better to study off the textbook

Prof sucked so bad, he made easy trivial material confusing. Great and fun material. It should be easy (u can see Voss' reviews).
This class should be super easy, but the prof not only sucks at teaching, he makes it even more confusing. You are definitely better off self learning (and not going to lecture). 75% of the class never showed up to lecture
The book is great, explains things well. His slides are straight from the book (and i think he just took Voss' slides). Nice class material, nice workload, pretty easy, prof cannot teach for the love of god.
We also ended up skipping one of the biggest prominent models - Black Scholes, due to his organization and clarity.

Math 170S with Gurdogan is a strange class. First of, be an expert in 170E. He loves use Binomial, Exponential, Gamma, Beta, and Chi Squared distributions. A lot of profs skip some of the later stuff, but he will assume you are experts on them for the test. He also gives absolutely no practice, especially for Bayesian Statistics (one of the hardest topics), so maybe ask GPT to make some hard questions involving that. The second half of the class is almost entirely plug and chug, and the MT was significantly harder than the final because of that. He also goes into many tangents on proofs which he never tests on and lecture isn't very useful compared to slides.

I took the summer session so the content was accelerated but overall was still very manageable. No textbook is really needed because the slides copy-paste the most essential information and the z, t, and chi square tables are all provided on exams.

I will say that this professor struggles to explain concepts clearly, and focuses a bit more on proving theorems (not tested) than actual application. I think the best strategy to get a good grade is to review the lecture slides then use the homeworks to test your understanding. The exams are the same difficulty level as the homeworks and there are few curveball questions. I'm pretty sure he curves depending on the grade distribution.

Concepts from 170E are pretty much the foundation of this course so brush up on that before starting, as he will expect you to know poisson, gamma, beta, and chi square distributions, their expected values and their pdfs are fair game.

Professor Gurdogan is an extremely kind person who clearly cares deeply about his students' understanding, but unfortunately he was not the best professor for this class. Oftentimes his lectures and proofs did not shed great understanding of the material, and learning from the textbook was more efficient than lecture. The class is not very hard though, and I should have done better but I did quite well on the midterm and neglected to study enough for the final.