09/02/2008-10/22/2008
Topic: Production and Consumption, Uncertainty
Professor Jan Werner's page: http://www.econ.umn.edu/~jwerner/teaching.htm
Announcement:
09/06: The Midterm will be on Thursday, Sep 25th. Recitation Time. (tentatively)
09/28: The Midterm Answer Key is posted.
F.A.Q:
09/06:
Q: (For HW1, Q1): "Can I use the theorem "if f is concave and the constraint function is concave...then FOC will be sufficient..."
A: I think you are refering the theorem 7.16 or 8.13 in Sundaram's book(see the reference in the course syllabus). It might be promising to get the solution by this theorem(rather than using my hint) and you don't have to prove the theorem. But you should show me step-by-step: why are the functions concave(or quasi-concave)?Also, Notice that Max{(-y1)^0.5-2, 0} is not a continuously differentiable function on the whole negative real line! So you might want to carefully define: what's domain of y1, y2 or both, and what's the constraint function. Aslo, notice that the profit should not be negative since 0 is always in Y.
When you are citing a theorem, please state the theorem clearly and tell me where it is from.
09/12
"May I assume that the supply function is continuous when I do Q2 HW2?"
Well, you can add assumptions if you cannot find a better solution. It's better than nothing. I can hardly say it is allowed or disallowed. How will I grade it? It depends. If the Question is too hard(or even a wrong question), then it should be OK if you make additional assumptions. But if I, or some others do find a solution without additional solution, I'll take off some points, depending on how elegent your solution is. Notice that in Micro Theory most of the questions are clearly and carefully stated. So most of the time you don't need to add assumptions (Unlike Macro) although I cannot exclude some counterexamples.
In particular, for Q2 HW2, I don't think you need to add this assumption. But again, it is better than nothing if you can slove it with this assumption.
"Could you give me some hint..."
Depends on time. If the HW is posted on Thursday and you ask me for hint on Friday's happy hour, surely I cannot tell you. Because you should think of it seriously over the weekend. If you still have no clue after a weekend, I might be able to give you some hint if people ask me the same question(It indicates the question is indeed difficult) in the office hour, but not a lot for the reason of fairness .
But I'm glad to discuss the lecture notes, graded homework, or any other difficulties, etc. Plus, be aware that I cannot type complicated math formulars in emails.
|