Debugging, The Scientific Method, and Mastermind

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Debugging, The Scientific Method, and Mastermind
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The Scientific MethodBuilding a Model of Our
World
Getting inside the black box
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Building a General Model
What causes cancer?
We ask a series of questions, conduct
experiments, and try to associate cause and
effect.
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Diagnosing Specific Cases
What is wrong with this patient?
Now, in a specific case, we conduct tests and
compare the answers to the disease model that we
have already built.
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Diagnosis A Different Domain
Whats wrong with the car?
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Whats Common to These Examples?

• Theres some underlying situation.
• We cannot directly observe the entire system.
• But we can probe it with specific questions.
  The answers we get help us to build a more and
  more complete model of the system.
• We want to ask as few questions as possible in
  the process.
• Why?

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So How Should We Choose Our Questions?
We want to find a specific location in this
territory. Whats the most efficient way to
proceed?
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With Each Answer We Get a Better Model

• Begin with an initial model that is as rich as
  possible.
• Loop until only one possible answer remains
• Based on what we know so far, choose a question
  that cuts out as many possibilities as we can.
• Use the answer to build a better model.

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Mastermind The Game
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How To Play

• Player 1 creates a pattern of colors in her 4
  holes (the inside of the black box).
• Player 2 must discover the pattern through a
  series of guesses (experiments) and replies
  (results). At each move
• Player 2 puts down a candidate pattern.
• Player 1 replies with a set of black and white
  pegs
• Each black peg corresponds to a peg in the right
  place.
• Each white peg corresponds to a correct peg in
  the wrong place.

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An Example
If the secretsequence is... If the secretsequence is... If the secretsequence is... If the secretsequence is... Andyour guess is... Andyour guess is... Andyour guess is... Andyour guess is... Your scorewould be...
                                                                                     
                                                                           
                                                                           
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You Can Play Online
http//www.irt.org/games/js/mind/