For the rest of the semester, we'll spend the morning sessions discussing in detail each of the steps in model-building. We'll do one step each session, and you'll participate in the discussion, drawing on your group projects as main sources of examples. For the first couple sessions, I expect some groups won't even have reached the day's step yet. In later sessions, groups will have moved past the step weeks earlier. That's fine: in the earlier sessions, the discussions will provide direction and be an opportunity for you all to think aloud, bounce ideas off the group. In the later sessions, you'll have the experience of thinking through the questions, and you may also have the benefit of seeing some of the consequences of your choices.
Today we'll discuss the very first step, defining the phenomenon. What are you trying to model? How do you describe it -- to what level of phenomenological detail, to what level of mechanistic detail? and why do we have to be so careful about defining the phenomenon anyway? Nature doesn't have defined, discrete phenomena, so aren't we just dissecting the world artificially into arbitrary pieces?
