Symptom

Student submits paper once, revises, then submits again. Originality Index of the revised paper is higher than the original paper.

Cause

Most likely, Turnitin is comparing the revised paper to the initial submission.

This happens because:

(in Turnitin) the default is to finalise on first submission.
- Instructors may miss the option for not finalising Originality Report on submission as the option is located in Optional Settings.
(in IVLE) the student submits different versions of one paper to the submission folder using different file names.
- Student ignores warning in IVLE that resubmissions should use the same file name.
- Turnitin then treats the two versions as separate, comparing the recent one to the one previously submitted.
(in Quick Submit) the staff checked the Add file to Turnitin's repository option.
- Once a file is added to Turnitin's repository, the submission of a revised paper is checked against the earlier submission.

You can exclude the source leading to the skewed Originality Index, OR
Contact the NUS Turnitin Administrator to request for paper deletion from database. The admin will send a deletion request to Turnitin. Please provide the following information:
1. If you used Turnitin directly: The Class ID and Paper ID.
2. If you used Turnitin IVLE Workbin integration: Your NUSNET ID, the module code, Workbin name, document title and name of person who uploaded the file.

Finally, if you used Turnitin directly, please change these settings in Turnitin:

In Assignment Settings, expand Optional Settings, then choose Generate Originality Reports for student submissions immediately (can overwrite until due date).