Building models (info or economic) in your spare time

I enjoyed reading Hal Varian's paper How to Build an Economic Model in Your Spare Time. It succinctly describes how to build a theoretical model for how a system may work, from getting the idea, to testing it out, to improving it. It requires you to have a little ambition and a little less ego. At the end, he summarizes his major points, and it strikes me that this is also a good way for any student or academician in any discipline to grow intellectually and think bigger thoughts.

  • Look for ideas in the world, not in journals.
  • First make your model as simple as possible, then generalize it.
  • Look at the literature later, not sooner.
  • Model your paper after your seminar. (Varian recommends leading a seminar on your model, which forces you to get your ideas in shape so your presentation both educates and entertains your audience.)
  • Stop when you've made your point.

Of course, he goes into greater detail on these and other points, but I really liked the first one: read magazines to get an idea of the ideas and problems that are in the air. That appeals to my pragmatic side.

And since I'm a total software geek, I also enjoyed reading how he uses his computer to write his papers. At the time of the writing (the last update was in 1997) he used UNIX, kept a notes.txt file to contain ideas, thoughts, an outline, and in general used this file similarly to Mark Forster's idea of continuous revision. Only after he's collected ideas for weeks and months does he move to writing a first draft of the paper or chapter. He also uses UNIX's rcs for a revision control system.

Insofar as his idea of writing notes from audience or seminar Q&As, I'd suggest you use either a tape recorder or get a volunteer to write the questions and comments down for you.