I should be able to do nice bell-shaped curves, but it's harder than it looks standing up here; so that's your bell-shaped curve.

我还是挺擅长画钟型曲线的,但站着画真的不太容易,这就是钟型曲线

耶鲁公开课 - 金融市场课程节选

But I want to emphasize that there are also other bell-shaped curves.

但我想强调的是,还存在别的钟形曲线

耶鲁公开课 - 金融市场课程节选