The rapid growth results from the fact that the majority of the people fall into the middle of a left-skewed bell-shaped curve.

之所以迅速增长，是因为大多数人都陷入了左弯的钟形曲线的中间。

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3 For many random variables, a good choice is the normal distribution, often represented as a bell-shaped curve, shown in Figure 1.

3对于许多随机变量来说，一个好的选择是正态分布，常常表现为一个钟型曲线，如图1所示。

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So it seems there is a bell-shaped curve where small amounts are signaling and very beneficial, while large amounts are damaging and very hurtful.

因此，似乎存在一个钟形曲线，少量是发出信号和非常有益的，而大量是破坏性和非常有害的。

youdao

It's a bell-shaped curve that looks about like that.

大概就是一条这样的钟形曲线

耶鲁公开课 - 金融市场课程节选

That's a bell-shaped curve, but it's centered exactly on .2.

这是条钟形曲线,它关于x=0.2对称

耶鲁公开课 - 金融市场课程节选

Imagine a society that has a bell-shaped income distribution curve with a broad middle class, a smaller number of rich and poor, and an even smaller number of super rich and super poor.

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Poll investors, amateur or professional, about the future and you will likely get a neatly-shaped bell curve of expected outcomes, with most respondents herding toward the perceived safety of the middle ground.

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The other problem is that having sufficient data to draw a proper curve, bell shaped or otherwise.

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