Thinking too much: Pathology in pathfinding

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Thinking too muchPathology in pathfinding

• Mitja Luštrek
• Jožef Stefan Institute
• Department of Intelligent Systems
• Slovenia

Vadim Bulitko University of Alberta Department of
Computing Science Canada
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Heuristic lookahead search
Lookahead area
Current state
Goal state
Lookahead depth
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Heuristic lookahead search
Heuristic
Known
Estimated shortest path
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Heuristic lookahead search
Estimated best move
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Conventional wisdom
Shallower lookahead ? worse move
Deeper lookahead ? better move
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Pathology
Shallower lookahead ? better move
Deeper lookahead ? worse move
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Pathology history and present

• Long known in two-player games Nau 1979, Beal
  1980
• We investigate it in pathfinding on maps from
  computer games

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We discover plenty of pathology

• Come see the poster
• to find out everything about it