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ESCAPEfrom
FREERIDERSJun Kobayashi (U of Chicago)
Hirokuni Ooura (Teikyo U)Hideki Ishihara (Rikkyo U)
August 21, 2003Marstrand, Sweden
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1 QUESTIONIn MODERN SOCIETIES…
We can CHANGE PARTNERS.
Divorce, Move, Change Job, Immigration.
COOPERATION in Dilemmas… when CHANGE PARTNERS?
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2 THEORYSELECTIVE INTERACTION (Dawes),ESCAPING (Hayashi).Prediction…ESCAPE COOPERATION.
But NOT SELF-EVIDENT… b/c Defectors FOLLOW.
CC
CDD
D
CD
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3 HYPOTHESES"ESCAPING TIT-for-TAT"…
TIT-for-TAT in a Group,EXIT when DEFECTED,Cooperate in NEW Group.
H1 SOME play "Escaping TFT."
H2Earn MORE than DEFECTORS.
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4 EXPERIMENTWEB-BASED.Repeat S.D. Game in a GROUP,MOVE to Anther Group, No COST.ANONYMOUS.
15-20 Subjects (students).20-40 Games, 3-6 Moves.
6 Sessions, 111 Subjects.2 Universities in Japan, Nov. 2002.
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5 GAMEWork at one of 4 FIRMS.If D (Work LAZILY), PAYOFF…
# Cooperators 4 .# Workers in FirmIf C (Work HARD), PAYOFF…
D's Payoff - 2.
# Cooperators
Payoff DefectionCooperation
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Your CHOICE, PAYOFFEach FIRM's
PAYOFF,#Workers
EACH MONTH
HOW to WORK?
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EVERY 6 MONTHS History of Each FIRM's PAYOFF,
#WorkersEach FIRM's AVERAGE PAYOFF
WHERE to WORK?
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6 RESULT
groupA groupB groupC groupD Σ Nc3 5 15 18 19 1 4 10 12 17 8 11 13 14 16 20 2 6 7 94 0 0 4 0 0 0 0 4 0 0 0 0 4 0 4 4 4 0 4 84 0 0 0 4 0 0 0 4 0 0 0 0 0 0 4 4 4 0 4 70 0 0 0 4 0 0 0 0 0 0 4 4 0 0 4 4 4 4 4 80 0 4 4 0 0 0 0 0 0 4 4 0 0 0 4 4 4 4 4 94 4 0 4 0 0 0 0 0 4 0 4 0 0 0 4 4 4 0 4 90 0 0 0 4 0 0 0 4 0 0 0 4 4 0 4 4 0 0 4 7
5 13 17 18 3 4 16 19 7 8 10 1 2 6 9 11 12 14 15 200 0 0 4 4 0 0 4 0 0 0 0 4 4 4 0 4 0 0 4 80 0 0 4 4 0 0 4 0 0 0 0 4 4 4 0 0 4 4 4 90 0 0 0 0 0 0 4 0 0 0 0 4 4 4 4 0 4 0 4 70 0 0 0 0 0 0 4 0 0 0 0 4 4 4 0 4 0 4 4 70 0 0 0 0 0 0 0 0 0 0 0 4 4 4 0 4 0 0 4 50 4 0 0 0 0 0 0 0 0 0 0 0 0 4 4 4 0 0 4 5
9 4 18 2 3 1 5 6 7 8 10 11 12 13 14 15 16 17 19 204 4 4 4 4 0 0 4 0 4 0 0 0 0 0 0 0 0 4 0 84 4 4 4 4 0 4 4 0 0 0 0 4 0 0 0 0 4 0 0 94 4 4 4 4 0 4 4 0 0 0 0 0 0 0 0 0 0 0 0 74 4 0 4 4 0 0 4 0 0 4 0 0 0 0 4 0 0 0 0 74 4 4 4 4 0 0 0 0 0 0 0 0 0 0 0 4 0 0 0 64 4 4 4 0 0 0 0 0 0 0 0 0 0 4 4 0 0 0 0 6
2 7 10 11 12 14 18 20 4 5 15 19 1 3 6 8 9 13 16 170 0 0 0 0 0 0 0 0 4 0 4 0 4 4 0 4 0 0 0 54 0 0 0 0 0 0 0 4 4 0 0 4 4 4 0 4 4 4 0 90 0 0 0 0 0 0 0 0 4 0 4 0 4 4 0 4 0 0 4 6
Mean SD
C .40 .24
Move .54 .24
Payoff .80 .38
6 Sessions111 Subjects-2 < Payoff < 4
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7 ESCAPING TFT? move
behav.
ESCAPE FIXED RANDOM total
TFT 30 10 8 48All C 1 4 1 6All D 7 3 2 12RANDOM 12 10 5 27
Other 8 8 2 18total 58 35 18 111
→YES!
27%
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8 BETTER? move behav. ESCAPE FIXED RANDOM total
TFT 0.77 0.90 0.80 0.80
All C 0.09 0.66 1.01 0.62
All D 0.91 0.87 1.39 0.98RANDOM 0.83 0.68 0.88 0.79
Other 0.74 0.87 0.25 0.74
total 0.79 0.80 0.84 0.80 →NO!
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9 CONCLUSIONCOOPERATION by ESCAPING?Something MORE.
Theory… MOVING COST.
Test… More Experiments / Surveys.