Incorporating Cognitive/Learning Styles in a General-Purpose Adaptive Hypermedia System

Transcription

1 Incorporating Cognitive/Learning Styles in a General-Purpose Adaptive Hypermedia System Natalia Stash June 25,

2 Contents Introduction Goals of the Dissertation Implementation of a General-Purpose Adaptive Hypermedia System AHA! (Adaptive Hypermedia Architecture) Identification of Strategies Corresponding to Cognitive/ Learning Styles (CS/LS) Application and Visualization of CS/LS Strategies in AHA! Approach Validation and Evaluation Conclusions and Future Work 2

3 Subject of the Dissertation Adaptive Hypermedia Computer Science topic Cognitive/Learning Styles Cognitive Psychology topic 3

4 What is Adaptive Hypermedia (AH)? Hypermedia non-sequential information, which is a combination of different media (such as text, images, audio) Classic example of hypermedia: World Wide Web (WWW) Problems with traditional hypermedia: navigation through a rich link structure the same information for everyone Adaptive Hypermedia & Adaptive Hypermedia Systems (AHS) allow to solve traditional hypermedia problems. They store user information in the user model and apply it for: adapting link structure and adapting content presentation 4

5 Application Areas of AHS Before AHA! (Adaptive Hypermedia Architecture) there were only special-purpose AHS used for creating e.g.: - online educational courses - virtual museums - online information kiosks - etc. However there were no general-purpose tools 5

6 What are Cognitive/Learning Styles (CS/LS)? Individual differences in perceiving and processing information, preferred ways of learning. Examples of CS/LS: imager vs. verbalizer global vs. sequential active vs. reflective 6

7 Why Applying Cognitive/Learning Styles? Learner s awareness of his/her style Matching teaching method (or instructional strategy) with CS/LS may increase learner s performance Deliberate mismatching can help develop new skills Letting learners try different instruction strategies 7

8 Goals of the Dissertation 1. Creating a General-Purpose AH Tool novelty: before AHA! there were only special-purpose tools 2. Providing Adaptation to Cognitive/Learning Styles bridge the gap between AH and CS/LS as a proof that a general-purpose tool has been created novelty: most AHS with support for CS/LS are bound to certain models CS/LS representation is predefined by the developers of the AHS rather than the developers of adaptive applications, pedagogues or psychologists 8

9 AHAM Model (Adaptive Hypermedia Application Model) Run-time Layer Presentation Specifications Adaptation Model Domain Model User Model Storage Layer Anchoring Within-Component Layer AHS = <Domain model, User model, Adaptation model, Adaptation Engine> 9

10 Design Requirements for a General-Purpose System adaptation types and techniques (overview of AHS) aspects used for adaptation (overview of AHS & AHAM) arbitrary concept relationships (overview of AHS & AHAM) generic adaptation rules (AHAM) handling non-monotonic user model updates and cycles in adaptation rules (AHAM) Design wishes Authoring tools (overview of AHS) Performance (overview of AHS) 10

11 AHA! : from version1.0 to version 3.0 AHA! engine Java servlets Pages from external WWW servers Authoring tools Concept Editor Graph Author Form Editor Java Applets WWW server End-user DM/AM local pages UM DM - Domain Model AM - Adaptation Model UM - User Model Manager 11

12 Design Requirement Adaptation Types and Techniques? Adaptive presentation Adaptive text presentation Adaptive multimedia presentation Natural Language Adaptation Inserting/ removing fragments Altering fragments Canned text adaptation Stretchtext Sorting fragments Dimming fragments Adaptation of modality Yes No Yes Yes Yes but may require AJAX No Yes Yes? Adaptive navigation support Adaptive link hiding Direct guidance Adaptive link sorting Hiding Disabling Removal Adaptive link annotation Adaptive link generation Map adaptation Possible, but tricky No Yes Yes Yes Yes No No New: Adaptive link destination technique Yes

13 AHA! engine Java servlets Design requirement adaptation types and techniques Pages from external WWW servers Authoring tools Concept Editor Graph Author Form Editor Java Applets WWW server End-user DM/AM local pages UM DM - Domain Model AM - Adaptation Model UM - User Model Manager 13

14 Design Requirement Aspects Used for Adaptation Domain model related information User related information (not related to DM) Environment data Represented via domain model and pseudo concepts and multiple attributes of these concepts 14

15 Design Requirement Arbitrary Concept Relationships Graph Author templates: Concept templates - concept types (e.g., page, object, abstract) - arbitrary attributes Concept relationship types templates - requirements for concepts - event-condition-action rules updating the UM 15

16 Design Requirement Arbitrary Concept Relationships Examples of relationships: Prerequisite Concept B is a prerequisite for concept A A.suitability : B.knowledge > 50 Interest Interest in concept B indicates interest in concept A A.suitability : B.interest > 50 16

17 AHA! engine Java servlets Pages from external WWW servers Authoring tools Concept Editor Graph Author Form Editor Java Applets WWW server End-user DM/AM local pages UM DM - Domain Model AM - Adaptation Model UM - User Model Manager Design requirements aspects used for adaptation & arbitrary concept relationships 17

18 Design Requirement Generic Adaptation Rules Rules tied to generic concepts Defined through the Graph Author concept relationship types templates Examples of generic concepts: Child-parent Source-destination 18

19 AHA! Graph Author Tool: Defining the Domain/Adaptation Model 19

20 AHA! engine Java servlets Pages from external WWW servers Authoring tools Concept Editor Graph Author Form Editor Java Applets WWW server End-user DM/AM local pages UM DM - Domain Model AM - Adaptation Model UM - User Model Manager Design requirement generic adaptation rules 20

21 Design Requirement Handling Non-monotonic User Model Updates and Cycles in Adaptation Rules Handling Non-monotonic User Model Updates Possibility to specify rules increasing/decreasing the attribute values of concepts Handling Cycles By making the order of rules execution visible in the Concept Editor tool By an automatic check for cycles in the authoring tools By limiting the number of objects included in a page 21

22 AHA! engine Java servlets Pages from external WWW servers Authoring tools Concept Editor Graph Author Form Editor Java Applets WWW server End-user DM/AM local pages UM DM - Domain Model AM - Adaptation Model UM - User Model Manager Design requirement handling cycles Design requirement non-monotonic UM updates 22

23 Design Wishes Authoring Tools high-level Graph Author low-level Concept Editor Performance AHA! achieves sub-second response time 23

24 Correlations Between CS/LS Riding s model Wholist Analytic Verbalizer Imager Serialist (W)holist Pask s model Dunn & Dunn model Visual Global Analytic... Felder- Silverman model Active Reflective Sensing Intuitive Visual Verbal Global Sequential Honey & Mumford model Activist Reflector... MBTI Extravert Introvert Sensor Intuitive... Witkin s model Field-dependent Field-independent Vermunt s model Meaning-oriented Application-oriented Reproduction-oriented Undirected Kolb s model Assimilating Accommodating... 24

25 Types of Adaptation Strategies Instructional strategies - selection of items - ordering information or providing different navigation paths Instructional meta-strategies inference or monitoring strategies, to detect user s learning style, e.g. preferences for: - certain types of information (e.g., text vs. image) - reading order (e.g., breadth-first vs. depth-first) 25

26 Learning Styles Strategies Structure in LAG-XLS strategy name description if+ then select? sort? setdefault* action* select attributename showcontent* showcontentdefault* showlink* showlink linkto comment sort attributename linkto* setdefault attributename expression if condition then else else select? sort? setdefault* action* action attributename UMvariable expression 26

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28 Presentation for Imager+Global Learner 28

29 Presentation for Verbal+Sequential Learner 29

30 Inferring Preferences for Image or Text 30

31 Presentation for Active Learner 31

32 Presentation for Reflective Learner 32

33 Approach Validation and Evaluation Representing features of AHS providing adaptation to CS/ LS in AHA! Evaluation with students from TU/e - understanding of how the system works - authoring ease - satisfaction with the resulting presentation Validation with learning styles experts - satisfaction with the effect of the predefined strategies - expressivity of LAG-XLS language for defining strategies 33

34 Conclusion We showed that it is possible to create a general-purpose AH tool We demonstrated the general-purpose nature of AHA! by showing adaptation to CS/LS: - support for CS/LS implemented as an extension to the created tool - no changes to the core engine were required 34

35 Future Work Address the option for searching information in adaptive applications Creating various types of strategies not only limited to cognitive/learning styles Group user models and adaptation: use information about some users to help others 35