What is it?
A similarity score is calculated by digitally scanning a submission against a database of journals, papers, and publications to detect plagiarism. It is important to encourage students not to focus too much on a high similarity score, but rather to focus on checking their work against what the similarity report highlights to them. The same logic should be applied when marking work.
What does it do?
Once a student has submitted an assignment using Turnitin, a similarity report is generated. This can be viewed by staff and by students (if this permission has been enabled during the assignment set up).
What Should I know?
To view the similarity report for a student, click into the assignment you wish to view, find the student, and click Similarity. This will take you to the similarity report.
The Similarity Score represents the percentage of a student’s writing that is like something found on the internet, in the Turnitin databases, or in someone else’s paper. Similarity does not mean that this work is plagiarized. Consider a student’s use of quotations, citations, and bibliographic material when reviewing this number.
You can use the filters available in the Similarity Insights Panel to strategically exclude citations, quotes, or bibliographic information from affecting a student’s score.
Similarity insights panel
The Similarity Insights Panel is the second, red panel down the right-hand side of your report.
Flags – shows evidence of hidden characters and/or text replacement within a student’s writing (see 3. Using the Flags Panel for an example).
Match Overview – shows the overall Similarity Score and the list of sources that match a student’s writing, listed from greatest to least. The colours in this list match the colours highlighted in the student’s writing.
All Sources – shows a breakdown of the sources that match the text in a student’s paper.
Filters and Settings – excludes certain information like citations, quotes, or bibliographic information from a student’s score.
Excluded Sources – shows sources that have been excluded from a student’s Similarity Report. Sources can be excluded in the All Sources tab.
Using the flags panel
There has been a new update to the Similarity Report that Turnitin generate which is only visible to staff, the Flags Panel (which is right at the top of the list, shown above). The Flags Panel can assist you in determining when a student is explicitly trying to trick the Turnitin system.
In the example given below, clicking the Flag Report gives one integrity insight to view as a priority. By clicking hidden text, you can see how many suspect characters there are (773 in the example). Consider the presence or absence of each of these elements when addressing questionable student work:
- Hidden Characters: hidden text that has been coloured white to disappear. A student may intend to inflate word count and decrease the overall Similarity Score.
- Text Replacement: characters from one alphabet being used to replace characters from another alphabet. A student may intend to circumvent similarity detection by replacing characters and making words slightly different from the original source (e.g. replacing the letter o to a small circle).
In the example given, there has been a white vertical pipe inserted into every space which Turnitin has picked up and highlighted.
This is only visible to staff, not students.