Multipurpose Strategic Planning In the Game of Go

1
Multipurpose Strategic Planning In the Game of Go

• Paper presentation
• Authors Shui Hu and Paul E. Lehner
• Presentation by Adi Botea

2
Outline

• Introduction
• Description of the Approach
• Example
• Conclusion

3
Introduction

• Go strategy tactics
• Current Go programs
• Valuable work in tactics BUT
• Lack of strategic focus
• So, this paper proposes
• Strategic tactical planning in Go
• A new approach on multipurpose moves

4
General Description of the Approach

• Static analysis to determine possible goals
• Dynamic look ahead to further estimate goal
  consequences
• Evaluate goals and goal interactions
• Select the best strategy (goal or set of goals)
• Perform detailed look ahead to find the best way
  to implement the plan

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More Details on Approach

• Object hierarchies
• Stones, strings, chains, and groups
• Current Goal Structures (CGSs)
• Hierarchies that characterize goals that may be
  pursued in a given position

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Current Goal Structures
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Static Goal Generation
Example of strategic goal definition
Example of tactical goal definition
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Look Ahead Algorithm

• Similar to tactical search
• Goal Stacks for both players
• Given a hypothetical position

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Goal Achievability Composition
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Planning Procedure
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Example - ORSIM
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Example ORSIM (cont.)
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Example ORSIM (cont.)
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Conclusion Results

• Multipurpose planning in Go
• Includes strategy formalization
• Catches interactions between moves
• Reasonable computational complexity
• Planner is very strong on selected problems