Multi-use Models

Models are like kitchen utensils. You need a variety of them, and you should know when and how to use them. They should be useful for more than a single task. I recently started exploring the first explicit model I learned years ago.

The Cyberntic Model

One of my more interesting college classes was feedback control. The class was based on differential equations, Laplace transforms, and a single model that looked like this:

This model is the basis for most of the process control in the world. Basically the setpoint gets compared to the actual value. The error value goes to a controller, that then takes a corrective action. If the temperature is to hot, the corrective action might be to reduce the heat in the temperature jacket. After a while, things cool down. All processes have a time lag between the corrective action and when the change arrives at the output. I “borrowed” the “delay symbol” from Causal Loop Diagramming to show this. If it gets too cool, the controller will change the action and add more heat.

I didn’t realize at the time how powerful and versatile this diagram is.

Personal Problem Solving

With just a few word changes, the model can be used to describe how people can solve their problems.

A problem exists when a difference exists between what we want, and what we have. We can solve the problem by changing our actions, and seeing if the world at large responds with results that are closer to what we desire.

I’m trying to lose a few pounds. I can change what I eat (calories, fat, carbs, pick your favoite fad diet). I can change how often I exercise. If I continue with these changes, eventually I should lose the weight.

Project Management

Change a couple of more words, and now we have a project management tool.

 

In this drawing, I’ve used a dash line connection between the manager (in this case synonymous with leader) and the team. I made this distinction since managers don’t have a direct linkage to the team. Managers can ask, cajole, threaten, and perhaps fire team members who don’t perform the tasks they’ve been asked to do. But the team member always has a choice.

One Size Does Not Fit All

Like kitchen utensils, you also need to know a model’s limits. I don’t grab a chef’s knife when I want to mix butter with sugar and I don’t draw diagrams of effects when I’m dealing with personality differences. As useful as the Cybernetic Model is, there are situations where it doesn’t apply.

Got a favorite model you’d like to share? Send me an email.