o 15210 — Syllabus

Syllabus

Please familiarize yourself with the information on this page. Not following the policies described on this page can cost you points; they are part of the "cost model."

Course Textbook

Course textbook will be made available on Diderot. Older versions are also available but beware that these are quite outdated.

Lectures

We would love to see you in class and will reward attendance. So please come, sit close to the front, and interact. Interacting with the course staff is fun and a great way to learn. Also, please note that coming to class is an excellent way to be in the know. If you don't come to class, then you will almost surely miss important things.

Regular lectures will generally occur Monday and Wednesday though we might have make-up lectures. These will be announced in class.

Grading Policy

The exams are graded on a curve, and the assignments are graded on a bucket system described below.

The grading policy is designed with the goal of reducing unnecessary stress by providing students with flexibility in managing their deadlines. Please read the policies below carefully. Following these policies closely will contribute to your grade as part of the "210 Etiquette" portion.

Our philosophy is to use grading only as a tool to encourage clarity of explanation, introspection, and self-learning. We hope that both instructors and students can think about grades in as relaxed a manner as possible. We don't want you to stress out about grades, because we don't think they matter as much as what they are made up to be. In return, we expect you to be relaxed about grading! This means that you should not sweat the few points that you might have lost in an exam and focus your energy on learning.

There will be weekly assignments (12 total), 2 exams during the semester, and a final. The due dates and exam dates will all be posted on the course schedule. The assignments will be distributed via Diderot. Each assignment will have a coding section, a written section, or both. Coding tasks will be submitted and graded on Diderot. Written tasks will be in submitted and graded on Gradescope.

Each assignment will have a total score usually between 100 and 200 points (some less). As usual, you earn points on each graded assignment. Perhaps, somewhat unusually, you don't have to earn all the points to get full credit for each assignment. Instead all you have to do is reach 80% of the total available points for full credit on that assignment.

Participation in recitation and lectures (i.e., showing up) will contribute 4 percent to your grade (equally distributed). That is to say, if you show up to 10 recitations across the semester then you get the full 2% credit. Attendance in lectures will be taken randomly.

In grading, we will reward not only correctness but also clarity and simplicity. If we don't understand your argument or solution in a reasonable amount of time, we will not give you points (because we naturally have to limit the amount of time we spend grading). We recommend that your think of your score as being inversely proportional to the amount of time it took for us to understand it. We will not argue about points taken off for hard-to-understand solutions. In order to avoid losing points for this reason, you should make sure your code is either self-explanatory or contains good comments; bad comments make your code harder to read. If you find that you score less than expected, this is probably because your solutions are not simple. In that case, take this as an opportunity to improve your skills in coming up with simple solutions and explaining them simply.

Grading your assignments is a lot of work for your TA's, especially determining the cost bounds for your code. For each coding assignment, you can help us by providing a statement of what you think your cost bound is and a short description of why you think that this bound holds. Think of this as a safety mechanism to help you avoid losing points; just as we may take off points for unclear code, we may take off points if we don't understand the costs associated with your solution. Thus you want your comments to be helpful! See the 210 style guide for an example.

As we give you some slack regarding homework, we may also choose to not grade certain questions or certain parts of each assignment (although we will grade the majority of your work). In such cases, everyone will receive a full score for the ungraded parts.

Late Assignments

Homeworks are due at 5:00 PM US Eastern Time unless otherwise indicated on the assignment or on Diderot (remember to check your email). You may submit up to two days late on Diderot and/or Gradescope, with a 10% score penalty for each day (for example, if you turn in one day late and score 85 points then you would be deducted 8.5 points).

In terms of grading, the coding and written portions of each assignment are considered separate; you could, for example, submit the coding one day late at a 10% penalty and the written two days late at a 20% penalty.

We will not grant any extensions on homeworks for any reason other than a medical condition that seriously undermines your ability to do your work, by for example hospitalizing you for more than 5 days. Common cold, flu, etc are not sufficient. In case of a serious medical condition, please ask your academic adviser to email the professors. Your advisors should include the commensurate medical justification (note that just a doctor or nurse's note saying that you went to a clinic or hospital is not sufficient). If you do not follow these guidelines closely, then you will lose points, in extreme cases, we reserve the right to assign negative Etiquette scores, possibly negating other parts of your work.

Style Grading

Handed in code will be graded for style and clarity on a pass/fail basis. You should refer to the style guide for general guidelines.

If your coding style on a particular homework assignment is sufficiently poor, then you will receive a score of 0 for the programming portion of that assignment. In order to restore your grade, you must:

  1. review the comments given on Diderot (which will detail why you failed style grading),
  2. rewrite your code for the lab (do not resubmit), making sure to address every comment, and
  3. show your new code to a TA (preferably at office hours) before the regrade deadline and explain your fixes.

If your new code is acceptable, the TA will change your style grade for the assignment to a "pass". Your original Autograded score will then be restored. It is very important that you do not attempt to resubmit any fixed code to Diderot. All submissions after the deadline are considered late, and will be graded with a penalty.

2 Week Cut-off

All issues regarding a given assignment or exam must be resolved within two weeks of the grades being released and announced (on Diderot/Gradescope). After the two week deadline, we will throw away unclaimed written feedback, and set the grades in stone. This means that if you need to contest a grade, fix a failed style grade, or have any other problems regarding an assignment, you must come to the course staff within two weeks!

To resolve any grading issues, you should talk directly to the TAs assigned to your recitation section. You may speak with them in recitation, at their office hours, or by email. Please do not send an email to the entire 15210 staff mailing list.

Exams

For extra time and other special accommodations on exams (or otherwise) students should submit an accommodation letter to one of the instructors. Please arrange your exams through the disability services office. Note that your instructors are not medically trained. If you have any kind of medical condition that require special accommodations, then please make arrangements with the relevant university services.

No make up exams are given, except possible on medical grounds and participation in university-related athletics. Interviews, going to conferences, etc are not acceptable reasons for scheduling a make-up exam. To schedule a make-up exam due to athletics related activities, please email the course staff at the staff emailing list. For medical reasons, please ask your academic advisor to contact the instructors with the relevant medical documentation that states that you are not able to take the exam due to extended hospitalization. Please do not email the course staff personally. Note that as with the assignments not following these rule could cost you Etiquette points. Because it is difficult to make sure that the difficulty of a make-up exams matches that of the given exam, instead of giving a make-up exam, we might choose to redistribute the weight of the exam towards your other exam(s) in a way. We will determine the distribution function by considering the specifics of the circumstances.

Communication: E-mail, Diderot, This Website

When you need help from the course staff, please use Diderot. Please refrain from emailing professors or individual TA's, except in cases that require privacy. Of course you are always welcome to office hours, or to ask the TAs or professor questions after class, time permitting.

Diderot Please familiarize yourself with Diderot. Its use should be intuitive but still requires some getting used to.

  1. Diderot is organized around atoms, blocks of text that are "actionable." You can ask questions or more generally make posts about atoms, bookmark them, take (private) notes on them, etc. To take or see you notes, press on the "pen and pencil" icon on the top right corner of a page.
  2. The lecture notes are divided into chapters. Each chapter is a collection of atoms organized into sections. Some atoms expand to reveal more information, such as examples, that might be particularly helpful in initial reads of the material. You can expand an atom by clicking on the triple bar on its left corner. You can also expand whole chapters by clicking on the triple bar on the right corner of the page.
  3. You can make different kinds of posts on Diderot, including feedback, question, and social. Please use the right kind of post so that important questions can be answered as promptly as possible. For example, if you have some feedback about an atom (e.g., typos), then use the "feedback" kind. If you want to share a meme that you have made, please use the "social" kind. For private and public questions, use the "Question" kind.
  4. Diderot is an educational platform. Please be kind, respectful, and civil. Any inappropriate or offensive language is not acceptable. Even if an offending post is anonymous, we reserve the right to identify the author. As a student, if you encounter such language, then please let us know.

When not to email staff. Please remember that this is a large class and refrain from unnecessarily emailing course staff. Here is an incomplete list of subjects that are included in the definition of unnecessary emails. This list is not definitive, it is your responsibility to familiarize yourself with the policies (as outlined in this document) and follow them. If you don't follow them, Etiquette points will be taken off.

  1. Waitlists. In the beginning of the semester, there will likely be a waitlist and we will make a decision about how many students to let in. We will then let the department administrators know about this decision and they will enroll waitlisted students. We cannot and do not honor individual requests. Thus, please do not email us about waitlists issues. If you did not get into the class and you were on the waitlist, the best person to talk to is probably your academic advisor and other relevant department's administrators.
  2. Deadline extensions, make-up exams, etc. See policies above.
  3. Grades, exam scores etc. Now that you are in college, we expect you to develop a value system that centers around your contribution to society and knowledge, not your grades. We value you much more than your grade or the score you get on an exam. So please do not email us matters about your scores and grades. Instead focus your energy on orienting your value system towards things that matter.
  4. Questions. Questions regarding assignments and lecture material. Please use Diderot.

We will post announcements, clarifications, corrections, hints, etc. on the course web site, and Diderot---please check them on a regular basis.

Use of Standard ML

While the lecture notes and the book use a pseudo-code language to specify the algorithms, the labs in the course nearly all involve programming in the Standard ML (SML) language. If you are a CMU undergraduate, then you should have little or no difficulty with SML. If you are not an undergraduate student or if you don't know SML or another functional language, then you might have significant difficulties in the course. Many graduate students without prior functional-programming experience have tried this course, but except for very few, have given up, primarily because the pace is too fast for learning a new language.

There are several reasons for why we use SML. The primary reason is that the course is based on the idea of designing algorithms with a clear distinction between specification and implementation, and using cost models to bridge the gap. Within the domain of functional programming, this leaves only a few languages, namely the ML family, including SML and OCAML, and a language such as Scala. We choose the ML family, because they are smaller languages and more suitable for teaching. From within the ML family, we use SML because we have developed a compiler for this language that can generate parallel executables.

The course material can in principle be taught in a non-functional lower-level language such as C/C++. But with such a language, it would be difficult (probably impossible) to cover the material covered by our labs in this course. As the students will likely experience in their last lab using C++ (PASLlab), writing correct parallel programs in imperative languages can be very tedious, e.g., even a simple bug can require many hours of low-level debugging. It can also be rewarding, however, because it is sometimes possible to write faster programs, for example, by controlling memory layout. We encourage the students to learn about these techniques in more focused courses, also taught at Carnegie Mellon.

Using a strict functional programming language such as ML can lead to some loss of performance, let say, out of generosity towards non-functional languages, 10-fold, but this usually comes with a big reduction in time needed to write correct parallel codes, let's say 5-fold. In an algorithms course, we don't worry about 10x slowdown in performance; it is absorbed by the asymptotic notation. But, a 5-fold increase in programming effort is untenable. Functional programming shields us from the complexities of concurrency and the realities of hardware, allowing us to focus our efforts on algorithmic concerns, which is the topic of this course.

Word of Caution

You will likely find this course to be difficult. There are several reasons why. First, the material covered in the course, especially parallelism part, will be new to many of you. Second, the way we design our algorithms and implement them, with emphasis on higher-order programming (where functions are first-class values), can be difficult to grasp quickly, though over time you will likely not be able to imagine thinking without them. Third, this course will require generating your own algorithms in addition to understanding existing algorithms. If you don't know Standard ML, then there will also be the additional overhead of learning a new programming language, and you should start learning it immediately. There are many online resources for doing so.

It is thus important for you to mentally prepare yourself for a difficult course. If you do your work, we are confident that you will finish this class with a satisfactory grade. As you will discover throughout the semester, we have an excellent set of teaching assistants that can help great assistance. That said, you should keep in mind that there is no substitute for doing your own work.

Academic Integrity

All students are expected to be familiar with, and to comply with, the University Policy on Cheating and Plagiarism.

Any work submitted as a homework assignment or examination must be entirely your own and may not be derived from the work of others, whether a published or unpublished source, the worldwide web, another student, other textbooks, materials from another course (including prior semesters of this course), or any other person or program. You may not copy, examine, or alter anyone else's homework assignment or computer program, or use a computer program to transcribe or otherwise modify or copy anyone else's files. It is not acceptable to look at exams from prior semesters.

To facilitate cooperative learning, it is permissible to discuss a homework assignment with other students, provided that the following whiteboard policy is respected. A discussion may take place at the whiteboard (or using scrap paper, etc.), but no one is allowed to take notes or record the discussion of what is written on the board, and you must allow two hours to lapse after any discussion before working on the assignment. The fact that you can recreate the solution from memory is taken as proof that you actually understood it.

It is not acceptable to share your solutions or give hints to your friends for a lab after you have already discovered the correct idea. You are not helping your friends by doing so. The right thing to do is to not talk about the lab after you have a solution, and anyone struggling with the homework should visit office hours to talk to an instructor or TA.

In order to deter cheating we also run automatic code comparison programs (such as MOSS). These programs are very good at detecting similarity between code, even code that has been purposefully obfuscated. Such programs can compare a submitted assignment against all other submitted assignments, against all known previous solutions of a problem, etc. The signal-to-noise ratio of such comparisons is usually very distinctive, making it very clear what code is a student's original creative work and what code is merely transcribed from some other source. Often in previous semesters, however, we have discovered cheating due to the simple fact that the TAs are familiar with many different versions of the solution. Cheating is simply not worth the risk.

One final note: receiving credit for an assignment or exam is not an indication that we did not catch you cheating. Because dealing with cheating cases is a lot of work for the TA's and the instructors, we often delay enforcement until well into the second half of the semester and take action all at once, after we identified a number of cases. This usually leads to unfavorable outcomes for the students involved. Consequences for cheating may be as severe as failing this course and being reported to the Office of the Dean of Student Affairs.