Recap and Overview of Simulations

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Recap and Overview of Simulations

• CEP 806/914
• February 21, 2001

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School Science vs. Practiced Scienceaka.
Houston We have a problem .

• School Science
• Theories (models) are presented
• Data is presented in support of the theory
  (model)
• Theories (models) are proved as true, or
  factually correct
• Theories (models) are rigid
• Science as practiced
• Theories (model) are created
• Theories (models) are a conceptual undertaking
  (as well as empirical)
• Data is for evaluating fit
• Theories (models) are in flux

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Science as Theory Building

• NOTE - The views presented here are overly
  simplified. Science isnt really this clean cut,
  as the fields of science history and philosophy
  of science have pointed out. But, this has some
  utility that we will use here.

Collect Data
Use Theory Or Teach to Kids
Revise Theory
Make a Theory
Evaluate Theory
NOTE Science Ed is often reduced to
dissemination of theories, and not all the cool
stuff on the right. Most reform efforts seek to
remedy this situation by including some or all of
the stuff to the right.
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Science as Theory Building

• There is some phenomena or system that could be
  better understood
• The motion of objects
• The functioning of a body organ
• How altruism can have an evolutionary explanation
• How termites can build a mound with limited
  intelligence

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Science as Theory Building

• Collect observations (data)
• Measure the luminosity and positions
  of stars (e.g. Tyco Brahe)
• Collect field information about species diversity
  (e.g. Darwin)
• Measure time and position of falling objects
  (e.g. Galileo)
• Dissect animals to collect information on the
  characteristics of bodily organs
• Etc.

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Science as Theory Building

• Now, simply make a theory ) In other
  words, mix together
• One part logic
• One part art
• One part inspiration
• One part insight
• One part magic (the part that nobody understands)

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SIDEBAR - Whats a theory

• We build the theory because we wish to understand
  something. Indicators of this understanding
• Predict
• Explain
• Control
• Simplify
• Theories have many forms
• Text (e.g. Darwin) - Mutation and Selection drive
  the evolution of species
• Equations (e.g. Newton) - FmA
• Analogies
• Models (e.g. Keppler)
• Simulations (e.g. Start of the universe models)

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Science as Theory Building

• Theories are Evaluated. Usually through
  comparisons to existing data. Or by running
  experiments. How well do they ____________ ?
• Predict
• Explain
• Simplify
• How do they compare to rival theories?
• Which theory accounts for the data? (empirical)
• Which theory explains better? (conceptual)
• Which is more compelling?
• Do they make different predictions in some (yet)
  untested condition?

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Science as Theory Building

• Theories are revised
• To better predict
• To better explain
• This often necessitates collecting more
  observations and starting the cycle all over
  again.

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Simulations

• Most broadly, refer to any virtual experience.
  Many of which are not particular to science
• Online communications (virtual community)
• Art (virtual depictions)
• Training (Flight simulators)
• The rest of this presentation focuses on
  simulations in science education

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Simulation in Science Education

• Observing and collecting data
• Collecting data virtually for data that is hard
  to get during school hours (e.g. star positions)
• Training for collection procedures (e.g. cow eye
  dissection)
• Theory Building
• Having kids write simulations as embodiments of
  theories (e.g. Star Logo, Model_It! )
• Theory Evaluation
• Getting data faster - Virtual lab environments
  where you can run experiments much faster than
  the real world
• Conducting experiments - Simulation makes
  predictions for certain conditions. Could compare
  results to real world.

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Simulation in Science Education

• Theory Revision
• Same as Building and Evaluation above
• Teaching Theories
• Making tradition teaching of theories come alive,
  by linking phenomena to the the theoretical
  explanations and representations. (e.g. DiSessas
  Physics World, Snirs density world, etc.)

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Pro and Cons of Simulation 1

• PRO Simulations afford the opportunity to do the
  otherwise impossible, difficult, or impractical
  (e.g., launch a rocket, Dissect a Dodo bird)
• CON
• Impossible May distort reality for students
  (e.g. shooting people in video games is rewarded)
• Difficult May also distort reality when
  difficult things are commonplace.
• Impractical Virtual pendulum, why not a real
  pendulum

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Pro and Cons of Simulation 2

• PRO Simulations can focus on the relevant, and
  ignore the irrelevant (i.e. they can make the
  phenomena more ideal)
• Physics - Movement of objects without friction
• Biology - Distinctive body parts that are easier
  to identify
• CON
• Who gets to decide whats relevant?
• What if the irrelevant is relevant?
• Danger of oversimplifying
• Confusing the theory with reality (Reality is
  more complex
• Hiding the process of construction underlying
  theories and models

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Pro and Cons of Simulation 3

• PRO Simulations can allow students to make
  manipulations and see their effects
• Opens up the process of theory (model) building
  and evaluation
• Invites students to see causation between the
  mechanisms in the model and the effects on the
  phenomena
• CON
• Misrepresenting Reality Manipulations might not
  be possible in the real world (You cant change
  the mouth on an existing fish like you can in the
  virtual aquarium)
• Cognitive overload requires reasoning about
  multiple causations, which may overload students
  cognitive capacities.

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Pro and Cons of Simulation 4

• PRO Simulations can make stuff that is hidden in
  the real world visible in the simulation (e.g.
  vectors of momentum, a trail of movement, color
  to represent temperature, etc).
• Theories become visible
• Connections between the accepted notations and
  the phenomena being modeled.
• CON
• Correspondence Lack of correspondence between
  reality and the simulation (far too many to
  mention).
• Obscures the process of deciding what to make
  visible, and what representations are profitable
  for that phenomena (dependent on the developer of
  the system).

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Pro and Cons of Simulation 5

• PRO Allows theory building and modeling to be
  more visible accessible, assessable, and sharable
  to all.
• Connections between the sterile theory and the
  rich phenomena becomes more accessible (e.g.,
  Newtonian billiard ball simulations).
• Requires theories to be fully specified.
• In some cases, the simulations become so
  accessible, that children can make them (e.g.
  StarLogo).
• CON
• Immersive The simulation can be so compelling,
  students can forget to ask important questions
  like Whos doing the theory building and
  modeling? Why should I believe them?

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Does Simulation Theory ?

• It can be
• Most scientific simulations explicitly or
  implicitly embed a theory (Newtonian physics,
  water cycle, movement of the solar system, etc.)
• But not necessarily
• Example Cow-eye dissection. There isnt a theory
  (in the explanatory sense) embedded in the the
  simulation. Its more of a virtual training guide
  to a scientific procedure to be performed.

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Does Simulation Model ?

• I think a simulation is a model
• Every simulation has a simplified world, a model
  of some more complex system. This includes the
  cow-eye dissection (the model eye is less messy
  than a real one).
• A model doesnt have to be a simulation
• For example, a model airplane (to scale) doesnt
  simulate anything about a real plane (other than
  the relative proportions and positions of real
  plane features). It doesnt virtually fly,
  predict when it would stall out, its terminal
  velocity, nor its stability.
• A theory might be the same as a conceptual model

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Does Theory Model ?

• It often does
• Most theories have models that instantiate them
  (Newtonian physics has plenty of models that
  behave accordingly - for example DiSessas moving
  ball model, Evolutionary theories have many
  associated models - we saw some in StarLogo).
• Doesnt have to be
• Model w/o a theory - Example model airplane (to
  scale).
• Theory without a model - Constructivism as an
  educational theory (Although one might argue
  that the development of the theory is not far
  along enough to warrant the creation of a model
  yet).

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The End ?

• Questions, comments, criticisms, critical
  acclaim, ?