Models Don’t Make Predictions, People Do!
Models Don’t Make Predictions, People Do! Models and I go back a long way. I created relatively simple spreadsheet models by hand for 6 years at Arthur Andersen & Co. These were done on 14-column paper with a box of Ticonderoga #3 pencils and a Pink Pearl eraser....
Simulation During Times of Crisis
Simulation During Times of Crisis Scientists and researchers spend a long time crafting mathematical models that simulate multiple phenomena occurring in organizations and societies. Those models use varied methodologies based on either proven theories or envisioned...
Renewing my membership in the System Dynamics Society
Renewing my membership in the System Dynamics Society In 2009, at the International Conference of the System Dynamics Society, President Erling Moxnes started his Presidential address by saying, ‘”Groucho Marx said “I refuse to be a member of any club that would have...
Why we do not always simulate
Why we do not always simulate By Vincent de Gooyert, Inge Bleijenbergh, Hubert Korzilius, Brigit Fokkinga, Monic Lansu, Stephan Raaijmakers, Etiënne Rouwette, Merel van der Wal With great interest we have been following and participating in discussions on what ‘good’...
What scientific rigor can and cannot buy us
What scientific rigor can and cannot buy us Many words have been written about how System Dynamics modeling should be scientific and rigorous. An initial dynamic hypothesis will always have shortcomings, and these can be revealed by model testing. We must go through...
How to right-size your model
How to right-size your model I once developed a relatively compact System Dynamics model to help a major chemical company restructure their plastics business. The model was well received by senior management but was not considered granular enough for accurately...
Group model building: a dialogue
Group model building: a dialogue In the late 1980s, academics on both sides of the Atlantic started to develop structured techniques for eliciting knowledge from expert and client groups as part of System Dynamics modeling. The goal was to democratize or “open up” the...
The endogenous perspective: a friendly amendment
The endogenous perspective: a friendly amendment I have developed lots of System Dynamics models over the years for both private and public organizations. My models have all been built to answer strategic questions for which there was no single obvious answer, due to...
Let’s consider policy feasibility
Let’s consider policy feasibility I was once consulted by a semiconductor equipment maker who wanted to reduce their service maintenance costs. The client team offered a variety of ideas, some of which were workforce-related and could be implemented fairly rapidly,...
Six Reasons to Apply System Dynamics Modeling in Medical Research
Six Reasons to Apply System Dynamics Modeling in Medical Research (Moderator’s Note: After several recent conversations with Ken about different dimensions of SD in medical research, and as a follow-up to his recent post, I asked him to provide a short list of the top...