The coincidence degree of papers is the similarity or coincidence degree of academic papers in content, which is usually used to detect whether the papers are plagiarized. Generally, colleges and universities define the coincidence degree of more than 30% as plagiarism, that is, the paper failed to pass the examination.

First of all, whether the quoted words are plagiarized or not has nothing to do with marking the source. These all depend on the threshold of the system. The sensitivity of this detection system is set to a threshold of 3%. In terms of the number of words in a paragraph (or chapter), plagiarism or citation of a single document below 3% cannot be detected.

For example, if the detection paragraph 1 (chapter 1) has 10000 words, if A document is cited, it will not be detected within 300 words (10000 times 3%=300). If more than 300 words are quoted from the B document, the plagiarism of the B document distributed in the first chapter will be marked in red, no matter where it is located in the first chapter, even if it is interrupted into a sentence, as long as it exceeds 20 words, it will be marked.

"College Students' Paper Plagiarism Detection System" (PMLC for short) is independently developed by Tsinghua Tongfangzhiwang. The plagiarism detection system for college students' papers (PMLC) was officially released on August 20 10. It will be fully applied to the daily teaching of colleges and universities to help colleges and universities check whether there is plagiarism in students' papers and homework.