H-index 又稱為h指數或h因子（h-factor）, 一名科研人員的h指數是指他至多有h篇論文分別被引用了至少h次。
例如，某人的h指數是20，這表示他已發表的論文中，每篇被引用了至少20次的論文總共有20篇。
這是一種評價學術成就的新方法。一個人的h指數越高，則表明他的論文影響力越大。
但是 h指數就像某個期刊的影響因子一樣，不適合用於跨學科的比較。
以下是查詢某個學者的h-index的3種方法：
1. web of science
2. scopus
3. google scholar
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This is the English version:
H-index, also known as h-factor.
One's h-index is x means that at most x of all his or her papers are cited at least x times.
For example, Andy has an h-index of 20 means that among all his published papers, there are 20 papers cited at least 20 times.
It is a way to evaluate one's academic achievement. An higher h-index means the greater effect of papers.
However, just similar with the impact factor of journals, it is not suitable for cross-disciplinary comparison.
Here are three ways to search the researchers' h-index below:
1. web of science
2. scopus
3. google scholar