One request was this:
The role and future of intelligent agent modeling in economics.
Call me a stuck up sticky bit but I don’t see a bright future for this technique. We already have, and have had, computable general (and partial) equilibrium models for decades. In those models you try to estimate the parameters from empirical data. The models rarely impress me but there are plenty of situations, such as estimating the effects of changes in the tax code, where we don’t have anything better. And so those models survive, and will continue to survive.
What’s the important innovation behind intelligent agent modeling? To introduce lots of arbitrary assumptions about behavior? Greater realism? Complexity? Considerations of computability? Learning? We already have enough "existence theorems" as to what is possible in models, namely just about everything. The CGE models already have the problem of oversensitivity to the initial assumptions; in part they work because we use our intuition to calibrate the parameters and to throw out implausible results. We’re going to have to do the same with the intelligent agent models and the fact that those models "sound more real" is not actually a significant benefit.
What can be done will be done and so people will build intelligent models for at least the next twenty years. But it’s hard for me to see them changing anyone’s mind about any major outstanding issue in economics. What comes out will be a function of what goes in. In contrast, regressions and simple models have in many cases changed people’s minds.
Sometimes a theory model tells you there are many many equilibria, as in much of game theory.
I believe that result is to be taken seriously and we should conclude
that many different things can happen in that situation. I am
suspicious of trying to solve for the correct or most likely
equilibrium by introducing many more specific assumptions.
In my possibly overdogmatic view, economics is most useful when its models are relatively simple and intuitive. We’ve run out of new models which are simple and intuitive. So the theory game is over. The standard, old data sets have been data mined to death. We’re now on to the "can you build/create your own data set?" game. That game can and will last for a long time; in some ways it will favor go-getter extroverts just as the theory game favored introverts.
I don’t yet see that there is a new game in town. My preferred reform of economics involves more history and anthropology, I might add.
Addendum: Bob Murphy asks:
It may be apocryphal for all I know, but I once read that the editor
of the journal to whom Einstein sent his paper on special relativity
put it down and realized that physics would never be the same (or
something like that).
Is something like that even possible in economics? What would it be like? Say, the Lucas critique times 10?
The answer is no, in my view this is not possible, for reasons given above.