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A Reproduction Experiment Concerning the Relation Between Perceptual Features

and Memory in Shogi

Reijer GrimbergenDepartment of Informatics

Yamagata University

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OutlineWhere do we want to go?A reproduction experiment in shogiExperimental resultsConclusions and future work

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Where do we want to go?Using Marvin Minsky’s Society of Mind theory for game playingWhat are the primitive agents?

Input agents: perception of board and piecesOutput agents: playing moves

First stepStudying perception to understand input agents

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Hypotheses about perceptionHypothesis 1: It is easier to perceive one’s own pieces than the pieces of the opponent

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Hypotheses about perceptionHypothesis 2: It is easier to perceive pieces in hand than pieces on the board

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Hypotheses about perceptionHypothesis 3: It is easier to perceive pieces that are promoted than pieces that are not promoted

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Hypotheses about perceptionHypothesis 4: Pieces closer to oneself are easier to perceive than pieces further away

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Hypotheses about perceptionHypothesis 5: Bigger pieces are easier to perceive than smaller pieces

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Reproduction experimentSeven subjects

Early twentiesOnly rudimentary knowledge of shogi

Ten positionsEach hypothesis tested by using two positionsPerceptual features related to the other hypotheses identical

ReproductionEach position was shown for 5 secondsReproduce the position

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Reproduction experimentHypothesis 1: It is easier to perceive one’s own pieces than the pieces of the opponent

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ResultsHypothesis 1: It is easier to perceive one’s own pieces than the pieces of the opponent

Subject Position 1 Position 2S1 Opponent piece Own pieceS2 Own piece Own pieceS3 Own piece Opponent pieceS4 Own piece Opponent pieceS5 Opponent piece Own pieceS6 Own piece Opponent pieceS7 Opponent piece Own piece

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Reproduction experimentHypothesis 2: It is easier to perceive pieces in hand than pieces on the board

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ResultsHypothesis 2: It is easier to perceive pieces in hand than pieces on the board

Subject Position 3 Position 4S1 Board piece Board pieceS2 Board piece Board pieceS3 Board piece Board pieceS4 Piece in hand Board pieceS5 Board piece Board pieceS6 Board piece Board pieceS7 Board piece Board piece

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Reproduction experimentHypothesis 3: It is easier to perceive pieces that are promoted than pieces that are not promoted

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ResultsHypothesis 3: It is easier to perceive pieces that are promoted than pieces that are not promoted

Subject Position 5 Position 6S1 Promoted piece Promoted pieceS2 Unpromoted piece Promoted pieceS3 Promoted piece Unpromoted pieceS4 Promoted piece Unpromoted pieceS5 Unpromoted piece Unpromoted pieceS6 Unpromoted piece Promoted pieceS7 Unpromoted piece Promoted piece

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Reproduction experimentHypothesis 4: Pieces closer to oneself are easier to perceive than pieces further away

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ResultsHypothesis 4: Pieces closer to oneself are easier to perceive than pieces further away

Subject Position 7 Position 8S1 Close piece Close pieceS2 Close piece Close pieceS3 Close piece Close pieceS4 Far piece Far pieceS5 Close piece Far pieceS6 Close piece Close pieceS7 Far piece Far piece

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Reproduction experimentHypothesis 5: Bigger pieces are easier to perceive than smaller pieces

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ResultsHypothesis 5: Bigger pieces are easier to perceive than smaller pieces

Subject Position 9 Position 10S1 Bigger piece Smaller pieceS2 Bigger piece Smaller pieceS3 Smaller piece Bigger pieceS4 Smaller piece Bigger pieceS5 Bigger piece Smaller pieceS6 Bigger piece Smaller pieceS7 Bigger piece Smaller piece

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ConclusionsHypothesis 1 and 3 must be discarded

No evidence that one’s own pieces are easier to perceive than the pieces of the opponentNo evidence that promoted pieces are easier to perceive than non-promoted pieces

Hypothesis 2, 4 and 5 unclearSize, closeness and the difference between pieces in hand and on the board may be factors influencing perception

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Future WorkFurther investigate hypotheses

Increase the number of subjects

Primary assumption correct?Are pieces that are reproduced first really easier to remember?

Build a working system