18.600  Probability & Random Variables

okay, two more things

1. I will be teaching 18.677 next semester, so if you or anyone you know wants to come to some "Geometric Probability" lectures you will be very welcome. I will be covering a lot of what I consider the most beautiful stories involving the combination of randomness and some sort of geometric structure (random graphs, random trees, random curves, random surfaces, random connections, etc.)

It might not be easy to take 18.677 for credit right after 18.600 (it would at the least require a fair amount of extra reading outside of class on 18.675 material, etc., and the class will be research focused) but participation is welcome regardless.

2. If anyone wants to stop by on registration day or during my 18.677 office hours next semester (to say hello, to look at your final exam, to ask a math questino, etc.) you are quite welcome to do that.

Cheers,

Scott

Announced on 18 December 2019  10:50  a.m. by Scott Roger Sheffield

final farewell

Dear Class,

I have approved the grades for your final exam (visible now on Stellar) and your overall grades have been submitted to the department/registrar. I am not sure how long the administrative side will take, but I hope the grades will be visible today at some point.

The class average on the final exam was 73, which I think is really excellent considering the conceptual difficulty level. This was by no means a trivial exam.

As a matter of policy, I do not make post-final-exam grade changes in response to email requests or final exam regrades. Partly this is because I think it adds an extra layer of stress and angst if people feel that to optimize their grades they have to take extra steps after the course is over. And I know that not everybody is around or has the capacity to take those steps. Of course, it is an unfortunate reality of academic life that there are inevitably a lot of people near the cutoffs who could have gone either way, and I do appreciate how disheartening that can be. Roughly a third of the class is within four points of a grade cutoff.

The correlation coefficient between the final exam score and the combined-midterm score was .88, which is a bit higher than last year. This suggests that the midterm scores (combined) were a reasonably good predictor of the final exam score this year, though obviously there was a lot of fluctuation on the individual level.

The correlation between combined-pset score and final exam score was .66, which is also quite high but not quite as high as the midterms/final correlation (perhaps unsurprisingly, given that problem sets and exams are a bit more qualitatively different).

Of course, these are all noisy measurements, and the correlation between these measurements and the things that matter more (such as how effectively you will use your knowledge in the future) is a lot harder to quantify. So I will simply say that I have high hopes for you all!

Aside from the business of grades, let me add that I truly tremendously enjoyed getting to know so many of you this semester, and having so many interesting conversations. I hope you have both a wonderful vacation and some exciting probability-problem-filled lives. So thanks for taking the course with me! :)

All the best,

Scott

Announced on 18 December 2019  10:19  a.m. by Scott Roger Sheffield

To get a quick answer on Piazza

Hi all,

Hope you are enjoying the preparation for the final exam! I guess there are many last minute questions while you are studying, and remind that we have Piazza to ask/answer questions (https://piazza.com/class/k074p62ya25396?cid=223).

But there are some suggestions that make your questions to be answered quickly:
(1) Search with the keywords first to see if someone already asked about it.
(2) Please make the question public so that others can try (1).
(3) Please attach the screenshot or the full description of problems instead of just citing it by years. This will greatly reduce the time for pulling up problems, and also it will allow TAs or others to quickly post answers using smartphones although we are not on the desk with PC.
(4) It would be more helpful if you describe where you are stuck at or if you point out something that is not clear from the solution, because then TAs can catch your misunderstanding or what you should study more.

Good luck!
Minjae

Announced on 14 December 2019  6:41  p.m. by Minjae Park

office hours today 4:30 to 7:00 in 2-449

Just a remider that I have reserved a nice seminar room for office hours today from 4:30 to 7:00 in 2-449. I am happy to go through old exam problems or general concepts, as you wish. And maybe we take a break at 5:30 or so and eat something. (I am happy to order pizza with my arbitrage budget.)

Announced on 13 December 2019  12:09  p.m. by Scott Roger Sheffield

final week office hours

Hi all,

As I mentioned earlier, the final three lectures of the course (starting tomorrow) will be review lectures. These three lectures will be centered on a collection of problems that (together) comprise the equivalent of one final exam.

I am happy to stay after class to answer questions (tomorrow and Monday) and I will have office hours at the usual time/place (3 pm in 2-249) on Wednesday of next week.

I also reserved 2-449 (the seminar room on math department fourth floor) for a last minute office hours from 4:30 to 7:00 on Friday, December 13. The final exam is at 1:30 on Monday December 16.

Best,

Scott

Announced on 05 December 2019  11:43  p.m. by Scott Roger Sheffield