Plagiarism, Authorship & Citation
Research depends on accurate credit: who did the work, whose ideas these are, and where the evidence came from. Most failures of credit look minor: a paragraph reused without acknowledgement, a name added as a favor, a statistic cited from a paper you never read. Each one still misrepresents the record. This lesson covers the three places credit goes wrong: the words (plagiarism), the byline (authorship), and the sources (citation). Then it gives you six realistic dilemmas to work through.
Plagiarism is more than copy-paste
Plagiarism is presenting someone's words, ideas, or work as your own. It comes in more forms than students expect:
- Verbatim. Copying text word-for-word without quotation marks and a citation. The obvious case.
- Mosaic / patchwriting. Swapping in synonyms and shuffling a source's sentence while keeping its structure. Adding a citation doesn't fix it. If the wording is still theirs, quote it. If you're paraphrasing, restate the idea in your own sentence structure.
- Self-plagiarism. Reusing your own previously submitted or published work as if it were new: recycling last year's essay into your thesis, or republishing the same results. Your own words still need disclosure and, where the earlier work was assessed or published, a citation.
- Idea theft. Taking someone's argument, design, or unpublished finding and presenting it as your own, even if not a single sentence is copied.
Paraphrase, done right: read the source, look away, restate the point in your own words and sentence shape, and cite it. Cite for the idea, quote for the wording. Both need attribution: a citation covers the idea, quotation marks cover the exact words.
Who counts as an author
Authorship means credit and accountability, so it can't be handed out as a gift or a thank-you. The widely used ICMJE standard asks for all four of these, not just one:
- Substantial contribution to the conception, design, data, or analysis;
- Drafting the work or revising it critically for important content;
- Final approval of the version to be published;
- Accountability for the work, agreeing to be answerable for its integrity. This last one is why an AI tool cannot be an author however much of the drafting it did: software cannot answer for anything.
Two failures follow directly. Gift (or honorary) authorship lists someone who didn't meet the criteria: a lab head, a friend, a favor for a CV. Ghost authorship omits someone who did: the student who ran the study, or an industry writer kept off the byline. Both distort who is responsible. People who helped but don't meet all four criteria belong in the acknowledgements, not the author list. Author order should reflect contribution and be agreed openly and early, with a contributions statement, or with co-first authorship when the work was equal.
Citation ethics
A citation tells the reader where a piece of knowledge came from, so two rules matter. Cite what you actually read. If you found a 1998 statistic quoted in a 2020 review but never read the 1998 paper, don't cite the original as though you did. Read it, or write "(1998, as cited in 2020 review)". Citing sources you've only seen second-hand brings unverified claims into your work and passes on any errors. And cite generously and accurately: attribute ideas to whoever had them, don't inflate your reference list with papers you didn't use, and don't strip a citation to make an idea look original. The mechanical part is a check, not a judgment call, and it belongs in the final pass. Every citation in the text must appear in the reference list, and every entry in the list must be cited.
Work the dilemmas
Here are six situations you could plausibly face. For each, pick the response you think fits the guidelines, then compare it with the guideline-based answer and its reasoning. These are judgment calls, so the reasoning matters more than your score.
⚖️ Authorship & citation dilemmas
Pick a response, then reveal the guideline-based answer.
Credit follows contribution. Whether someone belongs on the byline depends on the work they did, not on their seniority, their feelings, or a favor owed. Whether a source belongs in your references depends on whether you read and used it.
Why it matters: plagiarism and authorship disputes are among the most common and most career-damaging integrity cases students face. Almost all of them can be avoided with habits set early: paraphrase properly and quote when in doubt, agree authorship and order in writing at the start of a project, and cite only what you've read. When a case is unclear, ask your supervisor or your institution's research-integrity office before you act, not after.
Common questions
Can I reuse text from my own earlier assignment?
Not by silently pasting it in; that is self-plagiarism. Reusing your own previously submitted or published work as though it were new misrepresents it, and most institutions treat re-submitting an assessed essay as an academic-integrity issue. If the earlier work was graded or published, cite it. Rework the material for its new context, and do not drop identical paragraphs into a thesis. Swapping a few words to disguise the reuse (patchwriting) does not help. Building on your own earlier writing is normal and fine, as long as you disclose it, cite it, and rewrite it. If you are unsure of your program's specific rules, ask your supervisor before you reuse anything.
Does my supervisor automatically get authorship?
No. Authorship depends on contribution, not on job title. Under the widely used ICMJE criteria an author must make a substantial contribution to the work, help draft or critically revise it, approve the final version, and agree to be accountable for it. A supervisor who shaped the design, guided the analysis, and revised the manuscript clearly qualifies, and in practice many do. But merely heading the lab, providing funding, or giving occasional feedback is not enough on its own; listing someone on that basis is gift (honorary) authorship. The opposite error (dropping a student who did qualifying work) is ghost authorship. The fix for both is to agree authorship and order openly and early, based on who actually does what.
How much do I have to change a sentence for it to count as a paraphrase?
No number of changed words makes it safe. Swapping in synonyms while keeping the source's sentence structure is patchwriting whether you changed three words or thirty, because the structure is still the author's. A better test is a procedure: read the passage, put it out of sight, and write the point from memory in the form your own paragraph needs. If you cannot do that, you do not yet understand the passage well enough. Then cite the source anyway. Paraphrasing removes the need for quotation marks, but never the need for attribution. If you want to keep the original wording, quote it.