The difference between Daya duplicate checking and HowNet repetition rate is generally around 20%. This gap is mainly due to the difference of duplicate checking algorithm and comparison database between Daya and HowNet, which leads to some differences in duplicate checking results. In addition, books are the main content of Daya search, while HowNet covers a wider range of academic resources, including doctoral and master's dissertations. Therefore, Daya may miss some plagiarized doctoral theses, and HowNet can detect the plagiarized parts more comprehensively.

Daya and HowNet are two completely different duplicate checking softwares, and the test results can't be used as reference. When selecting the duplicate checking system, it should be selected according to the requirements of the school to ensure the accuracy and reference significance of the duplicate checking results. For the first draft of the paper, it is suggested that free duplicate checking software such as paperfree, papertime and paperday can be used. And for the final draft, use the duplicate checking system required by the school to ensure that the paper meets the requirements of academic norms.