Systems Thinking Introduction - a quick overview for Software Practitioners

Systems Thinking Intro, prepared for Virtual Domain-Driven Design meetup

1. Systems Thinking Introduction Presented by Lorraine Steyn @lor_krs lorraine-steyn Prepared for Virtual Domain Driven Design Meetup

2. Systems Thinking is a discipline for seeing wholes rather than parts, patterns of change rather than static snapshots, for understanding the subtle interconnectedness that gives living systems their unique character. Peter Senge

3. ELEMENTS Easy to identify parts of a system CONNECTIONS Physical flows, information flows PURPOSE Observe how the system behaves over time

4. Purpose of school? Are we preparing our children for the world, or just teaching them to take tests?

5. Feedback Loops Systems echo chamber where outputs influence inputs Reinforcing: amplify a change Balancing: counteract a change to stabilize the system

6. Balancing Feedback Loops

7. Reinforcing Feedback Loops

8. Causal Loop Diagrams Hunger Food - + B

9. Savings Acc Interest + + R Money Causal Loop Diagrams

10. Causal Loop Diagrams Fishing Fish Population - - R

11. Boundaries

12. Rise of complexity – Wicked Problems Socio-technical problems New scale and scope Highly interconnected and interdependent Accelerating pace of change

13. What justification can there be for assuming that we do not know enough to construct models of social systems but believe we do know enough to directly redesign social systems by passing laws and starting new programs? “ ” Jay W Forrester

14. Stocks and Flows 1. Stocks Nouns / Accumulations – wolves, forest, happiness Measurable – population level, forest coverage

15. Stocks and Flows 2. Flows Verbs / Actions – births, construction, usage Measurable – birth rate per year, daily rainfall, website visits per month A Stock needs a flow to change

16. Reinforcing / Amplifying Loops Push the system in the same direction as the initial action Balancing / Stabilizing Loops Push against the initial movement Stocks can influence loops (”you need money to make money”) 3. Feedback Loops Stocks and Flows

17. 4. Variables influence flows Quantifiable Example: Animal Birth Rate per year is influenced by predators, environment, survival rate Stocks and Flows

18. Example Stock and Flow Diagram Task workflow for a procrastinator Open Tasks Closed Tasks Completion Rate Effort Productivity Schedule Pressure Remaining Time Procrastination Workflow

19. Use standard variables – if money, stick to money not units Stocks need an initial value Flows can be plotted between ranges Modelling Tools: Stella, Vensim , VisualParadigm , Excel Measurements

20. Example Stock and Flow Diagram Task workflow for a procrastinator Open Tasks Closed Tasks Completion Rate Effort Productivity Schedule Pressure Remaining Time Procrastination Workflow 40 1/day Raises by 2 per day as we approach the deadline

21. Can we store it? What creates the stock? What depletes it? Thinking about Stocks

22. Code as a Stock Can we store it? Working Code Business value Is understood by Team Can be modified

23. Code Value is tied to Team Knowledge

24. What lies beneath?

25. Microscope to Telescope

26. Policy Resistance “As the world changes ever faster, thoughtful leaders increasingly recognize that we are not only failing to solve the persistent problems we face, but are in fact causing them” John D. Sterman - All models are wrong: reflections on becoming a systems scientist

27. Solving vs Dissolving Ask “What is possible” not “What is wrong” Find new ways of doing things What are the leverage points (inflows and outflows) Innovation is about change in socio-technical systems

28. Imagine, Research, Act Creating New Solutions

29. Systems always behave exactly as they are designed, just not always as they are intended.

30. Comments and Feedback @lor_krs

31. Donella Meadows – Thinking in Systems Peter Senge – The Fifth Discipline Jay W Forrester – Counterintuitive Behavior of Social Systems John D. Sterman - All models are wrong SI Institute – https://www.systemsinnovation.network/ posts/guides-systems-innovation-guide posts/guides-actor-mapping https://thesystemsthinker.com/ step-by-step-stocks-and-flows-converting-from-causal-loop-diagrams/ References