It shows the standard deviation of the return on the portfolio as a function of the expected return on the portfolio.

它是投资组合的收益标准差,关于预期收益率的函数图像。

耶鲁公开课 - 金融市场课程节选

7% 77% is class average and the standard deviation was 17% so you can see where things lie. 50% is a pass.

7是平均水平，标准偏差是%,这就是事情所在，50%就及格。

麻省理工公开课 - 固态化学导论课程节选

And then I could also do a Gaussian one here, with the mean of and the standard deviation of volatility divided by 2.

然后我在这里再写一个高斯分布的函数，它的浮动值的平均值和,标准偏差值都除了2。

麻省理工公开课 - 计算机科学及编程导论课程节选

To calculate the expected utility of your wealth, you might also have to look at the expected return, or the geometric expected return, or the standard deviation.

要计算你财富的期望效用,你也许还要研究预期收益曲线,或几何预期收益率,或是标准差

耶鲁公开课 - 金融市场课程节选

Because the square root of 10,000 is 100, whatever the standard deviation of the portfolio is, you would divide it by 100 and it would become really small.

因为一万的平方根是一百，无论这个投资组合的标准差是多大，当除以100后就都变得很小很小了。

耶鲁公开课 - 金融市场课程节选

The standard deviation is the square root of the variance.

标准差是方差的平方根

耶鲁公开课 - 金融市场课程节选

You want to, for any given expected return, you want to minimize the standard deviation, so it's the left-most line and that means that everyone will be holding the same portfolio.

你希望，在期望收益固定的情况下，你肯定希望将标准差最小化，而这条线是最左边的线,这就意味着所有人,都愿意持有这样的投资组合。

耶鲁公开课 - 金融市场课程节选

So that's .16/100; so the standard deviation is .04.

那就是0.16/100,所以标准差等于0.04

耶鲁公开课 - 金融市场课程节选

Then, once we did that we could plug that into the formula that I gave you last time and get the standard deviation of the portfolio and the expected return on the portfolio.

再将估算出的数值代入到,上节课给你们的公式中,就能得到资产投资组合的标准差,和该投资组合的预期收益率

耶鲁公开课 - 金融市场课程节选

What is the standard deviation?

标准差是多少

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So, the optimal thing to do if you live in a world like this n is to get n as large possible and you can reduce the standard deviation of the portfolio very much and there's no cost in terms of expected return.

如果现实中也这样简单的话,那么你就尽量增大,这样就能让投资组合的标准差,就会大大降低,从预期收益率的角度来看,这样做的成本是零。

耶鲁公开课 - 金融市场课程节选

That's got the lowest possible standard deviation of expected return and that's 25% stocks and 75% bonds with this sample period.

这个组合预期回报的标准差最小,在这一点上，投资组合,由25%的股票和75%的债券构成。

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Let's suppose that all of them are the same-- they all have the same standard deviation.

我们假设这些资产的收益率标准差-,均相等。

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It could be normal, everything, that would be a Gaussian, where if you recall there was a mean, and a standard deviation, and most values were going to be close to the mean.

可能是正态分布，也就是高斯分布，只要有平均值和标准偏差值，你就可以进行调用，大部分的值都是集中在平均值附近的。

麻省理工公开课 - 计算机科学及编程导论课程节选

You could always find a portfolio that had a higher expected return for the same standard deviation.

你总是可以找到一个投资组合,具有较高的预期回报,而标准差不变。

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Number of policies doesn't affect the means but it affects that standard deviation, so it becomes very collapsed and this is the basic core idea of insurance.

保单的数量并不影响其均值,但是会影响其标准差,所以这条曲线非常陡峭,而这就是保险的核心原理

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You can't come up with a number to describe the twenty-five standard deviation event; it's just too large a number, I think, for any of us to really comprehend.

你根本无法想出一个数字,来描述这个偏离25倍标准差的事件,对我们普通人来说,这是个难以想象的天文数字

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What we want to do now is compute the mean and variance of the portfolio-- or the mean and standard deviation, since standard deviation is the square root of the variance-- for different combinations of the portfolios.

我们现在要做的是,计算这个投资组合的均值和方差-,或者均值和标准差，因为标准差的平方就等于方差-,这对任何投资组合都是一样的。

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