youdao

youdao

不一会儿，看守开始打盹了。他的头越来越低，两个人都打起鼾来。

Presently the watcher began to nod; his head drooped lower and lower, both men began to snore now.

youdao

Depending on where the assets expected returns are and the assets' standard deviations, we can see that we might be able to do better than--have a lower variance than either asset.

根据资产的预期收益,以及收益的标准差，可以看到我们有更好的选择,这里的方差值比以上两种方案都要低。

耶鲁公开课 - 金融市场课程节选