Markowitz's mean variance model describes the risk of asset by variance, but variance may not exist because of fat tailedness of asset returns.

马柯维兹均值—方差模型使用收益率的方差度量证券的风险，但是实际分布呈尖顶胖尾状，使得方差可能不存在。

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The results indicate that the initial deviations of the joint positions match normal probability density function limited in the range of double mean variance.

随机缺陷分析方法中假定结构每个节点的位置偏差符合二倍均方差范围内的正态概率密度函数是可以接受的。

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The proposed method analyses local image statistics and then matches the local histograms of two images to be fused by applying mean or mean variance matching normalization functions.

该方法分析了局部影像统计特性，应用均值或均值—方差匹配正态函数，对要融合的两幅影像局部直方图进行匹配。

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What we did--the core theoretical framework that we had-- was the mean variance theory, which led us to the capital asset pricing model.

我们讲到了投资组合多元化的核心理论框架,即均值-方差模型,之后又讲到了资本资产定价模型

耶鲁公开课 - 金融市场课程节选

In fact, I have it--suppose we have three assets and we want to compute the efficient portfolio frontier, the mean and variance of the portfolio.

事实上，假如我们拥有三种资产,我们想计算有效边界，及投资组合的均值和方差。

耶鲁公开课 - 金融市场课程节选

But, in between, if some other number, it'll be some blend of the--mean and variance of--the portfolio will be some blend of the mean and variance of the two assets.

但如果是在0和1之间的其他数值，这个投资组合的均值和方差将会是,两项资产各自的均值和方差的综合结果。

耶鲁公开课 - 金融市场课程节选