complex adaptive systems, computational social science and irregular warfare rob axtell chair,...
Post on 21-Dec-2015
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Complex Adaptive Systems,
Computational Social Science
andIrregular Warfare
Rob AxtellChair, Dep’t. of Computational Social Science
George Mason Universityand
External Professor, Santa Fe Institute
Outline
Complex Adaptive Systems (5 minutes)
Computational Social Science (5 minutes)
Computational Public Policy (5 minutes)
Regular Warfare as Simple (5 minutes)
Irregular Warfare as Complex (5 minutes)
Modeling Irregular Warfare (5 minutes)
Complex Systems Thinking
Nonlinear dynamical systems (math):
Chaos (high irregularity from low-dimensional, deterministic system)
Distributed, decentralized systems (CS):
Complexity (simple regularity from high-dimensional, stochastic system)
Early Ideas of Complexity
(Santa Fe Institute style)
Physicists + computer scientists + economists + biologists (evolutionary, ecological)
Artificial life (von Neumann -> Burks -> Langton)
Self-organization, emergence, spontaneous order (including self-organized critical systems)
Evolutionary algorithms, genetic programming
Artificial markets, artificial societies
Social Complexity: Micro
Heterogeneous agents
Bounded rationality
Interaction through networks
Action away from equilibrium
Realized computationally
Social Complexity: Macro
Social systems are multi-level systems
Agent modeling is a macro-scope (C Langton)
Can’t infer properties of the macro from the micro specification: fallacy of composition
Can’t infer properties of the micro (agents) from what emerges at the macro-level: fallacy of division
Social sciences are the hard sciences (H Simon)
Simple ➜ Complex(20th C) (21st C)
Single decision-maker
Scalar value function, first-order conditions, numerical solutions
Decision theory
Mean field, averages
Equilibrium, fixed point theorems
Continuous, smooth mathematics
Command-and-control
Multiple agents
Heterogeneous utilities, purposive behavior, agent models+simulation
Game theory
Networks, extremes
Volatility, adaptation, co-evolution
Discrete mathematics, computation
Bottom-up emergence
Agent Computing
Population of adaptive software objects...
...That interact socially
...Following (simple) rules of behavior
...Macrostructure EMERGES from the interactions of the agents
OR ⊂ MAS
Operations ResearchSingle formal representationExtremize scalar value functionYields normative prescriptions (policies)
Agent modeling/Multi-agent SystemsEach agent has its own internal model......and acts to improve its value functionKey: what emerges at the social level?Both positive and normative aspects
Agents in Practice
Abstract models: Sugarscape
Empirical models: ‘Artificial Anasazi’
Policy-relevant models: 3 1/2 successes
Traffic
Epidemiology
Combat
Finance
SugarscapeAbstract model for developing intuitions
Simple agents who
forage for resources on a landscape
Emergent order
Simple maize-growers who occupied the Colorado Plateau for 1000 years
Disappeared c 1300
Artificial AnasaziEmpirical model for generating explanations
Pre 9-11: Mathematical
Post 9-11: Computational
Smallpox (White House)
SARS (WHO)
Flu (HHS)
Policy-makers have driven the adoption of computational tools
EpidemiologyPolicy model for making predictions
Finance
NASDAQ used to trade in 1/8s and 1/16s
SEC req’d decimalization
NASDAQ management commissioned an agent simulation in ADVANCE of the rule change
Predicted 6 of 8 statistical changes
Regular Warfare: Simple
Lanchester equations model force-on-force annihilation
Can be calibrated for hand-to-hand combat, armored combat (e.g., tank v tank), etc.
Warfare has evolved!
Regular vs Irregular Warfare
Regular warfare is like a parade: choreographed, scripted, orchestrated
Irregular warfare is like city life outside the parade: distributed, wild
Need to understand the society in which irregular war happens
Irregular Warfare is a Complex Adaptive
SystemAgent-based combat an active area of researchAgent models are new way to do social scienceThey are capable of representing ALL the main ideas of complex adaptive systemsBut we are very far away from complete models in social science
Agent Models for Afghanistan
Origin and growth of the Taliban
Poppy agriculture/opium production
IED construction, placement, sensing
Most GIS-savvy
What is Needed?
Better behavioral, cognitive, neural models: experimental economics, cog sci, neuroscience
Better social process models: tribal dynamics, identity choice, growth
More HSCB research
Coherent 10 year research effort req’d.
Digression on Research Funding in Economics
NSF:Math/Physics: $1.5BOcean + Polar: $1.0BSocial, Behavioral and Economic Sciences: $250MSocial+Economic Sci: $100MEconomics: $30M
Macro+Finance: $5-6M
Fed: $50-100M
Treasury + SEC: $0Cost of the Financial
Crisis: $2-20T
What is Not Yet Possible in Irregular
WarfareHigh-fidelity models
Prediction of point outcomes, e.g., specific event @ (x, t)
Small N forecasting
Quantitative comparison of tactics
Long run prognostication
How to Tell the Possible from the
ImpossibleProject team is majority physicists, computer scientists and engineers
Discussion focuses on IT
Behavior, is ‘representative,’ not variegated (e.g., SD)
Output is mostly ‘eye candy’
No matter what you ask for they can model it (i.e., no sense of hard vs easy tasks)
Unwillingness to ‘open source’ their code
Summary
Agent models, grounded behaviorally, are the way social science will be done, eventually
They are ‘normal science’: abstract, empirical and predictive/policy versions all possible
Problem is not that the methodology is limiting--there is nothing it can’t do!
Bottleneck is cognitive/behavioral foundations
Snake oil salesmen are out there!
A large, many-year research effort is needed