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Turnitin’s support pages (as of July 2023) state that their detection system checks against GPT-3, GPT-3.5 and ChatGPT and that testing has been completed using other LLMs. It is entirely possible for a student to user use a variety of LLMs to refine a piece of work and Turnitin provide no reassurance for the reliability of their model when this approach is used. This is yet another reason to treat the AI detection score with caution.
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An AI detection score is accessible within the Originality Report window , for assignments submitted after 17th July 2023, to the new LTI Turnitin drop boxes. Historical assignments will not have this featureas shown below.
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When you click the AI detection score you will receive some more information about the text which has been matched as well as additional resources to help with any review.
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