becomes true. (rule is activated)
• a CA rule becomes inactive when its condition
  becomes false. (rule is deactivated)
• when a CA rule (action) is executed all the
  conditions are checked. Rules whose condition
  becomes true (and was false) are queued for
  execution
• when a CA rule is executed the rule only
  activates itself if its condition remain true and
  some attribute value in that condition has changed

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Condition-Action Rules (cont.)

• General execution model
• compute the initial set of active rules and place
  them in a collection (set, queue, stack)
• repeat until there are no more rules in the
  collection
• select a rule r
• if rs condition is true
• then execute rs action
• and add newly activated rules to the collection
• Note an activated rule may become inactive
  before it is executed

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Static Analysis of CA Rules

• The activation graph contains a node for each CA
  rule (instance) r. It contains an edge ri ? rj
  iff the action of ri updates a concept/attribute
  used in the condition of rj
• The activation graph only represents changes to
  the condition. It may not be an activation and it
  may even be a deactivation
• Theorem If there are no cycles in the activation
  graph then the rule execution is guaranteed to
  terminate
• This is a conservative way to guarantee
  termination
• Improvement look at what the action does, and at
  the condition
• More improvement look at rule sequences from
  initial state

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Static Analysis of CA Rules (cont.)

• Lemma two distinct rules ri and rj commute if
• ri cannot activate rj
• ri cannot deactivate rj
• conditions 1 and 2 with i and j reversed
• ris action and rjs action commute
• Theorem a rule set R is confluent if all pairs
  of rules in R commute

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AHAM Rule Language

• We use AHAM to describe adaptive hypermedia
  systems
• AHAM ECA or CA rule language (we write the rules
  using a condition and action but the condition
  contains an event and the action can be quite
  complex with a condition of its own)
• SQL-like syntax
• used for generic or specific rules
• it is a description language, not an
  implementation language
• independent of the actual execution model
• We introduce the language through examples

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AHAM Rule Language (cont.)

• Example 1 decide when to show a fragment
• C select P.accessA update F.pres show
  where Fragment(P, F) and F.relevant true
• the where clause is shorthand for
• CR.cinfo.type Fragment and CR.ss1.uid
  P and CR.ss2.uid F and CR.cinfo.dir1
  FROM and CR.cinfo.dir2 TO and
  CR.ss.length 2 and CR.ss2.relevant true
• through P.access we monitor whether page P is
  accessed (it becomes true on access)

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AHAM Rule Language (cont.)

• Example 2 knowledge update
• C select P.access where P.ready trueA
  update P.knowledge well known
• We see here that there is a condition, separate
  from the event we only set the knowledge value
  to well known if the page is considered
  ready.

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AHAM Rule Language (cont.)

• Example 3 handling prerequisites
• C select C1.knowledge where C1.knowledge ?
  knownA update C2.ready true where
  Prerequisite(C1, C2) and not exists ( select
  C3 where Prerequisite(C3, C2)
  and C3.knowledge lt known )
• This rule expresses that a concept becomes
  ready when all its prerequisites are satisfied.
  This rule has an instance for each prerequisite
  of a concept

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Execution of AHAM CA rules

• The rule language does not specify the system
  behavior
• an execution semantics is still needed
• most systems use a queue for pending rule
  executions
• in most systems not all actions trigger or
  activate rules
• we must introduce execution phases in order to
  describe some systems behavior

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MOT to AHA! demos

• open http//localhost8080/aha/NeuralNetworksAll/
  for adaptation demo (beg-int-adv)
• non-adaptive version http//localhost8080/aha/Ne
  uralNetworksAlles/
• open MOT lesson Neural Networks II
• open strategy C\ALEXANDRA\MOT\mot2aha\mot2aha-v4
  .txt
• leave How Artificial Neural Networks came into
  being last for becoming int
• leave More details on the biological neural
  network last for becoming adv
• open http//localhost8080/aha/NeuralNetworksRemov
  eExtraInfo/registration.html for demo beg-int-adv
  with removal of already seen items
• http//localhost8080/ahanew/ for frame demo (old
  directory)

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Deadlines more info

• Assignment (N. Stash) 9-02-2005
• should be done in groups (except for learning
  style evaluation usage)
• questionnaire is individual!
• 1 installation per group
• Project 16-03-2005
• you can get more videos for your MultiMedia, cut
  at powerpoint page size on AH course homepage

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Outline

• Adaptive Hypermedia of the Past, Present and
  Future
• Example systems and applications
• AH Reference architectures AHAM
• Authoring for Adaptive Hypermedia
• AH Authoring reference architecture LAOS
• A closer look on adaptation design LAG
• Learning Styles in Adaptive Hypermedia
• Authoring system MOT
• Delivery System AHA!
• Conclusions

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Bugs known problems for AHA!

• Also available at http//wwwis.win.tue.nl/nstach
  /assignment/assignment.html
• Some problems are already known and treated last
  year, at the AH forum http//wwwis.win.tue.nl/w-a
  gora/index.php?bncheetah_2id20
• In Tomcat administration tool, when creating AHA!
  context The Path refers to the start of the
  local URLs that refer to AHA!. This path is used
  in for instance the login forms for applications.
  If you choose /aha everything will work out of
  the box but if you choose another name you have
  to also change the references to /aha in the
  login forms, registration and other pages all
  files in xhtml directory, header.xml, index.html,
  Registration.html
• You can use the following file to make the
  changes of the path for more files at once
  follow the instructions in the Perl file
  http//wwwis.win.tue.nl/acristea/AH/CoursePowerpo
  intsDemos/good-aha.pl
• If you made this changes, you need to reload the
  page for the changes to be visible (index or
  Registration page)
• If you install AHA! and immediately try to go to
  any application you won't see anything, because
  the application first needs to be converted into
  internal AHA! format using the GraphAuthor
  (option "Save/SaveToAHA").

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Bugs known problems for AHA!

• access the author information through the AHA!
  configurator at http//localhost8080/aha/Config
  and NOT through the AuthorWorkplace, otherwise
  you will get a Java error
• In a posting at 15-03-2004 Paul de Bra replies
  Sorry about that. This is because of an upcoming
  new tool, called "testeditor" which is already
  asked for but not present. Please add the
  following line to the aha/WEB-INF/ahaconfig.xml.in
  file (or after installation to
  aha/WEB-INF/ahaconfig.xml as well) ltVariable
  id"testeditorpath"gt/author/TestEditor/lt/Variablegt
  You can add this for instance after the line
  with the formeditorpath.

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Bugs known problems for AHA!

• Registration page for "AHAtutorialLS" contains a
  Javascript which is not browser-independent it
  doesnt work with Internet Explorer, but it works
  with Firefox 1.0 from http//www.mozilla.com
• This Javascript sets the values for some "hidden"
  parameters from the registration form. (The user
  is not asked to specify their values manually.)
  To check if this is a problem, open the file
  corresponding to a newly created profile. This is
  the last created file in "xmlroot/profile"
  folder, with the largest "id" as its name. Look
  into this file for the line "ltkeygtpersonal.initial
  VERBvsIMlt/keygt". If the value for
  "personal.initialVERBvsIM" attribute is empty -
  indicated by the following line "ltvaluegtltvaluegt"
  (and not ltvaluegt50lt/valuegt, for example) this
  means that the Javascript is not executed.
  Therefore your browser does not support it.

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Bugs known problems for AHA!

• While experimenting with different strategies
  always leave "VerbalizerVersusImager" applied.
  Otherwise some information on the pages might be
  missing.
• To check how the application of different
  strategies results in the presentation for the
  user create new anonymous session each time after
  you work with the Graph Author.
• Do not forget to remove the "temp" folder from
  the application directory when you make some
  changes to the concept structure of the
  application, for example, apply strategies in the
  "GraphAuthor", before starting working with the
  updated application .

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Bugs known problems when using two AHA! versions

• You are using two AHA! versions for your
  assignment, respectively project
• The AHA! with learning styles and
• The AHA! for MOT to AHA! converter
• You have two choices
• Either to make 2 AHA! contexts in Tomcat
  administration tool (e.g., you saved your two
  AHA!s in C/ahals/ and C/ahamot, so you will
  have a context with document bases as above and
  paths /ahals and /aha). This will mean that you
  need to change the contents of files as explained
  before.
• The other version (if you already installed AHA!
  with learning styles with path /aha instead of
  /ahals) is to use AHA! with learning styles
  first, and then rename the C/ahamot directory to
  C/ahals to be able to function with the
  previously defined context, without making any
  other modifications of file contents.
• This should work as you will not be using the
  Graphauthor in mot2aha conversion anymore.

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Bugs known problems for MOT

• Some also available at
• http//e-learning.dsp.pub.ro/mot/
• in lesson/ Conceptmaps
• MOT user guide
• MOT generalities installation
• http//wwwis.win.tue.nl/acristea/HTML/USI/MOT/hel
  p/

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Bugs known problems for MOT

• Mot2caf seems to be working ok, but caf2aha gives
  me a java error parsing my (CAF) xml-document...
• the CAFtoAHA.bat batch file has been added 2
  library paths, and the CAF.dtd file has been
  slightly modified in the zip file Please use
  these modified files!
• (at http//wwwis.win.tue.nl/acristea/HTML/USI/MO
  T/MOT2AHA!/aha3.0-pre18.zip)

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Bugs known problems for MOT

• If you use html or other tags with MOT, then the
  lesson view might behave irregularly (because the
  teacher view truncates the text).
• The solution is NOT to have html tags in the
  first 30 characters of the text (or to close them
  within the first 30 chars).

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More about Learning Styles in MOT

• How to simulate a Textual versus Imager in MOT?
• How to simulate a Globalizer versus Sequentialist
  in MOT?