Myth-busting: Turnitin’s Similarity Report

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Turnitin’s Similarity Report is a useful tool for helping staff and students to identify poor academic practice and help students develop their academic writing skills. We’re conscious that there are some myths and misconceptions about the feature (and the percentage scores it produces) – what it’s for, how to interpret it, and what it means. In this blog post, we’ll be busting the most common myths and suggesting ways to optimise your use of this tool to help your students develop their academic practice.

Myth: Turnitin is a plagiarism checker.

Buster: No, it’s not. Turnitin only indicates matches to text in its database and on the internet. Your academic judgement is still needed to review the matches and determine whether anything has been copied or plagiarised.

Myth: A higher percentage of matched text (a high percentage score) means a student has plagiarised or colluded.

Buster: Not true. Turnitin’s Similarity Report compares the student’s submission to millions of online sources held its repository and searches for matches. A high score does not automatically mean the work has been plagiarised; the student may have included lots of references and cited them, for example. You can also use the in-built filters to refine the matches shown and exclude referenced work and short phrases.

Myth: There is a certain percentage score above which the student’s work should be investigated for plagiarism or collusion.

Buster: There isn’t an ideal percentage score you should ask your students to meet, nor a score above which plagiarism should be investigated.  Indicating a percentage to students can give a false sense of security and not necessarily help them to correctly cite their sources or appreciate how to balance quoting and paraphrasing others with their own thinking. It can also give students an inconsistent experience and lead to unnecessary anxiety when working on assignments with different requirements for referencing sources. A student with a low similarity score may have plagiarised, another student may have a included a lot of directly quoted material leading to a high score. Don’t rely on the overall percentage score. You’ll still need to use your academic judgment by checking the highlighted matches as you mark.

Myth: The colours used in the Similarity Report Index indicate where plagiarism has been committed – green is fine, red is bad.

Image of Similarity Report score ranges

Buster:  Again, not true. Blue, green, yellow, orange, and red are simply used to indicate the amount of text matched to online sources. Green (one word to 24% matching text) could still mean a student has directly copied and pasted content. Orange (50%-74% matched text) could mean a student has copied and pasted, but it could also indicate an over-reliance on direct quotation because of poor academic writing. Your judgement is needed here.

 

 

Myth: I can solely rely on the Similarity Report to determine an instance of plagiarism or collusion.  

Buster: No, you should not just rely on this tool but use your academic judgement as well. Based on your knowledge of the subject and literature and of your students, you can sense from prior work, the style and tone of the assignment, whether it’s authentic.

Myth: Turnitin is just a tool to catch students who plagiarise. It should only be available to students after they’ve submitted their work and after the deadline.

Buster: Whilst the Similarity Report can help you identify plagiarism, it can also help you identify poor academic practice. It can be used developmentally with students to help them improve their understanding and writing skills. The Similarity Report can be used formatively as students are completing their work (by allowing them to submit drafts). Building in the use of the report as a formative assessment activity can help them improve their academic writing and understanding of academic integrity.

Want to improve your use and understanding of the Similarity Reporting feature?

Read the support guides:

Book onto one of the forthcoming 1-hour staff development workshops:

TEL: Interpreting the Turnitin Similarity Report (Webinar)

  • Wednesday 25 October 2023, 09:30-10:30
  • Thursday 16 November 2023, 14:00-15:00

Book your place here

 

Lauren McCann & Chris Johnson (CQSD TEL)