And when we're talking about the amplitude of the wave, we're talking about the deviation from that average level. So, if we define the average level as zero, you can have either a positive amplitude or a negative amplitude.

当我们讨论一个波的振幅时,我们说的是偏离平均位置的量,如果我们把平均位置,定义为零的话，那幅值不是,正的就是负的，有时候人们在。

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There have been just 50 occasions since 1973 when this ratio was greater than one standard deviation from that average, as it is now.

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Bullish sentiment is just slightly above one standard deviation from the historical average and bearish sentiment is within one standard deviation.

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Rather it is just one standard deviation away from its average, making the current reading atypical, but not an outlier.

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