The LAG Grammar for Authoring the Adaptive Web

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The LAG Grammar for Authoring the Adaptive Web

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

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Outline

• Introduction
• LAOS
• LAG
• Adaptation language
• Grammars
• GAL
• GIAL
• Adaptation procedures
• Adaptation strategies
• Conclusions

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LAOS

• based on AHAM
• supporting adaptive hypermedia authoring
• five layers
• Domain Model (DM)
• Goal and constraints Model (GM)
• User Model (UM)
• Adaptation Model (AM)
• Presentation Model (PM)

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LAG

• LAOS adaptation model
• direct adaptation techniques / rules
• IF-THEN, or condition-action (CA) rules
• adaptation language
• adaptation strategies adaptation procedures

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What does the adaptation language do?

• Captures adaptation patterns, typical for AHS,
  for reuse
• We start with a set of desired adaptive behavior
• While, For Break, Generalize, Specialize
• Conditions, Enough conditions
• Inherited from direct adaptation techniques If,
  Action

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Generalize, Specialize

• DM is concept map with hierarchy

Generalize
Specialize
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How to implement the adaptation language?

• context-free grammar
• tuple (V, T, S, P) with
• V a finite set of variables
• T a finite set of terminals
• S the start variable (S ? V)
• P a finite set of production rules of the form
  A ? x with A ? V and x ? (union(V, T)).
• GAL (written in
  CAPITALS, written bold, PROG, P).
• P given in Backus Naur Form

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GAL production rules
PROG ? STATEMENT STATEMENT ? IFSTAT WHILESTAT
FORSTAT BREAKSTAT GENSTAT SPECSTAT
(STATEMENT) STATEMENT ACTION
IFSTAT ? if CONDITION then
(STATEMENT) WHILESTAT ? while CONDITION do
(STATEMENT) TARGETLABEL FORSTAT ? for RANGE do
(STATEMENT) TARGETLABEL BREAKSTAT ? break
SOURCELABEL GENSTAT ? generalize((CONDITION)) SPE
CSTAT ? specialize((CONDITION)) ACTION ?
ATTRIBUTE OP VALUE
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GAL production rules cont.
CONDITION ? enough((PREREQ), VALUE)
PREREQ RANGE ? integer PREREQ ? ATTRIBUTE
COMPARE VALUE TARGETLABEL ? text SOURCELABEL ?
text_label_a ATTRIBUTE ? GENCONCEPT
SPECCONCEPT GENCONCEPT ?
CM_type.concept.attr CM_type.concept.attr_z
SPECCONCEPT ? CM_x.concept_y.attr_z OP ?
- . COMPARE ? lt gt
in VALUE ? text
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Break Labels

• while CONDITION do (
• while CONDITION do (
• if CONDITION then break sourcelabel
• ) label_y
• ) label_x

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Interface grammar

• GIAL (written in between brackets, written
  bold, Adaptive Strategy, P)

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GIAL production rules
Start ?Adaptive Strategy Adaptive
Procedure Adaptive Strategy ? add
statement Adaptive Procedure ? add statement
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Interface start
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GIAL production rules cont.

• add statement ? If While For
  Break Generalize Specialize Action
  adaptive procedure
• If ? add statement if condition then (add
  statement) add statement
• if condition then (add statement) add
  statement
• add statement if condition then
  (add statement)
• While ? add statement while condition do
  (add statement) label add statement
• while condition do (add statement)
  label add statement
• add statement while condition do (add
  statement) label
• For ? add statement for range do (add
  statement) label add statement
• for range do (add statement) label
  add statement
• add statement for range do (add
  statement) label

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If, While, For
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GIAL production rules cont.

• Break ? add statement break labeladd
  statement
• break label add statement
  
• add statement break label
• Action ? add statement attribute
  operator value add statement
• attribute operator value add
  statement
• add statement attribute
  operator value
• Generalize ?add statement generalize((conditi
  on)) add statement
  generalize((condition))add statement
• add statement generalize((condition))
• Specialize ? add statement
  specialize((condition)) add statement
  specialize((condition)) add statement
• add statement specialize((condition))

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Action, Generalize, Specialize
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GIAL production rules cont.

• condition ? prereq conditionprereqcond
  ition
• enough( condition,
  weight) condition
• enough( condition, weight)
  condition
• range ? integer
• prereq ? attribute compare value
• label ? text
• attribute ? generic specific
• generic?CM_type.concept.attrCM_type.concept.
  attr_z
• specific ? CM_x.concept_y.attr_z
• operator ? - .
• compare ? lt gt in
• value ? text

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Conditions enough conditions
number of conditions to fulfill
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MOT concept attribute
CREATE TABLE ConceptAttribute
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Verification

• Checking parse tree
• No variable types in MOT gt
• if attr_x lt 10 attr_y gt 5 then is illegal,
  because isnt a Boolean operator. However, we
  cannot determine if if attr_x lt 10 and attr_y gt
  5
• user-interface can enforce this partial check
• allows only Boolean operators between the
  attribute-conditions in a guard context

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Adaptive procedure (call)
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Adaptive Mini-strategies
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While If
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Generic vs. Specific attributes
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Conclusions

• design and implementation steps for adaptive
  language for AH creation
• exact definition of context free grammar
• creation steps of this grammar,
• creation of a grammar for actual system
  interface,
• frame-oriented, block-based GUI interface, only
  generating target language code.
• implementation authoring easier
• system allows the creation of adaptive strategies
  adaptive procedures AH adaptive patterns at
  various levels.

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Download trial

• Download
• http//adaptmot.sourceforge.net/
• Trial
• http//e-learning.dsp.pub.ro/mot/
• http//e-learning.dsp.pub.ro/motadapt/

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2nd International Workshop on Authoring of
Adaptive and Adaptable Educational Hypermedia

• Themes
• Design patterns for educational adaptive
  hypermedia
• Authoring patterns in adaptive/ adaptable
  educational hypermedia
• Authoring Tools for adaptive/ adaptable
  educational hypermedia
• Connecting adaptive educational hypermedia with
  cognitive/learning styles
• Collaborative issues for adaptive/ adaptable
  educational hypermedia
• Adaptation model transformations between adaptive
  educational hypermedia systems
• Evaluation of authoring tools for adaptive
  educational hypermedia
• Evaluation of adaptive educational hypermedia
  design patterns
• Evaluation of adaptive educational hypermedia
  authoring patterns
• http//wwwis.win.tue.nl/acristea/AH04/workshopAH.
  htm