Web of wonder: Developing models [Systems thinking & modelling series]

This is part 7 of a series of articles featuring the book Beyond Connecting the Dots, Modeling for Meaningful Results.

Construction process

While there are endless reasons for constructing a model, it all boils down to learning and understanding. The “Model Construction Process” model is intended to present the essence of all model development.

This model should reinforce the idea that models can cut through all the confusion and present the essence of a set of interactions to provide a consistent understanding. Can you see this essence in the models that have been developed to this point?

The essence of AND?

Developing models is actually the easy part. What you should strive for is developing models that advance your understanding and allow you to surface insights to better address situations around you. Evolving a model to surface insights can be a relatively straightforward and simple process, which we hope is conveyed by the following “The Essence of AND?” model.

The process presented can be used with Rich Pictures or Causal Loop Diagrams as well as Stock & Flow Simulations. When developing Stock & Flow Simulations you also have to be certain that the model runs and produces a meaningful result. When developing a simulation you should never be more than a couple of clicks away from a working model. You’ll better understand this advice through experience. After you’ve made a substantial number of changes to a working model, it then didn’t run, and you’ve spent hours trying to figure out how you broke it you’ll see what we mean. Do yourself a favor: think about what the changes should produce, run after every change, and verify that the model produces what you expected. It only takes a minute. And when the simulation doesn’t produce what you expect, it’s not a problem, it’s an opportunity for learning.

Modelling guidelines

There are a number of guidelines, or rules of thumb, that you will find helpful when developing a model. These are presented in the following “Modelling Guidelines” model. The idea is to ensure that the model serves the purpose for which you started building it. Some of these guidelines are only relevant for Stock & Flow simulations; these should be quite obvious.

Remember, model development and associated understanding is an iterative process. It’s almost impossible to create all the pieces as they should be the first time around. Do a little, learn a little, and repeat.

Next edition: Web of wonder: Summary.

Article sources: Beyond Connecting the Dots, Insight Maker. Reproduced by permission.

Header image source: Beyond Connecting the Dots.