Reviews of professor Li Duan

Rating: 5.0/5, difficulty: 3.0/5
Amazing! Great lecturer and very knowledgeable. Easy to communicate with in and out of class. The topics were difficult but he made them approachable and encouraged discussion in class. HW were challenging but he's very helpful and grades leniently. Exams open notes. Easy A, but you will still take out a lot from the class.

Rating: 5.0/5, difficulty: 2.0/5
Dr. Duan is lowkey hilarious, very knowledgeable/intelligent and approachable. His lectures are usually pretty good and he often mentions interesting/fun applications of the techniques. Homework was slightly challenging, but really not bad and exams were not hard. Content can be challenging and interesting, but Duan explains well and exams are fair

Rating: 5.0/5, difficulty: 1.0/5
Short non-mandatory lectures and it's easy to catch up using the slides. Only 4 homework assignments and 3 non-cumulative exams the entire semester, and for each one he told us what to study (and you could bring a notes sheet). High averages for all exams. Would've liked more examples and practice, but I still recommend this professor and class.

Rating: 2.0/5, difficulty: 3.0/5
The class isn't difficult if you have a strong stats background. However, Duan makes it more complicated than it has to be. He often says the wrong thing and has to go back and correct himself or completely redo a problem. His handwriting can also be hard to read at times. His tests and grading are very fair.