Using Model Structure Business Structures 6k B John Hayward - - PowerPoint PPT Presentation

Exploring System Behaviour Using Model Structure

John Hayward

School of Compu?ng & Mathema?cs University of South Wales, UK

john.hayward@southwales.ac.uk

19th UK System Dynamics Chapter Annual Conference – April 2017

Behaviour

Business Structures

Years

3k 6k 25 50 75 100

Business Structures

Speed up + Slow Down - R B

Loop Impact

R B R B

+ +

• Balancing Behaviour

Dominant Loop

Reinforcing Behaviour

Dominant Loop

Reinforcing Behaviour

Largest Contributory Loop

Reinforcing Behaviour

Dominant Loop Set

Reinforcing Behaviour

Dominant Loop Set

Stella Architect

hKps://exchange.iseesystems.com/ Search: Loop Impact Select: Limits to Growth Archetype Play

Structure -> Behaviour

• 1. What behaviour do we seek to explain?

Stocks – Curvature (speed up +, slow down -)

• 2. What structures do we use to explain it?

Feedback Loops (R, B)

• 3. How do we measure the effect of a structure?

Loop Impact – RaDo measure of change

• 4. How do we decide which structure is dominant?

Dominant Loop Set, alternaDvely: largest contributory loop

Impact

A B Flow A Flow B

Impact of Loop on A = Change in Flow A Change in A = Change in Flow A given change in B X Change in B Change in A Impact of Loop on A X Impact of Loop on B = Loop Gain