Do not take this class with this professor unless you want to suffer. The material itself should not be difficult, but Hahn makes his tests ridiculously time constrained and more difficult than any preparation materials. The course grading is 40% midterm and 60% final, so prepare to be blindsided by the midterm and then have only 1 opportunity to improve your score at the final. Questions are harder than the homework problems or the problems done in class, so there is no way to adequately prepare for the exam questions, especially given the time constraint of around 2 minutes per question. Topics that are emphasized in class/homework barely show up on the exam, while topics that are brushed over show up repeatedly. To make things worse, "None of the above" is the answer A LOT, so it plays mind games even for those who do calculate the correct answer. Also, Hahn does not allow you to see your midterm exam AT ALL to review it. You only receive your scantron back and never get to see the actual questions, which makes it impossible for you to learn from your mistakes.

EXTREMELY hard exams. midterm is 30 questions in one hour. you're supposed to spend less than two minutes per question but he made that impossible. he doesn't give out his past exams, doesn't do review sessions, and doesn't give you practice questions. he'll assign a small amount of exercises from the textbook and tell you that the exam questions will be like those homework questions. lol DO NOT FALL FOR THAT. midterm problems were SO difficult and like nothing we had seen in lecture or in homework before. the average and the median on the midterm was a D!! the final was easier but impossible to finish on time.
also, no cheat sheet allowed and only a simple canon calculator is allowed-- which easily messes up your calculations, wastes your time, and lowers your exam scores.
i stopped going to lecture once i found out that his lecture notes are more thorough and helpful than he is in person. He also does this weird thing where he locks you into the exam room until all of the TAs count the scantrons and exams and make sure the numbers match up. he held us in for like 15 mins trying to figure out who cheated or who came to do the exam 'for fun', only to find out that the TAs had miscounted...

Overall, I thought Professor Hahn was an effective lecturer. There is no homework; the only grades are a midterm and final, so it is up to you to hold yourself accountable and stay up to date with the material. If you put things off, it is easy to be overwhelmed, and you will have a hard time catching up. Timing on the exams was quite tough, but most people have this issue and the class is curved anyways. For anyone who is interested in econometrics/statistics, I’d highly recommend taking Econ 41 with Hahn. He gives you an in depth look at the material with proofs.

Professor Hahn is not that bad. I appreciated how articulate and clear Hahn was in explaining concepts. Like seriously, this guy is my type of lecturer: perfectly clear and articulate. His tests are kind of challenging but nothing out of the norm. To do well in this class, you should know how and when to apply the calculus formulas he provides on his tests, and you should know definitions very well. Seriously, the 'tricky' questions almost always just require you to manipulate a bit or have knowledge of exact definitions which isn't hard if you study them with flash cards or something. Overall, a good lecturer and very underrated imo.

3 years at UCLA and Hahn is the absolute worst teacher I have ever taken. He allocates time to specific subjects terribly. He will spend hours on the easiest subjects in the class but then glance over the hardest parts and just says "you should know this already" and laugh. He was insanely anal about exams to the point where he took away the "cheat sheet" that you used to be able to use. He keeps you locked in the classroom until they confirm that everyone took the test which can be around 15 minutes after the exam is over. Also prepare to hear "the tests are simply a reflection of the homework" HAHAHAHA the most certainly are NOT. His exams (though multiple choice) are nothing like the homework. Averages are around 60%. Whoever guesses better wins. Good luck lol.

Hahn is very difficult. Tests are time constrained and as of 2018, the calculator is limited to standard 4 functions + root. No note sheet. 62 Qs, 120 min final. Midterm is 31Q, 75 min. Tests include proof-based questions that rely on exemplary knowledge of content.

Explanations are far too complicated for such an elementary class. Grading is 40% midterm and 60% final. Hahn is clearly incredibly intelligent, but perhaps too qualified to teach this class. No attendance, lecture notes online, HW.

Perhaps a good choice if you have a truly excellent grasp of the content. Prior intro stats classes (AP, community college) don't really prepare you for it.

I suspect that all glaringly positive reviews are deceptive econ majors trying to get you in the class to bring the curve down.

Absolutely fucking awful exams. Professor Hahn is extremely anal about his test taking, and the exams themselves are more a test of time than of the material. some questions are absurdly difficult to do with only a pencil and a canon LS-100TS calculator. cheat sheets are no longer allowed, despite what previous reviews say. terrible professor.

Good class overall. Need textbook for HWs and exams. Selling book for $80 (new costs $120). Email: *************

Fair professor.
Sell the textbook. Text **********

Hahn is pretty good. His strictness about his grading scale and test taking methods is a bit bizarre though. Was at the average on the first midterm, and got top 5 on the final, ended up with an A. I attended class the first half of the quarter, and stopped going and never went to discussion and just did the HW problems until I was able to do them without thinking. You need to be able to test quickly, but I never felt like I was in a time crunch. The notes he provides are very thorough, and pretty much have everything you need to know.

Definitely the best professor I've had in the department.