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Exploratory Model BuildingToward Agent-Based Economics
Takashi IbaMasaharu HirokaneHirokane KawakamiYoshiyasu Takefuji
Heizo Takenaka
[email protected] ://www.boxed-economy.org/
Post-Office Box 17, Fujisawa Keio-mae Post Office:4250-1 Endo, Fujisawa, Kanagawa, Japan, zip 252-0816
Keio University, Japan
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How Building Reality?
Possible World
FACT simulation
Model andInitial condition
result
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Incremental Development of the simulation model
Predictionor Explanation
ApplicationFeedback
Application
Feedback
Predictionor Explanation
Incremental D
evelopment
of the si
mulation m
odel
From the macroscopic viewpoint,
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Exploratory Model Building
• Model Building
• Model Specification– Specification of initial settings
• Parameter Estimation
• Model Validation
From the microscopic viewpoint,
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• Model Building
•cognitive science•social psychology•consumer behavior•marketing science•management science•artificial intelligence
•reinforcement learning•neural network
algorithm modelcomponent
meta-algorithmModel component
adaptivecomponent
agent modelcomponent
Phase 1Phase 1
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There are some alternative models.
Phase 1Phase 1
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• Model Building
•communication studies•social network analysis•Sociology•distributed artificial intelligence
agent modelcomponent
relation modelcomponent
composedsocial model
Phase 1Phase 1
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• Model Specification
Phase 2Phase 2
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Inductive Parameter Estimation
• Parameter Estimation
Phase 3Phase 3
Deductive Parameter Estimation
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Deductive Estimation(for Parameter or Model)
Phase 3Phase 3
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• Model Validation
• Comparison with observed data
• Comparison with other economic theories
• Comparison with empirical tendencies
Phase 4Phase 4
observeddata
other economictheories
empiricaltendencies
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Parameter Estimation and Model Validation
Phase 4Phase 4Phase 3Phase 3
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Total Flow of Exploratory Model Building
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AutomaticModel Estimation System
parameter rangeand increments
social modeldesigns
data set forvalidation
componentmodel designs
modelcomponent
data set
Permissioncondition
simulation user
inputs
automatic modelestimation system
outputs
a=20b=5.34x=0.02
a=98C=12000Z>12345
some combinations ofmodel settings
application
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For success with social simulation
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“Neo-Instrumentalism”
• Instrumentalism+
• Extensibility of model• Reality of the assumptions
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Open the Black Box !
Boxed Economy Model
= miniature of the entire economy