CS代考计算机代写 AI PowerPoint Presentation
PowerPoint Presentation
Semantic Networks
Semantic Networks
Generate and Test
Problem Reduction
Means-Ends Analysis
Fundamentals
Production Systems
Lesson Preview
Knowledge representations
Semantic networks
Problem-solving with semantic networks
Represent & Reason
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The relationships between the pieces and the transformations between the frames.
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Structure of Semantic Networks
Lexically: nodes
Structurally: directional links
Semantically: application-specific labels
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Characteristics of Good Representations
Make relationships explicit
Expose natural constraints
Bring objects and relations together
Exclude extraneous details
Transparent, concise, complete, fast, computable
Guards & Prisoners Problem
Also known by other names (cannibals and missionaries, jealous husbands, brothers and sisters).
Originally appeared in the 1200-year-old text Propositiones ad Acuendos Juvenes.
Used by throughout AI for problem representation.
Guards & Prisoners Problem
Three guards and three prisoners must cross river.
Boat may take only one or two people at a time.
Prisoners may never outnumber guards on either coast, though prisoners may be alone on either coast).
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Exercise: How many moves does it take to move everyone to the other side?
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Is this the right answer to the problem? ο Yes ο No
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Is this the right answer to the problem? ο Yes ο No
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Transformation #1
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Similarity Weights
5 points Unchanged
4 points Reflected
3 points Rotated
2 points Scaled
1 points Deleted
0 points Shape Changed
Similarity:
6 points
Similarity:
3 points
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Similarity Weights
5 points Unchanged
4 points Reflected
3 points Rotated
2 points Scaled
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0 points Shape Changed
Assignment
How would you use semantic networks to design an agent that can answer Raven’s Progressive Matrices?
To recap…
Representations
Semantic networks
Represent & Reason
Weights with Represent & Reason
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What is the answer to this problem?
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What is the answer to this problem?
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cost: 1
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Horizontal Reflection
180° Rotation
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Horizontal Reflection
180° Rotation
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What would the answer be? ο 2 ο 6
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