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@ -37,7 +37,7 @@ Ex CSP problems: |
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## Problem formulation |
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### Variables |
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@ -64,17 +64,17 @@ Nodes in graph are variables, arcs show constraints |
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## Backtracking |
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### Minimum remaining value |
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Choose the variable wit the fewest legal values left. |
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### Degree heuristic |
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Tie-breaker for minimum remaining value heuristic. |
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Choose the variable with the most constraints on remaining variables. |
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@ -83,36 +83,36 @@ Choose the variable with the most constraints on remaining variables. |
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Choose the least constraining value: one that rules out fewest values in remaining variables. |
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### Forward checking |
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Keep track of remaining legal values for unassigned variables and terminate search when any variable has no legal values left. |
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This will help reduce how many nodes in the tree you have to expand. |
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### Constraint propagation |
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### Arc consistency |
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### Tree structured CSPs |
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Theorem: if constraint graph has no loops, the CSP ca be solved in $O(n*d^2)$ time. |
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General CSP is $O(d^n)$ |
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## Connections to tree search, iterative improvement |
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To apply this to hill-climbing, you select any conflicted variable and then use a min-conflicts heuristic |
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to choose a value that violates the fewest constraints. |
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# CH 13: Uncertainty |
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@ -163,8 +163,8 @@ Eg: P(tired | monday) = .9. |
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## Bayes rule |
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## Independence |
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