争议的信息必须是收集起来代价昂贵并且具有时效性。

The information in question must be expensive to gather and time sensitive.

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最后，研究者们通过计算所有的使用者每天生存状态的平均“情感”分绘制了一系列的有时效性的情感地图。

Finally, the researchers calculated the average mood score of all the users living in a state hour by hour and so created a timed series of mood maps.

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但对于大多数国际罪行，是没有时效限制的。

For most international crimes, there is no time limit.

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It's also time-sensitive.

信息也有一定的时效性。

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