Good
Professor Yan is not bad. Group project will be a big part of your grade. Also, a lot of homework is online that is a bit boring, but it's very easy. His multiple choice exams were timed. Overall, it's a pretty good class.
Poor
Professor Yan is not the worst, he's just not great. His individual assignment has very vague directions on it. Also, he only graded a few things. The group project and individual assignments make up most of those. I'd take him again, but I suggest you take someone else if possible.