The color of the report icon indicates the similarity score of the paper, based on the amount of matching or similar text that was uncovered. The percentage range is 0% to 100% The possible similarity indices are:
Green: One word to 24% matching text
Yellow: 25-49% matching text
Orange: 50-74% matching text
Red: 75-100% matching text
If the figure is high, it does not necessarily mean that the student plagiarised as the report could be text matching against the following:
• Quotations that have been correctly referenced
• Poorly paraphrased
• Bibliography, where the citations used could be exactly the same as another student
• A common phrase or series of words used in context to the topic
There is no set number for Instructors to look for. A main reason for that is on the assignment type. For example, in a literature review, students will have to read and quote from several sources, but in a lab report, it is expected to be all the students work. You would expect to see a higher amount of similarities in the literature review than in the lab report.
Turnitin does not check to see if a piece of work is plagiarized or not. They check student’s work against their database, and if there are instances where a student’s writing is similar, or matches against one of their sources, they will flag this for your review.
If a student is using quotes or referencing correctly, there will be instances where they will find a match. The Originality Report simply allows instructors to be aware of any problem areas in a paper. Instructors will use this as a tool as part of a larger process, in order to determine if the match is or is not acceptable.
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