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第280行： − 重要限制条件+ 第315行：
第315行： − 对于大多数其他网络节点，排名可能是没有意义的。这就解释了为什么，例如，只有谷歌图片搜索的前几个结果以合理的顺序出现。Pagerank 是一个非常不稳定的度量，显示了在跳转参数小的调整之后频繁的秩逆转。+
→Important limitations
== Important limitations ==
== Important limitations ==
重要限制
Centrality indices have two important limitations, one obvious and the other subtle. The obvious limitation is that a centrality which is optimal for one application is often sub-optimal for a different application. Indeed, if this were not so, we would not need so many different centralities. An illustration of this phenomenon is provided by the [[Krackhardt kite graph]], for which three different notions of centrality give three different choices of the most central vertex.<ref>{{cite journal|title=Assessing the Political Landscape: Structure, Cognition, and Power in Organizations|first=David|last=Krackhardt|authorlink=David Krackhardt|journal=Administrative Science Quarterly|volume=35|issue=2|date=June 1990|pages=342–369|doi=10.2307/2393394|jstor=2393394}}</ref>
Centrality indices have two important limitations, one obvious and the other subtle. The obvious limitation is that a centrality which is optimal for one application is often sub-optimal for a different application. Indeed, if this were not so, we would not need so many different centralities. An illustration of this phenomenon is provided by the [[Krackhardt kite graph]], for which three different notions of centrality give three different choices of the most central vertex.<ref>{{cite journal|title=Assessing the Political Landscape: Structure, Cognition, and Power in Organizations|first=David|last=Krackhardt|authorlink=David Krackhardt|journal=Administrative Science Quarterly|volume=35|issue=2|date=June 1990|pages=342–369|doi=10.2307/2393394|jstor=2393394}}</ref>
For the majority of other network nodes the rankings may be meaningless. This explains why, for example, only the first few results of a Google image search appear in a reasonable order. The pagerank is a highly unstable measure, showing frequent rank reversals after small adjustments of the jump parameter.
For the majority of other network nodes the rankings may be meaningless. This explains why, for example, only the first few results of a Google image search appear in a reasonable order. The pagerank is a highly unstable measure, showing frequent rank reversals after small adjustments of the jump parameter.
对于大多数其他网络节点，排名可能是没有意义的。这就解释了为什么，例如，只有谷歌图片搜索的前几个结果以合理的顺序出现。Pagerank（网页排名） 是一个非常不稳定的度量，显示了在跳转参数小的调整之后频繁的秩逆转。