Syllabus

If you have any questions or concerns, please don't hesitate to ask in lecture, during office hours, or by email.

TL;DR: Be honest, cite your sources, and if you need help, please ask me for that help. I am here to help, but I can't help if you don't ask.

If you have any doubts about whether something constitutes plagiarism, talk to Jonathan, and err on the side of caution. I will not penalize you if you tell me what happened before turning in the assignment. I will not consider it an academic integrity violation if you inform me what happened before you submit.

I strongly encourage you to use any printed, online, or living resource at your disposal to help you solve homework problems, but you must cite your sources.

• If you use an idea from a book, cite the book.
• If you use an idea from a paper, cite the paper.
• If you use an idea from Wikipedia, cite Wikipedia.
• If you use an idea from CS StackExchange, cite CS StackExchange.
• If you use an idea from another student, cite that student.

This is not an exhaustive list!

There are only two exceptions to this rule. You are not required to cite the following:

• Official course materials (lectures, lecture notes, readings, and exam solutions) from this semester
• Sources for prerequisite material (which I assume you already know)

Verbatim duplication of any source, even with proper citation, is plagiarism. In particular:

• Copying verbatim from textbook solutions, old CS 401 solutions, or a generative AI model is plagiarism.
  • Using a generative AI model to help polish your own writing is not plagiarism, as long as you explicitly declare your use of that AI in your submission.
  • Using a generative AI model to polish or rewrite someone else's writing and submitting the result as your own work is plagiarism.
• Submitting work done entirely by another student is plagiarism, even if you have their permission.
• Allowing another student to copy your work verbatim is also an academic integrity violation.
• Making simple lexical changes, such as changing word order or changing variable names, still counts as "copying verbatim" for purposes of this policy. It's still plagiarism.

Classes in some other departments allow and even encourage verbatim copying in small doses. For example, if you want to claim that an expert holds an important or controversial opinion, it is usually better (more honest, more accurate) to quote them verbatim, instead of rewriting their opinion in your words. But computer science classes are different. I won't ask you to defend a hypothesis or opinion using evidence or rhetoric. What I will ask for are formal, logical, mathematical arguments. Expert opinion is irrelevant here; the math must speak for itself. In particular, I am asking you to demonstrate your expertise in formal, logical, mathematical reasoning and communication. You can only demonstrate expertise in something by actually doing it.

That said, if you want to use an algorithm from the textbook, lectures, or previous homeworks in your solution, just use it (and cite it) and carefully describe any necessary changes.

I have listed a (relatively) short list of “common” smaller ways that people plagiarise – there are a number of more egregious ways to violate the university's academic integrity policies, such as collaborating with or copying from another student during an exam, hiring an impostor to submit homework or take exams for you, falsely claiming to have submitted a homework or taken an exam, and modifying or destroying other students' graded work. Just because something is not explicitly listed in this document does not automatically make it okay; please use common sense.

Given all the hype around ChatGPT and similar AI language models, many students are tempted to use them to “help” with homework. As policy, I am treating language models just like every other source—you are welcome to use it, provided you cite it and write your answers yourself in your own words—but I also want to caution you about relying on them too much.

ChatGPT and similar models are designed to produce plausible-looking text. Despite breathless language to the contrary in innumerable press releases, ChatGPT does not “know” or “understand” anything; anyone who says differently is selling something. A good high-level summary of the problem that ChatGPT solves, over and over again, is “Here are seven consecutive words from a sentence; what's the most likely eighth word?” Basically, it's a grownup version of Dissociated Press.

You should think of ChatGPT as an incredibly imaginative toddler. They're very good at telling stories, and can expound—fluently and authoritatively—about any topic you give them but in fact, everything they “know” about the topic comes from some vague snatches of words they heard adults around them say. Sometimes our toddler gets lucky and says the right thing by accident – a broken clock is right twice a day – but as a rule, they're just saying words that sound like they could plausibly go together. In particular, even for topics where they're likely to mirror the right high-level intuition, unless they are directly quoting something that it's heard before (and therefore, by my definition, plagiarising, since ChatGPT isn't so great about the whole cite your sources thing), the fine details are likely to be fictional or incoherent.

You should also remember that ChatGPT was trained on text from the internet; the influence of large crowd-sourced sites like Geeks4Geeks and StackExchange—whose content quality can be charitably described as high-variance—is quite clear. Relying on ChatGPT is roughly equivalent to relying on the average self-proclaimed internet expert, or perhaps more accurately, on the average self-proclaimed internet expert's parrot. (More specialized models, trained on more carefully curated data and able to check their own work, yield better solutions for simple math and programming problems, but even for those simple problems, “better” is still not good or correct.)

That doesn't mean you can't use ChatGPT (or Geeks4Geeks, or any other questionable source) to help you solve homework problems. After you make a good-faith effort—at least a couple of hours—to make progress on your own, then it can be useful to ask ChatGPT, and then try to figure out what's wrong with ChatGPT's answer. Once you understand what ChatGPT did right and wrong, you're in a better position to write your own answer, in your own words.

In fact, this is the approach I would suggest for any source, including the official course materials. Work on your own first, assume that your source has errors, find those errors (or prove to yourself that there are no errors), then go back to working on your own. (Hopefully the official course materials have fewer bugs than ChatGPT's output, but yes, they have bugs.)

You are strongly encouraged to seek out general resources beyond official course resources (other textbooks, lecture notes, etc.) — very often it takes two or three different explanations for a concept to click, so finding different explanations is a good thing — with the following caveats:

• Definitions and terminology can differ significantly (and subtly!) depending on the author. Be careful that other resources are saying what you think they are saying, and if something conflicts with what I teach in class, I will consider what I teach in class to be correct and anything else incorrect.
• You may not search with the intent of finding a solution to a specific homework problem (see below).
• You may not use commercial tutoring resources like Chegg for the problems I ask, nor post course materials or your answers to those websites.

While you are permitted to seek out general resources, you may not search intending to find answers to the problems I ask you on homeworks. I choose and design problems for their pedagogical value; the number of pedagogically-valuable problems is limited for some of these topics, so similar problems are likely to appear elsewhere.

• You may not use a written solution for an equivalent problem as a resource, but you may use a written solution for different problems on the same topic (i.e., other divide and conquer proofs are a fine resource).
• You may not post these problems on the internet (e.g. on Chegg, Reddit, or other sites).

Almost every instance of plagiarism I have seen was motivated by a combination of two factors.

The student feels overwhelming pressure to improve their performance, despite gaps in their understanding. The student might be overwhelmed by work in other classes, or financial pressure to graduate, or parental/cultural expectations. This might be the hardest course the student has ever taken, and their merely good performance is a blow to their aspirations or self-image. The student may be suffering from Impostor Syndrome, the feeling that they really aren't good enough to be here (despite evidence to the contrary), and that their fraud will be uncovered if they admit that they can't do something. The student might have trouble with English, and therefore worries that rewriting someone else's text would distort the meaning. Perhaps the student is dealing with depression, serious illness, divorce, or a death in the family. Or maybe the student simply sees no way to satisfy the instructor's unreasonable or unclear expectations without cheating.

• If you find yourself in this situation, ask for help! If you need help understanding the material, come to office hours, ask questions in class, talk to your fellow students. I will even make extra appointments to help guide you through the material or give you feedback on tentative solutions, but only if you ask. (But please remember that my goal is to help you master the material, not just to help you get a better grade.)
• If you think a homework problem is unclear, please ask for clarification. Your confusion might indicate a gap in your understanding of the course material, but it might also indicate that the question is poorly stated, unfairly hard, or even impossible. My job is to help you learn the material; please let me know if I'm not doing my job.
• I do expect solutions to be written in clear, coherent English. If you are thinking of copying someone else's words because you are uncomfortable with English, you are probably better off stepping back to improve your English skills might be more important than getting a good grade in this course.
• Asking for help does not make you “look stupid”. Quite the opposite — it means you are smart enough to recognize your own limitations and work to overcome them. Asking for clarification is not an insult to the instructor. Again, it's the opposite — questions are valuable feedback that I can use to teach more effectively. Everyone suffers from Impostor Syndrome occasionally, including your professors. Most importantly, please remember that your grade is not a statement about your intelligence, your potential for success, or your worth as a human being; it's only feedback about your mastery of the course material.
• If your situation is very serious, or not directly related to this class, you may prefer to discuss your situation with your department or college advisor, a family member, a trusted friend, or the counseling center, but please talk to someone.

The student is used to an academic culture where plagiarism is tolerated or even encouraged. Maybe they come from a high school with litigious parents who discourage teachers from punishing cheaters. Maybe they come from a country where students are expected to parrot back their instructors' exact words to demonstrate understanding. Maybe they've been trained by their previous classes to optimize points, even at the expense of honesty, instead of learning. Maybe cheating was inconsistently or ineffectively enforced in their past classes; they've seen cheating students succeed (getting higher grades, or even better jobs) where honest students have suffered.

• Please be aware that my standards for academic integrity may be different than what you're used to. This point is especially important for international students. The standards I apply in this class are a proper subset of the standards applied to Illinois faculty and most other professional scientific researchers. (Fortunately, we don't have to worry about authorship and author ordering policies, accurate recording and reporting of experimental results, or ethical issues with animal test subjects.)
• My job as an instructor is to help you master the course material. I ask that you write everything yourself so that I can make an honest assessment of your mastery of the course material, and therefore give you useful feedback. I allow wide latitude in choosing the resources you need to learn, because I believe that freedom will help you learn more effectively. I trust that you will use those resources responsibly and ethically. Plagiarizing other people's work to improve your grade is an abuse of that trust. It is unfair to yourself, to me, and to your fellow students.
• I am painfully aware of differences in cheating policies and their enforcement in different classes, both within and outside the computer science department. Within the guidelines of the Student Code, the university gives faculty broad discretion (under the rubric of academic freedom) in defining what constitutes “cheating” and how strictly cheating policies are enforced. Sometimes these differences lead students to believe that cheating policies are overly restrictive or inconsistent, and so can be justifiably ignored.
• I believe that my policies are fair, but even with the best of intentions, people make mistakes. If you believe that any policies in this course are unclear, unreasonable, or inconsistently applied, I strongly encourage you to voice your concerns to me and/or the department administration. If you wish to complain anonymously, feel free to contact the department administration directly.

Very rarely, students cheat simply because they want a good grade (or a degree) at all costs, with no thought whatsoever for learning or fairness. I have absolutely no sympathy for these students. You have every right to rob yourself of the educational opportunity you (or your parents) have paid for, but don't expect me to help you.