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Agent-Ba Base sed Sim imula lation ion
Dagstuhl Seminar „Modeling and Analysis of Semiconductor Supply Chains“ February 10th, 2016
is Lorsc rsche heid id Hamburg burg University iversity of Techn hnology,
rmany any www.tuhh. tuhh.de de/mac /maccs cs - Institute titute of Mana nage gemen ent t Accounting counting and Sim imula lation tion
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A few words about myself… Current research
– Using Structural al Equation
LS) to emp mpirical ally y valida date e agent architec ectures res (see, e.g., Lorscheid et al. 2014) and to analyz yze simulated d data (see, e.g., Mertens et al. 2015). – Developing standards rds for the design n of simulation n experime riment nts and analys ysis s of (complex) simulation models (see, e.g., Lorscheid et al. 2012, Lorscheid and Meyer in press). – Learni ning g agents for human complex systems (see, e.g., Lorscheid 2014).
Community
– European Social Simulation Association (ESSA)
http://www.essa.eu.org
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Perspect ctive ives s on agent-base sed sim imula lation ion and it its contr tribu ibution tion Analyzing Emergence Incorporating human behavior Using artificial agents
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About emergence…
- https://www.youtube.com/watch?v=KGeg
mMWsgu8
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Fir irst step: Underst rstand anding ing in indiv ividu idual l behavio vior Decision rules:
- 1. Separation - avoid crowding neighbors (short range repulsion)
- 2. Alignment - steer towards average heading of neighbors
- 3. Cohesion - steer towards average position of neighbors (long range
attraction)
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Sim imula lation: ion: Flo lockin king behavior vior
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Syste tem m Behavio avior r is is t the Result lt of Indiv ividu idual l Actio ion
Agent behavio avior Macr cro level vel Micr cro level vel
Behavior rules Preferences Perceptions (Information) Communication Interaction of individuals
System success? Individual Strategies
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„If you grow the phenomena you‘ll understand how it works.“ Joshua M. Epstein Through the bottom-up design, self lf-org
nization tion and emergent nt processes sses may evolve that are not explic licit itly ly modelled lled (or even understood by the modeler!) Macal
and North 2010
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Perspect ctive ives s on agent-base sed sim imula lation ion and it its contr tribu ibution tion Analyzing Emergence Incor
ating ing huma man n be behavio vior Using artificial agents
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Agent
- Representing the decision rules of the
agent explicitly
- Representing the interdependencies
between the different human activities
- Modelling the individual heterogeneity
- f agents
social re-/proactive autonom. adaptive Environment Action Perception Agent Agent attributes Decision rules, Preferences, Perceptions
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What are the effect cts s of varying ying decis isio ion models? ls?
- Approaching more complex („human“) behavior models…
- Perfect / rational
Agents Human decision makers
- decision maker
- (homo oeconomicus)
- … to explore possible consequences
Preferences, Information, Condition -> Action Rules etc.
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How w do we in inform m the decis isio ion n makers s wit ith ABM?
- 1. ABM asks new questions, like:
– What are the individual strategies? – What is the „human factor“ in your processes? – What are the interactions?
- 2. Implementation of findings in an ABM to analyze the
effect.
– How big is the difference that it makes? – How robust ist the system? – What are better ways of designing your environment? ABM is about understa standing nding the effects of human behavior to change (vs. tool to support local decisions)
Empirical study Modeling & Simulation study
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Under erst stand and huma man n behavior vior to design ign your ur envir iron
ment! nt!
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Under erst stand and huma man n behavior vior to design ign your ur envir iron
ment! nt! „As well as you need to make sure that people escape safely, you need to give them tools to make sure that they not get stucked in planning.“
- 1. Understand human (re-)actions.
- 2. Design your walls and columns!
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How to unde derstand stand human behavior?
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How w to understa stand nd human man behavior vior?
- Surveys, interviews, lab experiments
- Using theories, such as
– Prospect theory (Kahnemann/Tversky 1979) – Learning algorithms – See: Bounded rationality / behavioral economics
– Using structural equation models for agent modeling (Lorscheid et al. 2014: The PLS Agent - Agent Behavior Validation by Partial Least
- Squares. Social Simulation Conference)
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Examp mple le from m the Infin ineo eon n project: ct: Supply ly chain in pla lanner
Field Research Personal Experience Qualitative Research General IFX Information Flow Work Shadowing Interviews
(Blumberg and Atre (2003) estimate that around 85% of business information does not exist in a structured way)
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The in influ luencing cing facts s of a d decis isio ion (Infine fineon
What are central aspects of planning, affected by human decisions?
deviations?
situations? (beyond pressing the button)
to act?
Decision Behavior
IFX Planning Processes Planning Tools Planning Reports Rules/ Guidelines/ Targets Personal Experience Business Environ- ment Product Specifics Work Environ- ment
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Dir irect in interactions tions of the pla lannin ing agent
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Data collec llectio ion n research ch design ign
Information Content
Scientific Literature Qualitative Research Infineon Processes Conceptual Model Modelling & Simulation
Continuous development & improvement of the current IFX processes
Level of Detail
Königer 2016
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How to mode del human behavior?
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Sim imple le agent archit itectur cture
Agent Environment S A a x Rules f(x) = a
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Learning ing as addit itio ional l featur ure e to in increase se autonomy
x state of the environment y new enviornmental state z hidden factors influencing the
- utcome of the agents’ decision
r reward a agents‘ action
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Category egory Divisi sion Manager er Learn arning model el requireme ements (A) K Knowledge
- True productivity value
- Interval of possible
productivity values
- Resources
- Compensation value
- Reported productivity of
- pponent
Values in knowledgebase [R1.a]
behavior Belief [R.1b] (B) Prefer ference ces Maximizing the compensation Profit maximization [R2] (C) Reaso asoning strategy Report with highest expected individual payment Best expected individual utility [R3] (D) Experie rience ce collect ction
Implicit experience collection[R4.a]
experience Explicit experience collection [R4.b] (E) E Exploration strategy
Random exploration [R5.a]
- Systematic exploration of
under-, overestimation, and truthful reporting Systematic exploration [R5.b] (F) Pay ayoff ff Incentive scheme defines positive payments only. Positive payoff [R6]
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Behavior models
Behavior Model Learning Algorithm Knowledge base Random Zero Intelligence #,# → report BehM1 Sarin Vahid #,# → report BehM2 Sarin Vahid productivity, # → report BehM3 Ficticious Play productivity, prediction → report Rational
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Behavior models
Behavior Model Learning Algorithm Knowledge base Random Zero Intelligence #,# → report BehM1 Sarin Vahid #,# → report BehM2 Sarin Vahid productivity, # → report BehM3 Ficticious Play productivity, prediction → report Rational
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Results under varying incentives
Effect of adapted incentives
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Perspect ctive ives s on agent-base sed sim imula lation ion and it its contr tribu ibution tion Analyzing Emergence Incorporating human behavior
How to understand human behavior? How to model human behavior?
Usin ing artif ific icia ial l agents
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The variety of agents…
- Agent may vary from very simple condition-action patterns to
complex, intelligents entities. Agent as „Softbot“ Robot without a body
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Artif ific icia ial l Intellige lligence ce
Russel and Norvig 2009, p.2
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Agents s may fin ind good solu lutions! ions!
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Agents s may fin ind good solu lutions! ions!
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Perspect ctive ives s on agent-base sed sim imula lation ion and it its contr tribu ibution tion Analyzing Emergence Incorporating human behavior
How to understand human behavior? How to model human behavior?
Using artificial agents
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Finally…
Incorporate human behavior in your models: „…this complexity exists, if you wish it away or not!"
(Ken, in a different context)
Reader: ;-)