CMPSCI 601: Theory of Computation

Offered through the PEEAS distance learning program

David Mix Barrington

Summer, 2003

This is the home page for the summer 2003 offering of CMPSCI 601. CMPSCI 601 is the graduate core course in the theory of computation and will deal with formal languages, computability, logic, and complexity theory.

This course is being offered only through distance learning by the UMass PEEAS program. Please contact them for any information concerning registration.

Students in the course have been mailed videotapes of the lectures I gave in the Spring 2003 offering of this course. Extensive notes for these lectures are available on the Spring 2003 website.

There were six homework assignments, a midterm exam, and a final exam which determined the grade. See the directory pages linked above for scheduling. I hope the Spring 2003 questions and solutions were useful as a study guide.

Announcements (25 August 2003):

I have now graded the finals and assigned final grades. The exam and solution are now posted. The five exam scores, in descending order, were 61, 46, 45, 39, and 26. The final grades were four BC's and a C for the five students who took the exam. I will email detailed grade summaries for the final, probably tomorrow.
I have given the final exam to the PEEAS office Tuesday afternoon. The preferred time to take the exam is Friday 22 August -- please email me with any questions.
The HW#6 solution has been posted. I have also emailed out individual grade reports -- the five scores (in descending order) were 75, 58, 46, 36, and 33.
I fixed a typo on Question 2b on HW#6 -- the variables called "t" and "m" in the old version should be the same.
You can find the practice and real final exams from the Spring course here. The final for this course will be similar, covering the whole course but emphasizing the material after the midterm.
I have added an extra credit question to HW#6.
I've just posted the questions for HW#6, though I've not debugged them carefully. Email me with any questions! HW#5 grades have now been emailed to each of you. The HW#5 scores were (in descending order) 41, 38, 31, 24, and 16, out of 85 points rather than 100 because I messed up Question 4.
I've just posted solutions to HW#5.
I've posted solutions to HW#4.
I have graded the HW#4's and sent email grades and comments. The five grades were (in descending order) 64, 59, 53, 47, and 34. I've also posted the questions for HW#5, due next Monday. I checked these over and added the words "poly-time" in one place today.
I have posted the midterm exam and solutions for it linked from the new exam directory page. I have emailed each of the remaining students with the results of the midterm. The grades were (in descending order) 50, 49, 48, 43, and 38, all in the BC range.
I have posted the HW#4 assignment, due a week from Monday. I have adjusted the due dates of HW#5 and HW#6 as well. Please plan to take the final exam by Friday 22 August, because grades are due at noon EDT on Monday 25 August.
The final version of my notes with comments on HW#2 and advice for the midterm is now posted. A quick summary is:
- Know what you are talking about! You need to know the type of every variable you use, and whether the way you are using it makes sense.
- Keep coming back to the definitions, which will tell you what to do to prove what you want to prove.
I have given the midterm to the PEEAS office, so your proctors should receive it on Monday 21 July. As it turns out one student can't schedule it until at least Thursday 24 July, so I'll give you until then to take it. (Of course whenever you actually do take it, you get one period of 90 minutes with no books or notes.)
I've graded the HW#2 and HW#3 responses from the five of you who are still taking the course. (If you didn't do HW#3 and intend to continue, please let me know by email.) The HW#2's were not very good -- the five scores were 18, 30, 35, 37, and 49. I will drop the lowest of the six HW grades, so the rest will count 7% each, but clearly you have to figure out what went wrong on these (by studying my solutions) to do well on the test. The HW#3 results were better: 60, 78, 80, 95, and 100.
The midterm covers lectures 1-15, not 11-15, sorry! The format and content will be similar to the two Spring 2003 tests, the practice and real midterm exams. Solutions for both these exams are available linked from here.
Sorry I have not updated this in a while! I've received HW3 responses from five of you, and will send you summaries of your scores by email. I've also mostly graded HW2 and will send email reports on that, probably tomorrow.
I will be traveling from Thu 3 July through Sat 12 July, and will be away from email for some of that time. I will be able to respond to email questions, but it may be more complicated for me to update the Q&A file remotely. During this time you should be largely engaged in reading the LPL book and doing HW#3, for which the Grade Grinder will itself give you useful feedback.
I was asked about a practice midterm -- you have the practice and real tests from the Spring 2003 course, which should be enough practice. I'll be making the real midterm with the same format and difficulty as those two exams.
I've posted homework assignment #3, due on Tuesday 15 July, and solutions to HW#2.
I've corrected some typos in HW#2 (note that corrected text there is in green) and added the clarification that Question 3 there deals with one-tape Turing machines only).
Note that HW#3 will involve questions from the LPL book that will be mechanically graded by a server connected to the LPL people. This means that you must buy the LPL book and register as a user following the instructions there. (If you've already bought LPL for a previous course, you may reregister for no additional charge.) Note that used copies of LPL are in general not usable if the prior owner has registered themselves. I'm sorry about this, but it's the procedure that this textbook publisher has insisted on and I need to follow it in order to use the textbook.
I've made a correction in the statement of Problem 4 on HW#2. The first hypothesis on A is meant to be exactly one of the hypotheses of the Rice-Myhill-Shapiro theorem from lecture.
I've graded HW#1 and posted solutions. These were generally disappointing, with only about three of them showing good understanding of the material. I'll email out individual grades.
It is a very difficult undertaking to learn the material of a graduate course at a top-rank research program at an accelerated pace while carrying out a full-time job. Some of you may not be up to it this summer, and those of you who succeed will need to work very hard.
I've just posted the assignment for homework #2, due a week from Tuesday. I will be away from email until Sunday morning. I will post some general comments on HW#1 when I get back.
I've put the tentative due dates for all six HW assignments on the homework assignment page. I'll post the questions for HW#2 by Friday, it is due on Tuesday morning 1 July. The midterm may be taken during the week of 14-18 July and the final during the week of 18-22 August -- grades are due on Monday 25 August.
I've discovered I won't get a chance to grade any HW#1's until 2:00 pm (EDT) on Friday 20 June 2003, so I will accept faxed submissions until then for full credit. Express-mailed submissions may arrive on that day, Friday.
The Q&A page now contains several more answered questions about HW#1.
The first homework assignment is now posted. It covers lectures 1-5, and is due Fri 20 June. Be sure to read the policy on academic honesty on the homework assignment page.
I have now received the shipping schedule from PEEAS for the videotapes of the lectures.

Textbooks: First see the textbook notes on the spring 2003 page. It turned out that while the notation of the lecture notes is that of [P], we didn't use [P] all that much and you may or may not want it as a required text. If I assign any homework problems out of [P] I will give their text in full on the web site.

The Sipser book may or may not be useful to you -- it is a very readable treatment of some of the course material.

We will use the LPL book as we did in Spring 2003.

I am told that the Jeffrey Amherst Bookstore no longer stocks [P], but one student reports that he was just able to buy both [P] and Sipser for $65 on-line.

I welcome email questions on the lectures, the homeworks, or any other topics. I will post interesting questions and their answers on this page, without identifying the questioner. You may be interested as well in the questions and answers from Spring 2003.

Last modified 25 August 2003