qualitative modeling in education bert bredweg and ken forbus yeşim İmamoğlu
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QUALITATIVE QUALITATIVE MODELING IN MODELING IN EDUCATIONEDUCATIONBert Bredweg and Ken ForbusBert Bredweg and Ken Forbus
Yeşim İmamoğluYeşim İmamoğlu
Computers and Education
Using educational software Supports constructivism in education Allows multiple representations and
interaction Serves to individual differences
Qualitative Reasoning and Education
Qualitative reasoning is valuable for education because:
Uses of conceptual knowledgeWhat happens, when does it happen, what
effects it, what does it effect? Provides grounding and framework for
quantitative and traditional mathematical models
Recent Applications
Teachable Agents project (Vanderbilt University, Biswas et al. 2001)Betty’s Brain-qualitative mathematics
ALI (D’Sauza et al. 2001)Based on qualitative process theoryDomain independent-can be attached to any
quantitative simulation
Recent Applications
Application of qualitative process theory in chemistry classes (Syedd, Pang and Sharifuddin, 2002)Qualitative model is used alongside
classroom experiment to determine optimal use of substances
Aspects of modeling that existing visual languages do not address The importance of broadly applicable
principles and processes Understanding when a model is relevant Qualitative understanding of behavior
VModel
Student friendly visual notation for qualitative process theory
Creates a software environment that helps students express their qualitative, conceptual models
VModel Visual notation is based on concept maps Nodes represent entities and properties of
entities Each node has a specified type such as
Thing, Multiple Thing, Substance or Process
Quantities are used to describe the continuous properties of entities
Links represent relationships, labels are drawn from a fixed set of relationships
VModel Small, fixed set of structural relationships
Touches, Contains, Part of...
Ordinal relationships Greater Than, Less Than, Equal To
‘Requires’ relationship links a process to the conditions that enable it
Casual relationships Increases, Decreases: direct influences (I+/I-) Influences, InfluencesOpposite: qualitative
proportionalities )/( QQ
VModel Two coaches:
Qualitative simulation to help the students see how well their model make predictions
Modeling equivalent of spelling and grammar checking
Three sources of feedback: Visual step-by-step animation of the simulation English summary of behavior predicted by the model Assessment of how well the model supports the
hypothesis
VModel
Model library: contains all the models that the students have created
Students can build their own domain theory
HOMER and VISIGARP
Allow learners to use a qualitative reasoning engine for running and inspecting simulations
They work on top of the domain independent qualitative reasoning engine GARP
Use diagrammatic reprsentations for buliding and inspecting qualitative models and simulations
Model Building with HOMER Organized set of builders and tools Builders:
Capture knowledge and use diagrammatic representations
Used for creating building blocks (entitiy hierarchy, quantities, quantity spaces...)
Tools: Interactive dialogues for modifying the content of builders
Constructs: Model fragments and scenarios Assembled from building blocks
Model Building with HOMER Task:
Create a set of model fragments (stored in library) Specify one or more scenarios (structural description
of the system)
Model Building: Simulator uses the model fragments to predict the
behavior of the system defined in the selected scenario
For each of the specified scenarios, the simulator generates the intended behavior graph
HOMER Prevents learners from making syntatically incorrect models
The user interface restricts user actions based on Content Current selections in the builder that the user is
working on Investigates each user action with respect to
side-effectsNotifies the user Gives user the option either carry on with the action or cancel it
Problems encountered using HOMER
Homer was tested on two researchers and two
master students from a computer science
department Problems caused by poor use of the tool Problems caused by subjects not fully
understanding how to perform a task
(model building problems)
Model building problems Model scope:
Determining which features of the real-world sytem to include in the model
Model Structure: Determining what to put where in the model
Model Building Concepts: Understanding the meaning and difference between
the concepts provided by the tool Model Representations:
Knowing the concept, what to represent but not knowing how to represent it
VISIGARP
Provides a graphic interface to for running and inspecting qualitative simulations
Simulations might use models constructed by teachersdomain experts the learners (for example, by using HOMER)
VISIGARP
Visual container: All model ingredients belonging to a particular area are grouped into a single box
Ingredients relating aspects from different entities cross the border of the boxes
Usability of VISIGARP
Experiment was conducted to 30 first year university (psychology) students
Pretests and posttests were conducted on domain knowledge and icon language of VISIGARP
Treatment: Prediction exercises using simulations
Subjects were asked to evaluate VISIGARP after treatment
Usability of VISIGARPResults indicate that:
There was significant difference between pre/post tests in domain knowledge
No significant difference between pre/post tests in icon language
Most icons were easy to learn: ≤, <, =, ≥, P+, P-, I+, I- A few icons were hard to understand: Q^, Q, V^, V (they
were not used much during simulation) VISIGARP did not always produce insighful graphs for comlex
models Attitude test revealed that subjects evalated the usefulness of
VISIGARP quite positively
Conclusion
Importance of conceptual knowledge in education
Reasoning about system behavior Two qualitative models: VModel and
HOMER/VISIGARP combination Both foster learning as a constructive process
Comments Experiments are done with subjects at the
university level Further adjustments may be needed if it is
going to be used in high-middle school level (more user friendly)
Suitable for the new curriculum in Turkey, but not easy to put into practice