Public Policy Modeling
Examples of
Causal Loop Diagrams
Monday, July 31, 2017
Hun Myoung Park, Ph.D.
Public Management & Policy Analysis Program
Graduate School of International Relations
Software for CLD
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Vensim (https://vensim.com/)
iThink (http://www.iseesystems.com/)
STELLA (http://www.iseesystems.com/)
Powersim (http://www.powersim.com/)
Anylogic (http://www.anylogic.com/)
You may also try LibreOffice Draw or
Microsoft Visio
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Illustration of Causal Maps
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Impact of DDT on Malaria
Economy and population
Electrical energy system
Corruption system
Common pool resources system
Premarital Teenage Pregnancy & Motherhood
3
Impact of DDT on Malaria 1
Disease (Malaria)
S
S
DDT Use
B1
O
Mosquito
4
Impact of DDT on Malaria 2
DDT in Breast Milk
S
R2
S
Disease (Malaria)
S
SDDT Use
B1
O
Mosquito
5
Impact of DDT on Malaria 3
DDT in Breast Milk
S
R2
S
Disease (Malaria)
S
S
SDDT Use
B1
Mosquito O
# Rat
O
R3
S
DDT Accumulation in
Gecko (Lizard)
O
# Cat
6
http://butane.chem.uiuc.edu/pshapl
ey/Environmental/L37/1.html
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Impact of DDT on Malaria 5
DDT in Breast Milk
S
R2
S
Disease (Malaria)
S
S S
SDDT Use
B1
Mosquito O
# Rat
O
# Thatch Roof Eaten
and Destroyed
S
R3
S
DDT Accumulation in
Gecko (Lizard)
O
# Parasitic Wasp
O
# Cat
R5
R4
S
# Caterpillar
O
8
Impact of DDT on Malaria 6
• Loop 1 (Balancing): DDT Use→Mosquito
→Disease
• Loop 2 (Reinforcing): DDT Use→DDT in
Breast Milk→Disease
• Loop 3 (Reinforcing): DDT Use→DDT in
Gecko→Cat→Rat→Disease
• Loop 4 (Reinforcing): DDT Use→Wasp
→Caterpillar→Thatch Roof→Disease
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Economy and Population 1
• Sherwood (2002, pp.241-262)
Death Rate
S
S
R2
O
Population
S
B1
Deaths
S
Births
S
Birth Rate
10
Economy and Population 2
• Sherwood (2002, pp.241-262)
Disease
S
Death Rate
S
S
R2
O
Population
S
B1
Deaths
S
Births
S
Birth Rate
11
Economy and Population 3
• Sherwood (2002, pp.241-262)
Disease
S
Death Rate
S
S
Economic Activity
S
Desire for Wealth
S
R2
O
Population
S
B1
Deaths
S
Births
S
Birth Rate
12
Economy and Population 4
• Sherwood (2002, pp.241-262)
Pollution
S
B3
Resource Consumption
S
Disease
S
S
Death Rate
S
S
Economic Activity
S
Desire for Wealth
S
R2
O
Population
S
B1
Deaths
S
Births
S
Birth Rate
13
Economy and Population 5
• Sherwood (2002, pp.241-262)
Pollution
S
B3
Resource Capacity
Resource Consumption
O
S Competition for
Scarce Resources
S
S
Disease
S Famine
B5
B4
S
S
S
S Death Rate
War
S
S
Economic Activity
S
Desire for Wealth
S
R2
O
Population
S
B1
Deaths
S
Births
S
Birth Rate
14
Economy and Population 6
15
Economy and Population 7
16
Electrical Energy System
Demand
O
S
Price
O
S
Nuclear Energy
S
Supply
S
S
Other Energy
17
Corruption System
S
R3
Penalty
S
Amount of Bribe
S
R4
Profession & Ethics
O
R2
S
R5
O
O
Risk of Being Arrested
S
Bribery
O
O
B1
S
Effort of Investigation
Minimum Salary
18
Common Pool Resources
S
R1
My Egoistic Behavior
My Net Gain
S
S
Resource Limit
B3
S
S
Net Gain per
Individual
O
Collective Action
S
B4
Others' Egoistic
Behavior
S
R2
S
S
Others' Net Gain
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Premarital Teenage Pregnancy &
Motherhood
Teenage Abortion
O Dropout
S
S
O
O
Teenage Pregnancy
S
S
O
Education
Teenage
Mother
S
O
Teenagers' Sexual Risk
O
Career Opportunity
S
Socio-economic Status
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Opium Market System
Terrorism (Insecurity)
O
S
S
Governmental
Corruption
O
S
S
Trafficker (Smuggler)
O
O
O
O
Government Capacity
(Anti-terror/anti-drug)
S
Opium Price
S
O
S
Opium Traffic O
(Smuggle)
Social Development
(income, education)
S
Crop Cultivation
O
O
S
Opium Supply S
O
S
Puppy Cultivation
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References
• Anderson, Virginia, and Lauren Johnson. 1997.
Systems Thinking Basics: From Concepts to
Causal Loops. Waltham, MA: Pegasus
Communications.
• Sherwood, Dennis. 2002. Seeing the Forest for
the Trees: A Manager. London: Nicholas Brealey
Pub.
• Weick, Karl E. 1979. The Social Psychology of
Organizing. 2nd ed. Reading, MA: AddisonWesley Pub. Co.
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