Limitations of Turnitin
What Turnitin cannot match
Turnitin can only match text in students’ work, not images. Turnitin cannot match students’ work to web sites which require a login or those which do not allow search engines to add them. Although Turnitin regularly checks web sites for updates, very recent updates may not be matched. Turnitin cannot match to text books, unless they are publicly available in digital format on the internet. Finally, the way Turnitin works means that it will tend to show matches at the level of sentences or more which are similar (they don’t have to be exactly the same). Where you may see smaller –or ‘fragmented’ –matches, it is because there are several parts of the student’s work which matches the same source. You will not see a single fragmented match to a single source.
As assessment types are becoming more varied for students, there has been a noticeable increase in the number of PowerPoint or ‘poster’ submissions. Although the file formats are accepted by Turnitin as part of their usual File Requirements, it is key to note that as Turnitin is predominantly a text-matching service it cannot capture for onscreen feedback all of the visual elements that are offered by PowerPoint which students may wish to use. Please read PowerPoint and Poster Submissions Limitations for guidance and tips.
Text matches DO NOT mean Plagiarism – it is Academic judgement
The Similarity Report does not indicate that an assignment has or has not been plagiarised. It simply shows where some of the student’s text is unoriginal. Some unoriginal text might be as quotes and some might just be ‘common language’. Turnitin is a tool to help you identify sources of matching text. The decision as to whether work has been plagiarised or not, lies with you and your School and should be made only after careful examination of the submitted work.
Matching sources are not definitive
Where Turnitin indicates a possible source for matching text, it is not necessarily the source. For example, many websites may have the same text. Turnitin indicates what it considers the ‘best match’ first.
For further help and guidance please see Turnitin’s own help resources