SYSTEM DYNAMICS

1
SYSTEM DYNAMICS

• SOCQUIT Modelling Methodology

Rutger Mooy, TNO Sevilla, June 2004
2
Introduction
1957 Industrial Dynamics 1960/70s Development
at MIT 1970s Scenario Planning (Shell) 1972
Club of Rome / Limits to Growth 1990 The
Fifth Discipline 2000 Business Dynamics
3
The Method
System Dynamics analyzes complex feedback systems

• Key Principles
• Measure change over time
• Look at the system as a whole
• Take feedback and delays into account
• Combine mental models

4
System Dynamics is an iterative discipline!
Mental Model
Conceptual Model
Hypothesis
Start
Formal Model
Behaviour-over-time
Quantified Model
Simulation
Data
Verification Validation
5
Why SD?

• SD makes relationships explicit, clear and
  easy-to-understand
• SD produces a validated quantitative tool
• SD combines different views
• SD can deal with both hard and soft
  variables
• SD is flexible and may be combined with other
  disciplines (e.g. statistics for validation)
• SD can be easily documented

6
Conceptual Model
Quality of Life

• Goal

• Indirect Effects
• Basic Needs
• Human Capital
• ...

Social Capital

• Personal characteristics
• ICT characteristics
• ...

ICT Adoption and Use

• ICT-related Policy

7
Model Example
Quality of Life
Social Capital
Effect of trust on number of cooperative
activities
8
Modelling Issues

• We need to focus on practical questions
• We need to specifically address policy issues,
  not model the system as a whole
• We need to build a practical tool from the model
• We need to model causal, not (only) statistical,
  relationships