As discussed above the process of building models requires the generation of an hypothesis about what kind of structure might be responsible for the behavior in the reference mode. This can be quite difficult, but it does become easier as you gain experience with model building. One reason it becomes easier is that you will gain experience with different structures and the behavior they generate. Studying the simplest and most fundamental patterns of behavior and the simplest structure that can generate the behavior is a useful way to get started on gaining this experience.
In the following sections we percent growth, decay, adjustment and oscillation and some simple structures that generate them. The models are presented in causal loop form to emphasize feedback which is an essential part of generating a dynamic hypothesis.
