18.440  Probability & Random Variables

final

Dear class,

In response to questions, I wanted to reiterate that the exam is cumulative. The set of problems covered during the last three lectures (about ten total, if I recall) are an excellent representation of what the actual final exam will be like. The "practice final" on the website is only meant to give you extra problems on the latter part of the course.

If you want to make a more representative "practice final" for yourself, try taking

1. A few problems from one of the Midterm 1 exams (from some year) or the practice midterm 1.

2. A few problems from one of the Midterm 2 exams (from some year) or the practice midterm 2.

3. A few problems from the practice final.

Cheers,

Scott

P.S. I'm still in the hospital (this is a rather persistent bug...) but feeling much better than before. I appreciate your patience and apologize for not having been more responsive this week.

Announced on 17 December 2011  10:18  p.m. by Scott Roger Sheffield

Psets

Dear all,

the end of the semester is now coming. We have had some issues with problem sets that didn't have names on them. If you found yourself in the situation where you know you solved Pset n, you know that you turned it in on time, but never received a grade for it, then very very likely you didn't put your name in the Pset. So your Pset is indeed graded but we didn't know who you were. What you should do is go to 2-108 and seriously look carefully over the pile of Psets that you can find there. Pick up yours and then communicate with me.

Best
Benjamin

Announced on 15 December 2011  3:49  p.m. by Benjamin Iriarte Giraldo

end of class issues

Dear class,

I've been in the hospital with bacterial pneumonia since Monday evening. Overall prospects are good, but it's a tough little bug. (I had originally hoped to be better in time for the final lecture this morning, but that was obviously too ambitious.) Sorry to abandon you in your time of need, but I hope you at least enjoyed Ivan Corwin's substitute lecture.

Ben has graciously agreed to handle your last minute logistical questions, math questions, grading questions, meeting requests, etc. You are welcome to write to me, but my ability to respond is somewhat unpredictable. (I feel pretty good at the moment, but I sometimes go for eight hour stretches during which I can't do anything but breathe, and even that is tough... lots of ups and downs so far...) So it's probably best to only write to me if you have a question that only I can answer.

1. Please fill out the online course evaluations right now before you forget. (The first time I taught this course, I didn't nag at all, and almost nobody filled out an evaluation, which I felt bad about.)

2. Solutions sets for all homeworks are available at the Stellar site, under the materials tab.

3. Graded homeworks and midterms can be picked up in 2-108.

4. The most important thing to do when studying for this exam is to make sure you thoroughly understand all of the homework problems, as well as all of the concepts, derivations, and problems presented in the lecture slides. The textbook covers essentially the same material and is good to read if you want more explanation than is contained in the slides. (Black-Scholes and martingales can also be reviewed in the assigned Wikipedia articles.)

5. All lecture slides for the course are available at the course web page:

http://math.mit.edu/~sheffield/fall2011math440.html

Announced on 14 December 2011  6:41  p.m. by Scott Roger Sheffield

dropbox issues

Dear class,

Our beloved dropbox (which I find to be a rather convenient way to post lecture slides) has been having some glitches lately, meaning that some people have not been able to access the lecture slides from the course web page.

I hope that these glitches will be fixed soon, but in the meantime the slides are also available at the following URL:

http://ocw.mit.edu/courses/mathematics/18-440-probability-and-random-variables-spring-2011/lecture-notes/

Best,

Scott

Announced on 13 December 2011  11:59  a.m. by Scott Roger Sheffield

Exam thoughts

Dear class,

The second midterm exam solutions are up and the grades are available at stellar.

The class average was 70.

About 60 percent of the class scored above 65.

About 10 percent of the class scored below 40.

The class high was 98.

The exam average was a little lower than last time, I think mainly because of a couple of wording issues that threw people off. If 1 b had been worded "Let N be the number of times that the die comes up either 1 or 2. Compute the variance of N." then I think most people would have gotten it right. (As it is very few people got it right.)

I also suspect that a few more people would have gotten the javelin problem right if it had been phrased in terms of decay times of radioactive particles instead of javelin throw distances. Sometimes these little leaps are hard to make under time pressure.

Please come and talk to me in person at office hours on Wednesday if you would like to discuss any issues related to your performance, your grade, or the course material. I will leave the exams for pickup in 2-108 on Monday.

All the best,

Scott

Announced on 18 November 2011  6:06  p.m. by Scott Roger Sheffield