Non-rational Choice Theory

Last week I criticized Dr. Satoshi Kanazawa for his approach to explaining voting in terms of rational choice theory. This week, I would like to agree with Kanazawa, people really are irrational. I thought of this especially because of a piece by David Warren about how so many homeless people are mentally ill. The hard part about being crazy is that you need to not be crazy in order to stay on your meds. Granted, the meds are supposed to help with that, but it is never enough.

But, the truth is, even sane people don't really do what their doctors tell them. Patient compliance is one of the hardest things for doctors to monitor, because everyone says they'll do whatever it is, and some percentage of people don't. I don't know whether C is correlated with this, but non-compliance is pretty widespread. Even when the benefit of compliance is obvious and the cost is equally obvious, a substantial proportion of totally normal people won't comply.

How do you model a bad decision?