Causal Loop Diagrams (CLDs)

Question 1

What is a CLD?

Answer 1

It is a diagrammatic representation if interacting elements in a systems model that focuses on capturing causality and feedback effects, and help in understanding the basic model of system.

Question 2

Are CLDs qualitative or quantitative?

Answer 2

They are qualitative in nature and NOT FOR QUANTITATIVE ANALYSIS.

Question 3

Components of a CLD: (4)

Answer 3

• Variable – items of interest in the model
• Causal link – indicates which event causes another
• Polarity – positive and negative
• Feedback loops – reinforcing (+) or balancing (-)

Question 4

What must be considered in terms of variables? (3)

Answer 4

® Use nouns not verbs —> “Costs” instead of “increasing costs”
® Should be able to vary over time —> “happiness” instead of “state of mind”
® Use the positive or negative form/sense of an element —> “growth” instead of “decay”

Question 5

What must be considered in terms of causal links? (3)

Answer 5

• Represented by an arrow
• Must be causality
• Ambiguous links – generally means that there are more causal loops (eg. price and revenue)

Question 6

What does polarity indicate?

Answer 6

Indicates the direction the affected variable moves as a result of the cause variable.

Question 7

What is a positive polarity?

Answer 7

Positive: If all else remains the same, an increase in the first variable, increases the 2nd variable above where it would have otherwise been had we not modified it.

Question 8

What is a negative polarity?

Answer 8

Negative: If all else remains the same, an increase in the first variable, decreases the 2nd variable below where it would have otherwise been had we not modified it.

Question 9

What can a feedback loop do?

Answer 9

Can change system behaviour

Question 10

• _____ loops –> positive feedback
• Balancing or _____ loops –> negative feedback
• ____ signs of polarities in loop

Answer 10

Reinforcing
regulating
Multiply