This is a horrible class. The only reason why the department wants to keep him, I guess, is because he is actually very organized as a teacher.
This class is about report-writing, not about doing experiments.
He's alright at explaining concepts.
There's not much to learn in this class - except some formatting tips.
I doubt that Grasel or his TAs had much of an understanding about statistics -- they just blindly insisted that we provide statistical context to our data.
It was hard to know what Grasel expected from you in this class.
Expects a bunchload of writing, annoying (problematically compulsive) attention to detail, and just plain boring -- that's how I would describe Grasel. You don't even need to be smart to do well in this class - just annoyingly hardworking - like a bee.
The department actually likes him a lot -- from their perspective, Grasel is a good professor - does everything on time , so on and so forth.
But they need to find someone new. These low ratings aren't a joke.
Grasel made me put my liking for ChemE in perspective, as I was about to enter my 4th year.
At some level, I hope Grasel reads this, and considers quitting the department given how much we hate his teaching style.

To be completely objective: by far the worst class I have taken so far at UCLA. It's entirely due to Timothy Grasel's abhorrent personality.

This class has weekly write ups, oral presentations, data summaries etc. What makes the clas terrible is the professor. I once emailed him for help and he then proceeded to ignore my email for two days, then addressed it front of the entire class. It was private information. And I do not believe this professor should be teaching.

It is known that he had a problem with racism in previous classes (not towards me though).

The class itself is poorly organized. If you do much as make one mistake in your lab reports, your grade suffers immensely. So be careful with grammar, graphs, and overall organization of your report. Follow his ridiculously long style-guide and you'll be fine. Overall I don't recommend this class because of who teaches it, but what choose do you have.

For the record I'm very happy with my grade, but suffering through Timothy Grasel and his horrendous grading schemes was just not worth it.

Pros: Actually learn a few useful things about statistics. You also learn a decent amount about some cool chemical engineering stuff.

Cons: Easily one of the most difficult classes I've ever taken at UCLA in terms of detail, workload, and grading. He is fair, I'll give him that. But the sheer amount of work for this class is unbelievable - although the reports are only 5 pages, and the presentation a max of 10 slides, every single word choice must be absolutely flawless to get anything above a B. Tim Grasel is an insanely detail oriented grader who loves nothing more than to mark you off for formatting mistakes which you forgot somewhere in his 25pg Style Guide (just for this class), or maybe just because he was feeling like it and couldn't find anything reasonable to grade on. The facets of this class are numerous - lab notebooks, punctuality, oral presentations, homeworks, readings (hundreds of pages on statistics), design of experiments, designing your own final project (if it doesn't work you'll get a bad grade), quizzes, investigation reports, feedback forms, proposal, SO MUCH STUFF, and something is due every week..

Your grade is very dependent upon how much time you put into this project. For an A, you should be spending 20 hours/week doing stuff for just this class PER WEEK on OFF WEEKS and easily twice that on weeks where stuff is due.

Lectures are absolute garbage. Don't go. Even after attending you will not be able to do the homework based on those alone.

My rating of this class is like 2/10, and only that because you actually do learn some useful things. Grasel himself and the course organization gets a 0/10. This class is your worst nightmare; if you're terrified of this class after reading this, GOOD. YOU SHOULD BE.