We study how a single paper affects the Impact Factor (IF) by analyzing data from 3,088,511 papers published in 11639 journals in the 2017 Journal Citation Reports of Clarivate Analytics. We find that IFs are highly volatile. For example, the top-cited paper of 381 journals caused their IF to increase by more than 0.5 points, while for 818 journals the relative increase exceeded 25%. And one in 10 journals had their IF boosted by more than 50% by their top three cited papers. Because the single-paper effect on the IF is inversely proportional to journal size, small journals are rewarded much more strongly than large journals for a highly-cited paper, while they are penalized more for a low-cited paper, especially if their IF is high. This skewed reward mechanism incentivizes high-IF journals to stay small, to remain competitive in rankings. We discuss the implications for breakthrough papers appearing in prestigious journals. We question the reliability of IF rankings given the high IF sensitivity to a few papers for thousands of journals.

中文翻译：

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单篇论文的影响因子波动率：综合分析

我们通过分析 2017 年科睿唯安期刊引证报告中 11639 种期刊发表的 3,088,511 篇论文的数据，研究了一篇论文如何影响影响因子 (IF)。我们发现 IF 的波动性很大。例如，381个期刊的高被引论文导致其IF上升超过0.5分，而818个期刊的相对上升幅度超过25%。十分之一的期刊的 IF 被前三篇引用的论文提高了 50% 以上。由于单篇论文对 IF 的影响与期刊大小成反比，因此小型期刊在高被引论文中比大型期刊获得的奖励要强得多，而在低被引论文中受到的惩罚更多，尤其是当它们的 IF 为高的。这种倾斜的奖励机制激励高 IF 期刊保持规模较小，以保持排名竞争力。我们讨论了出现在著名期刊上的突破性论文的影响。鉴于对数千种期刊的几篇论文的高 IF 敏感性，我们质疑 IF 排名的可靠性。