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PolyU Library

Citation & Avoiding Plagiarism

A quick guide to reach library resources and tools for academic integrity

Available Plagiarism Checking Tools

Text similarity-checking tools can assist in detecting potential plagiarism. Each tool will check against a collection of papers and webpages from their underlying database. Different tools may serve different purposes and audiences. PolyU has subscribed to Turnitin for checking student works and VeriGuide for checking academic papers and grant applications.

Here is a quick comparison of available plagiarism-checking tools: 

Tools Target for How to access Guides

Turnitin-LTI

Checking student assignments & theses

**Detecting AI-generated texts is now available

via Turnitin-LTI assignment on Learn@PolyU

For technical support, please contact ITS.

Student Guide
Instructor Guide

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VeriGuide

Checking academic papers & grant applications 

(It supports similarity text detection in English, Traditional Chinese, and Simplified Chinese.)

PolyU Research & Innovation Office subscribed to the "VeriGuide" service to support research activities for academic staff and other authorised users.

Research and Innovation Office - VeriGuide

iThenticate

Checking academic papers; used by major publishers

PolyU does not have a subscription. Users need to subscribe/ buy credits via its website. Getting started

Apart from these, some online plagiarism checking tools and AI detector tools are listed here. Do check with your instructor or supervisor if it is acceptable to use any of the tools to check your work.

Plagiarism checking tools

AI detector tools

Student FAQs on Plagiarism Checking and using Turnitin

1. Can I self-check my work using other online plagiarism checkers and AI detection tools OR in Turnitin for similarity checking before submitting it to the Turnitin assignment?

The Similarity Report from Turnitin compares your submission text against selected search targets or databases. While some online plagiarism checkers and AI detection tools are listed in this Plagiarism Checking Tools Guide, they have different search targets and cannot replace Turnitin.

If you want to check a paper in Turnitin before submitting it to an assignment, contact your instructor to see if resubmissions are allowed or not (see FAQ no. 2) . 


2. Can I resubmit my work to get a new similarity report?

It depends on whether resubmission has been enabled by your instructor.

  • If resubmissions are not allowed, your first submission will be final.
  • If resubmissions are permitted, you can submit multiple times before the due date, with each new submission overwriting the previous one.

You will need to wait around 30 - 60 minutes to get a new similarity report for initial submissions and the first 3 resubmissions. For the 4th and subsequent resubmissions, Similarity Reports will require at least 24 hours to process. 
For details, please refer to the Student Guide - Quick Student Guide to Using Turnitin LTI Assignment with LEARN@PolyU (P.8).


3. How can I create an account in Turnitin?

As a student, you will not be able to create an account - your instructor will create a Turnitin assignment link for you to submit your assignment. The link will be available on the course page in Learn@PolyU(理學網). 

Steps to submit an assignment to Turnitin: Student Guide - Quick Student Guide to Using Turnitin LTI Assignment with LEARN@PolyU.
For technical support on Turnitin, please contact ITS Blackboard Support at 2766 5900 or through IT Online ServiceDesk.

4. How can I check the similarity of my thesis in Turnitin?

You may check the similarity rate for your thesis in Turnitin, but you will need to seek your supervisor's help to create a Turnitin assignment for you. The link can be embedded in a course that is designated for checking students' works. For technical details, please check with ITS Blackboard Support at 2766 5900 or through IT Online ServiceDesk.


5. How can I check the similarity of my journal article in Turnitin?

Turnitin is mainly for checking student assignments. To check journal articles, VeriGuide will be a better choice since it covers scholarly journal articles and free internet resources. Since VeriGuide is limited to PolyU academic staff only, please seek your supervisor's help to have your article (most likely co-authored with your supervisor) checked on VeriGuide. Alternatively, you may also subscribe iThenticate and check your work there. 


6. What % of similarity is safe?

There’s no official answer. All plagiarism-checking tools are text-matching tools and are not able to determine intent. They do not grade papers for instructors; instead, instructors will judge the papers based on information provided in the similarity report.

Always focus on making sure proper acknowledgement is made instead of reducing the text similarity!


7. I resubmitted my work to another Turnitin assignment and received a very high similarity index. What should I do?

First of all, it is not ethical to submit the same work to two different assignments. If you wish to check the similarity of a revised version, you need to resubmit via the same Turnitin assignment portal. 

If you have submitted the work to two different assignments and wish to keep the latest submission, you may seek your instructor's help to delete the original submission from their database. Your instructor should contact the Turnitin administrator (which is ITS) and provide them with the class ID, paper ID, and assignment name. ITS colleagues will then request the Turnitin Support Team to remove the submission.


8. Can I exclude references in the similarity report?

As a student, you can exclude references by applying the “Exclude quotes and bibliography” filter. However, any exclusions you make are temporary and won't affect your official similarity score (i.e. instructor’s view). If you believe certain exclusions should be made to adjust your score officially, please contact your instructor.


9. Does Turnitin offer a solution to detect AI writing?

Turnitin has added an AI writing indicator to the Similarity Report. It shows an overall percentage of the document that AI writing tools, such as ChatGPT, may have generated. The indicator further links to a report which highlights the text segments that our model predicts were written by AI.

For more details, please visit Turnitin's AI writing detection capabilities FAQs.


For more information about Plagiarism Detection and Turnitin-LTI Assignments, please visit the ITS page.