What do those SafeAssign scores mean?

As a paper grader I use a tool called SafeAssign.  From Blackboard:

  • Scores below 15 percent: These papers typical include some quotes and few common phrases or blocks of text that match other documents. These papers typically do not require further analysis, as there is no evidence of the possibility of plagiarism in these papers.
  • Scores between 15 percent and 40 percent: These papers include extensive quoted or paraphrased material or they may include plagiarism. These papers should be reviewed to determine if the matching content is properly attributed.
  • Scores over 40 percent: There is a very high probability that text in this paper was copied from other sources. These papers include quoted or paraphrased text in excess and should be reviewed for plagiarism