来自《耶鲁大学开放课程：金融市场第7集第7集》

because the red line is just a smooth growth path

因为这条红线上涨得十分平稳
like nothing happens to it

就像没有任何事件冲击
and yet the stock market is going up and down all over the place.

而股市却是一直起起落落
It's a little bit like if you had a weather forecaster

这就有点像是有一个气象预报员
and this morning he says,

他今天早上预报说
I predict today that the low today will be -100o

预计今天最低温度为零下100度
and then two days later he says,

而过了两天又预报说
I predict that the low today will be +150o.

预计今天的最低气温将为150度
You would eventually start concluding

你立马就能得出
that this weather forecaster can't be trusted

这气象预报不可信的结论
because we never get to those temperatures.

因为这种气温我们从来都没有碰到过
That's sort of what the stock market is doing;

这和股票市场的行为有点相似