Similarity Reports provide a summary of matching or highly similar text found in a submitted paper. When a Similarity Report is available for viewing, an icon will appear in the Similarity column of the Assignment Inbox. Similarity Reports that have not yet finished generating are represented by a grayed out icon in the Similarity column. Reports that are not available may not have generated yet, or assignment settings may be delaying the generation of the report.
Note: Overwritten or resubmitted papers may not generate a new Similarity Report for a full 24 hours. This delay is automatic and allows resubmissions to correctly generate without matching to the previous draft.
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:
Turnitin does not check for plagiarism in a piece of work. Instead, we will check a student's work against our database, and if there are instances where a student's writing is similar to, or matches against, one of our sources, we will flag this for you to review. Our database includes billions of web pages: both current and archived content from the internet, a repository of works students have submitted to Turnitin in the past, and a collection of documents, which comprises thousands of periodicals, journals, and publications.
It is perfectly natural for an assignment to match against some of our database. If your student has used quotes and has referenced correctly, there will be instances where we will find a match. The similarity score simply makes you aware of any problem areas in a student's paper; you can then use this as a tool as part of a larger process, in order to determine if the match is or is not acceptable.
As an example, your student may have submitted a paper to Turnitin in the past. If they had their name on that submission, it is entirely possible that, if you have opted not to exclude small matches, you may see this highlighted in their similarity report.
Another example may concern a student copying and pasting a chunk of text into their paper, due to a lack of knowledge on the topic they are covering. Their similarity score might be 10%.
However, this might be compared to another student who has a firm basis of knowledge for the paper and knows enough to gather information from several sources to quote and reference correctly. Their similarity score might be 12%.
Both students will be shown to have matches against our database. However, one of these students copied directly from a website, whereas the other provided properly sourced quotes.