To refine your students' similarity scores, consider the following Similarity Report filters:
You can exclude sources in the source list that are below the threshold set by you. For example, if the threshold is set at 3%, any 1% or 2% match would be removed from the current report mode's source list (Match Overview or All Sources).
Quotes and bibliography items are widely reused and generally fail to demonstrate original writing. You may wish to exclude quotes, bibliographies, and items of a similar nature from influencing your students' similarity scores.
The source exclusion feature is generally used when a paper has been submitted more than once to Turnitin (possibly as draft submissions). Sources may also be excluded when an instructor agrees that students use a certain source for their writing.
If you believe an item may have been added to the Turnitin database since a Similarity Report was last generated (this could be a website, journal article, or even another student’s paper), you can generate a new report to receive an up-to-date score.