1 Rockefeller College of Public Affairs and Policy University at Albany Tools for Systems Thinking and Modeling Dynamics: Graphs over time Structure:Causal-loop Diagrams Stocks and Flows

2 Rockefeller College of Public Affairs and Policy University at Albany Events and Decisions Patterns of Behavior System Structure Reactive Adaptive Generative Increasing leverage A Systems Perspective

3 Rockefeller College of Public Affairs and Policy University at Albany A systems view stands back just far enough to... Deliberately blur discrete events into patterns of behavior Deliberately move from a focus on individual decisions to a focus on policy structure “Distancing...”

4 Rockefeller College of Public Affairs and Policy University at Albany Events and Decisions Patterns of Behavior System Structure Reactive Adaptive Generative Increasing leverage The Systems Perspective

5 Rockefeller College of Public Affairs and Policy University at Albany Dynamics Define problems in terms of graphs over time. Graph important variables Graph historical data Graph anticipated dynamics Graph preferred dynamics Use these to focus systems thinking and modeling

6 Rockefeller College of Public Affairs and Policy University at Albany Unemployment (%)

7 Rockefeller College of Public Affairs and Policy University at Albany New York City Population,

8 Rockefeller College of Public Affairs and Policy University at Albany Unemployment & Welfare in Dutchess County, NY Unemployment Welfare roll

9 Rockefeller College of Public Affairs and Policy University at Albany Per Capita Residential Energy Use (USA Today 3/23/09, citing Census Bureau and U.S. Energy Information Administration)

10 Rockefeller College of Public Affairs and Policy University at Albany Here’s where we went wrong... Strive for Insights

11 Rockefeller College of Public Affairs and Policy University at Albany Events and Decisions Patterns of Behavior System Structure Reactive Adaptive Generative Increasing leverage The Systems Perspective

12 Rockefeller College of Public Affairs and Policy University at Albany Accumulations (populations, resources…) Causal structure: “feedback” loops Delays Perceptions (a kind of accumulation) Pressures Affects, emotions, (ir)rationalities Policies governing decisions Systems Structure

13 Rockefeller College of Public Affairs and Policy University at Albany Causal Loop Diagrams Causal mapping is a powerful tool for representing structure in complex systems. Arrows indicate causal influence.

14 Rockefeller College of Public Affairs and Policy University at Albany Polarities of Causal Links Positive and negative signs show the direction of causality: – + + – + – +... “direct” relation – …“inverse” relation

15 Rockefeller College of Public Affairs and Policy University at Albany Definitions of Link Polarities All words phrases are expressed as quantities that have a clear sense of increase or decrease. No verbs — the action is in the arrows. A adds to B, or ∆A leads to ∆B in the same direction C subtracts from D, or ∆C leads to ∆D in the opposite direction

16 Rockefeller College of Public Affairs and Policy University at Albany Simple test for link polarity An increase in A makes B higher than it would have been without the change. An increase in C makes D lower than it would have been without the change.

17 Rockefeller College of Public Affairs and Policy University at Albany Examples “Ceteris paribus”... All other influences held constant as we assign polarities. Emigration subtracts from population: An increase in emigration means less (a decrease means more) than we’d have without the change More lawyers mean more litigation; fewer lawyers, less litigation + –

18 Rockefeller College of Public Affairs and Policy University at Albany Exercises d

19 Rockefeller College of Public Affairs and Policy University at Albany Feedback Loops A feedback loop exists when decisions change the state of the system, changing the conditions and information that influence future decisions.

20 Rockefeller College of Public Affairs and Policy University at Albany The Joy of Feedback

21 Rockefeller College of Public Affairs and Policy University at Albany The Joy of Feedback

22 Rockefeller College of Public Affairs and Policy University at Albany No — it’s more like the life cycle of the famous scientist

23 Rockefeller College of Public Affairs and Policy University at Albany Examples of Feedback Loops

24 Rockefeller College of Public Affairs and Policy University at Albany Two kinds of feedback loops Reinforcing loops Growth producing Destabilizing Accelerating Positive: an even number of –’s Symbolized by Balancing loops Counteracting Goal seeking Stabilizing Negative: an odd number of –’s Symbolized by

25 Rockefeller College of Public Affairs and Policy University at Albany Examples of Reinforcing Loops – –

26 Rockefeller College of Public Affairs and Policy University at Albany 26 Isolate and Identify Link Polarity

27 Rockefeller College of Public Affairs and Policy University at Albany 27 Isolate and Identify Link Polarity (Always trace an Increase) +

28 Rockefeller College of Public Affairs and Policy University at Albany 28 Isolate and Identify Link Polarity (Always trace an Increase) +

29 Rockefeller College of Public Affairs and Policy University at Albany 29 Isolate and Identify Link Polarity (Always trace an Increase) –

30 Rockefeller College of Public Affairs and Policy University at Albany 30 Isolate and Identify Link Polarity (Always trace an Increase) –

31 Rockefeller College of Public Affairs and Policy University at Albany 31 Isolate and Identify Link Polarity (Always trace an Increase) +

32 Rockefeller College of Public Affairs and Policy University at Albany 32 Completed Loop (Now tell the story) + – – + + (R)

33 Rockefeller College of Public Affairs and Policy University at Albany Typical Reinforcing Loop Behaviors 20,000 15,000 10,000 5, ,000 9,000 8,000 7,000 6, Population and Births Loop Businesses and Taxes Loop

34 Rockefeller College of Public Affairs and Policy University at Albany World Population (billions)

35 Rockefeller College of Public Affairs and Policy University at Albany Self-reinforcing processes in world population growth

36 Rockefeller College of Public Affairs and Policy University at Albany Reinforcing Feedback in the Newspaper

37 Rockefeller College of Public Affairs and Policy University at Albany Reinforcing Feedback in the Newspaper

38 Rockefeller College of Public Affairs and Policy University at Albany Reinforcing Feedback in the Newspaper Garfield’s happiness Jon’s suspicion (R)

39 Rockefeller College of Public Affairs and Policy University at Albany Examples of Balancing or Counteracting Loops + – + + – – +

40 Rockefeller College of Public Affairs and Policy University at Albany Typical Counteracting Loop Behaviors Filling a Glass 10,000 7,500 5,000 2, Population and emigration Predator-prey interactions

41 Rockefeller College of Public Affairs and Policy University at Albany Tips for Determining Link and Loop Polarities For each link, determine the effect of an increase in the variable at the tail of the arrow: If the variable at the head increases, assign a plus. If the variable at the head decreases, assign a minus. For each loop, count the number of negative signs: An even number of negative links is a reinforcing (R) loop. An odd number of negative links is a balancing (B) loop. Most important: For each loop, tell a self-reinforcing or balancing/counteracting story, and check that the story matches the loop polarity.

42 Rockefeller College of Public Affairs and Policy University at Albany More Serious Example from the Newspaper: Recall the graph of per capita energy use

43 Rockefeller College of Public Affairs and Policy University at Albany Presentation Dynamics Clarifying questions Audience understanding Clarity of presentation

44 Rockefeller College of Public Affairs and Policy University at Albany Presentation Dynamics - Which loop dominates?

45 Rockefeller College of Public Affairs and Policy University at Albany Stocks and Flows Stocks are accumulations. Stocks are increased by inflows and decreased by outflows. When a link means “add” or “subtract” we have a stock-and- flow structure. Example: Inventory

46 Rockefeller College of Public Affairs and Policy University at Albany Stock and Flow Diagramming Conventions

47 Rockefeller College of Public Affairs and Policy University at Albany A Stock and Flow Example Explicit stocks and flows: The corresponding causal-loop diagram:

48 Rockefeller College of Public Affairs and Policy University at Albany Human Activity, CO2, and Global Temperature Thought experiment:

49 Rockefeller College of Public Affairs and Policy University at Albany Structure and Dynamics of Terrorist Cells New recruits Terrorist group Losses Terrorist actions Suppression activities Zeal Peripheral support Funding Martyrs to the cause (R) (B) (R) (B) (R)

50 Rockefeller College of Public Affairs and Policy University at Albany Balancing Loops in Tobacco Prevalence

51 Rockefeller College of Public Affairs and Policy University at Albany Balancing Loops in Tobacco Prevalence

52 Rockefeller College of Public Affairs and Policy University at Albany Loops and Constituencies

53 Rockefeller College of Public Affairs and Policy University at Albany There are a lot …

54 Rockefeller College of Public Affairs and Policy University at Albany Policy Resistance of Complex Systems

55 Rockefeller College of Public Affairs and Policy University at Albany Policy Resistance of Complex Systems

56 Rockefeller College of Public Affairs and Policy University at Albany Policy Resistance of Complex Systems

57 Rockefeller College of Public Affairs and Policy University at Albany Policy Resistance in Complex Systems