The seasonal variation index (SVI) is used to fit the seasonal trend of power load.

季节变动指数(SVI)用来拟合电力负荷的季节性趋势。

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There is a wide variation around the index return which at the tail can be devastating.

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That same concept can be dropped into cataloging, where even in the old days, when librarians described books within the boundaries of a physical index card, great variation still occurred.

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The remaining 10% of funds that outperformed the index can be attributed to chance variation since they did not consistently outperform over several years.

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