摘要：所谓事后认定，比如，《北京大学学报》，如何认定，若按2018-2020期间该刊所刊用论文为基础认定，就只能承认该刊在2018-2020年为C刊。至于能否在2021-2022年算C刊，则需要看2021-2022年所刊发论文的质量。不能以2018年-2020年所刊
宋圭武：建议C刊采取事后认定办法
论文质量认定，一般大都以C刊为主。如何认定C刊，个人建议C刊应采取事后认定办法。
所谓事后认定，比如，《北京大学学报》，如何认定，若按2018-2020期间该刊所刊用论文为基础认定，就只能承认该刊在2018-2020年为C刊。至于能否在2021-2022年算C刊，则需要看2021-2022年所刊发论文的质量。不能以2018年-2020年所刊发论文为基础，认定2021-2022年该刊为C刊。这是一种认定错位。
在事后认定的情况下，所有期刊，事实上只能在认定的年限内算C刊，在认定的年限以后，所有期刊都是平等的，都不存在C刊一说。至于认定年限以后一个刊物能否算C刊，则要依据认定年限以后该刊所刊用论文情况而定。
事后认定的好处是：一是有利于督促编辑更倾向于采用高质量论文；二是有利于刊物之间公平竞争；三是有利于大学减轻研究生发表论文压力；四是有利于督促作者进一步提高论文质量；五是有利于更科学评价论文质量。
Song Guiwu: It is suggested that Journal C adopts the ex post facto recognition method
The quality of papers is generally mainly based on Journal C.How to recognize Journal C, personally, I suggest that Journal C should adopt the ex post facto recognition method. The so-called ex post facto recognition, for example, the Journal of Peking University, how to recognize, if according to the papers published by the journal during 2018-2020, it can only be recognized as Journal C in 2018-2020.As for whether it can be calculated as Journal C in 2021-2022, it needs to see the quality of the papers published in 2021-2022.It can not be based on the papers published in 2018-2020 to recognize the journal as Journal C in 2021-2022.This is a kind of recognition dislocation. In the case of ex post facto recognition, all journals can only be calculated as Journal C within the recognized years. After the recognized years, all journals are equal, and there is no Journal C.As for whether a journal can be calculated as Journal C after the recognized years, it depends on the papers published by the journal after the recognized years. The advantages of ex post facto recognition are: first, it is conducive to urging editors to adopt high-quality papers;second, it is conducive to fair competition between journals;third, it is conducive to reducing the pressure of graduate students to publish papers;fourth, it is conducive to urging authors to further improve the quality of papers;fifth, it is conducive to more scientific evaluation of the quality of papers.
来源：宋圭武