If you have any questions or concerns about these course policies, please don't hesitate to ask in lecture, during office hours, on the course newsgroup, or by email.
- How to submit homework
- Form: How to write
- Content: What to write
- Grading and regrading
- Final course grades
- Academic integrity
How to Submit Homework
Over 100 students are taking CS473 this semester. The graders will have to critically examine several thousand pages of homework submissions before the end of semester! We desperately need your help to make sure homeworks are graded and returned quickly.Logistics
- Submit your homework to Elaine Wilson in 3229 Siebel Center. There are separate folders for each problem in Elaine's office. Do not submit homeworks to the instructor, for he is fond of losing important pieces of paper.
- Turn in your homework on time. Absolutely no late homeworks will be accepted for any reason. To offset this somewhat draconian measure, we will drop the lowest grade of all the homeworks; this should take care of most unforeseen circumstances.
In cases of extreme illness or other emergencies, we may forgive homeworks or even exams. This means that your grade will be computed as if the forgiven homework or exam did not exist; your other homeworks or exams will have more weight in your final course grade. In particular, the lowest unforgiven homework grade is dropped. Please see Jeff for details.
- Each student must submit their own solutions for Homework 0. Starting with Homework 1, groups of up to three students can submit a single joint solution for each homework.
Format
Homeworks that do not follow these formatting requirements will automatically receive a grade of zero. This is not a joke.
- Use standard US Letter paper (8.5" × 11") or a close approximation. Most US notebook paper is close enough. Use both sides of the page whenever possible.
- Unless the homework specifically says otherwise, start each numbered homework problem on a new sheet of paper. In order to make the grading faster and more consistent, each homework problem is graded by a single grader and returned as soon as it is graded. If your solution for problem 3 starts at the bottom of your solution for problem 2, then the grader for problem 3 won't see all of your work.
- Clearly print your name(s), your NetID(s), the homework number, and the problem number at the top of every page. For example: "Jeff Erickson (jeffe) HW0 #5". For group homework solutions, print the name and NetID of every group member on every page. Without this information, the graders will have no idea who you are or what problem you're supposedly solving, so you'll get no credit for your work.
- If a problem requires more than one page, staple those pages together once in the upper left corner. Please do not use paper clips, tape, glue, spit, or rubber bands. Please do not try to keep pages together by folding or tearing. It is not necessary to staple single-page solutions. Please do not staple your entire homework together.
- Never write your Social Security Number on anything! Social Security Numbers are extremely valuable personal information. Anyone who knows your SSN can steal your identity with very little effort. Social Security numbers should only be used for financial transactions that are reported to the IRS.
- Nicely typeset homework will be given a modicum of extra credit. The graders get to decide what "nicely" means. I strongly recommend using LaTeX, which is far and away the best system for typesetting mathematics (and you will be typsetting mathematics). Nothing else even comes close, especially the crappy equation editor that comes with Microsoft Word. If you're a PhD student, you'll have to learn to use LaTeX eventually; might as well start now. I recommend TeXShop for Mac OS X, teTeX for UNIX/Linux (already included in many distributions), and MiKTeX for all you poor victims of the Gates Virus.
Form: How to write
Please be nice to the graders! Make it easy for them to understand what you're doing. If your answers are hard to read, the graders will be less sympathetic to your mistakes. If your answers are impossible to read, we'll just ignore them. All this goes for exam problems, too.
- Write concise, legible, and correct solutions. You will lose points for bad handwriting, spelling, grammar, arithmetic, algebra, logic, and so on. If we can't decipher what you wrote, you will get no credit. This is especially important for students whose first language is not English. If your handwriting is bad, it's time to learn LaTeX. (1337-5p33k = teh 5uxx0r!!)
- Use pseudocode or outline format to describe your algorithms. Do not turn in source code! Too much syntactic sugar distracts the reader (and the writer!) from what's the algorithm is really doing. On the other hand, raw English prose is also usually insufficient. See the textbooks and lecture notes for examples of the type of presentation we want. Ideally, your description should allow a competent programmer who has not taken this course to easily implement your algorithm in their favorite programming language.
- Make the punch line obvious. Emphasize your final answers by putting a box around them, or using a highlighter, or some similar trick.
- Omit irrelevant details. Don't turn in the piece of paper you used to figure out your answer; copy the relevant information onto a new empty page. If the same algorithm works equally fast whether the input is an array, a singly linked list, a doubly linked list, or a binary tree, try to describe it so that a competent programmer can easily use any of these abstract data types.
- Include relevant details. If a problem statement is ambiguous, explicitly state any additional assumptions that your solution requires. (Of course, you should also ask for clarification in class, in office hours, or on the course newsgroup.) For example, if the performance of your algorithm depends on how the input is represented, tell us exactly what representation you require. If your solution to a recurrence assumes a particular base case, tell us what base case you require.
- Don't regurgitate! If your answer is a simple modification of something we've seen in class, just say so and (carefully!) describe the changes. If the complete and correct answer is on page 263 of Jeff's lecture notes, the best solution you can submit is "See page 263 of Jeff's lecture notes." Period. Same with previous exams or homeworks from the current semester. You will lose points for vomiting.
However, if you find a solution from any other source, such as a web page, a journal paper, a different algorithms textbook, an official homework solution from some earlier semester, or your mom, you must rewrite the solution in your own words, and you must properly cite your sources. Assume the graders have access to all the official course material, but nothing else. While we strongly encourge you to use any outside source at your disposal, please remember that the homework is supposed to demonstrate that you understand of the material, not just how to use Google and a printer.
- Don't babble! If you don't know the answer, don't do a brain dump, hoping to get partial credit for incuding a few key words. That will never work in this class. Part of what you're supposed to learn here is how to tell when you don't know the answer. Answering "I don't know" (and nothing else) to any homework or exam question is automatically worth 25% partial credit for that question. (We will also accept "WTF?") If you try to fake it, you'll get nothing. A course average of 30% or less, or a homework average of 50% or less, is an automatic F.
Content: What to write
Convince the grader that you understand exactly what you're doing.
- Answer the right question. No matter how clear and polished your solution is, it's worth absolutely nothing if it doesn't answer the question we asked. Make sure you understand the question before you start thinking about how to answer it. If something is unclear, ask for clarification!
- Justify all your answers. Unless the problem specifically says otherwise, every homework and exam problem requires a proof. Without a proof, even a perfectly correct answer is worth nothing. In particular, the sentence "It's obvious!" is not a proof—many 'obvious' things are actually false!
- By default, if a homework or exam problem asks you to give/show/describe/develop an algorithm, you need to do several things to get full credit:
- If necessary, formally restate the problem in terms of combinatorial objects such as sets, sequences, lists, graphs, or trees. In other words, tell us what the problem is really asking for. This is often the hardest part of designing an algorithm.
- Describe the most efficient algorithm possible. The more efficient your algorithm, the more points you get. Brute force is usually not worth very much. We will not always tell you what time bound to shoot for; that's part of what you need to learn!
- Give a concise pseudocode description of your algorithm. But don't regurgitate! And don't turn in source code!
- Justify the correctness of your algorithm. You usually won't have to do this on exams.
- Analyze your algorithm's running time. This may be as simple as saying "There are two nested loops from 1 to n, so the running time is O(n2)." On the other hand, it may require setting up and solving a summation and/or a recurrence, in which case you'll also have to prove your answer is correct.
Some problems may deviate from these default requirements. For example, you may be asked for an algorithm that uses a particular approach, even though another approach may be more efficient. (See the first point in this section.) Some problems may ask you to analyze the space used by your algorithm in addition to the runing time. Exam problems will rarely ask for proofs of correctness.
- Don't make the reader extrapolate. It is never enough to explain what happens during the first one or two iterations of an algorithm, and then say "and so on". If we can't immediately tell just by looking what happens during the 17th, 42nd, or 31337th iteration, your description is incomplete. Algorithms or proofs that use phrases like "and so on", "etc.", "repeat this for all X", and "..." will get no credit. Those are perfect indications that your algorithm should have used a loop or recursion, or that your proof should have used induction, but didn't.
Grading and regrading
- Graded homework problems and midterms can be retrieved from the TA office during office hours (or whenever the TAs are around). Under normal circumstances, your graded work should be ready to pick up no more than 10 days after you submit it.
- Homework solutions will be posted a few days after the submission deadline; exam solutions willbe posted immediately after the exam ends. All posted solutions will include suggested rubrics for grading each problem; if the graders need to amend or otherwise modify these suggested rubrics, final rubrics will be posted when the grade is complete.
- Homeworks can be regraded by submitting them to any of the TAs; exams can be regraded by submitting them to the instructor. If the graders have made a simple arithmetic mistake, we will fix it immediately. Otherwise, you must also submit a brief written explanation why you think you were graded unfairly. (For example, "My answer to problem 2 is correct; see the posted solutions.") Don't revise or explain your answer; we can only grade what you submitted the first time.
If you submit a regrade request, your entire homework or exam will then be regraded from scratch. Yes, this means your grade can actually go down.
All regrade requests must be submitted at most two weeks after the homework or exam is returned. Except for arithmetic mistakes, late regrade requests will be ignored.
We will readily admit, apologize for, and correct our mistake if you have been graded unfairly. However, please remember that "unfairly" means your grade is blatantly incorrect, or that you were graded more harshly than other people in the class, not just that you think the grading standard is too harsh.
Finally, please remember that each homework point is worth less than 0.1% of your grade. Frivolous regrade requests will be met with the scorn they deserve.
Final course grades
Homework and exam grades will be reported on the course web page, using the alias you provide on Homework 0. (We may also use the campus Gradebook program.) For privacy reasons, your alias should not resemble your name or NetID. By providing an alias, you agree to let us list your grades. To comply with both fedaral law and university regulations, we cannot list your grades unless you provide us with an alias on Homework 0.Final course grades are assigned using the following algorithm. (What do you expect from an algorithms course?)
- Drop each student's lowest homework grade.
- Compute everyone's raw average, which excludes all extra credit points. Course work is weighted as follows: homework is 30%, each midterm is 20%, and the final is 30%.
- Compute everyone's adjusted average, which includes extra credit points, even from the dropped homework. (Extra credit points are not necessarily worth the same as regular points.)
- Anyone with an adjusted course average below 30% or an adjusted homework average below 50% automatically gets an F. (These are not the only ways to fail!)
- Anyone with an adjusted course average over 95% gets an A+.
- Determine letter grade cutoffs, excluding outliers from steps 4 and 5. The mean is a borderline B-/C+, and each standard deviation is worth one letter grade. (Thus, the A-/A cutoff is 4/3 standard deviations above the mean.)
- Compute final letter grades from adjusted averages, except for the outliers from steps 4 and 5.
- Adjust grades (only upwards!) at the instructor's whim.
This system ensures that extra credit can only increase your grade, that other people's extra credit does not affect your grade, and that the curve isn't skewed by the handful of geniuses and doofuses in every class. We expect roughly 25% of the students get an A- or better.
Academic integrity
This final section is unfortunately necessary, thanks to the actions of a very small minority of students.
Each student (or homework group) must write their own homework solutions, in their own words, and must properly credit all sources. We strongly encourage students to use any printed, online, or living resource at their disposal to help solve the homework problems, but you must cite your soruces. If you use something you found in a book, cite the book. If you use something you found on the web, cite the web page. If you get an idea from someone else, give them credit. This is the same standard of conduct that researchers are expected to follow for formal publications; start following it now. Citing your sources will not lower your homework grade.
Avoiding plagiarism is really very simple: Never present someone else's words or ideas as your own. Repeating ideas from other people, papers, or web pages without proper credit is plagiarism. Verbatim duplication of any source is plagiarism, including official homework solutions from previous semesters of 373/473, even if you properly cite your sources. Turning in a copy of someone else's work as your own, even with their permission, is plagiarism. Allowing other people to copy your work is also a violation of academic integrity. For more information, see the university's Policy on Academic Integrity, especially the section on plagiarism.
Violations of academic integrity will not be tolerated. The default penalty for a first offense is a grade of zero on the homework or exam, plus a 10% penalty on the final course average. The penalty for a second offense, or a particularly egregious first offense, is an F in the course. (These are the department's recomended penalties for cheating offenses.) All cheating cases are reported to the department. Multiple offenses can result in suspension or dismissal from the computer science program or from the university. More than one student has been expelled from the university (in part) because of cheating offenses in CS 473.
Regardless of whether it constitutes plagiarism, or whether you get caught, getting too much help on your homework will hurt your final grade. If you don't learn how to solve algorithmic problems on your own, you perform poorly on the (closed-book, closed-notes) exams, which make up 70% of your final course average.