So we can get the best estimator of the true variance.
所以我们可以获得真实方差的最佳估计量。
True variance
原声例句
可汗学院：统计学（视频版）
可汗学院：统计学（视频版）
If we magically knew the distribution, there's some true variance here.
如果我们神奇地知道分布，这里就有一些真正的差异。
中文百科
方差 Variance
（重定向自True variance）
方差（Variance），应用数学里的专有名词。在概率论和统计学中，一个随机变量的方差描述的是它的离散程度，也就是该变量离其期望值的距离。一个实随机变量的方差也称为它的二阶矩或二阶中心动差，恰巧也是它的二阶累积量。方差的算术平方根称为该随机变量的标准差。
英语百科
Variance 方差
（重定向自True variance）
In probability theory and statistics, variance is the expectation of the squared deviation of a random variable from its mean, and it informally measures how far a set of (random) numbers are spread out from their mean. The variance has a central role in statistics. It is used in descriptive statistics, Statistical inference, hypothesis testing, goodness of fit, Monte Carlo sampling, amongst many others. This makes it a central quantity in numerous fields such as Physics, Biology, Chemistry, Economics, and Finance. The variance is the square of the standard deviation, the second central moment of a distribution, and the covariance of the random variable with itself, and it is often represented by σ² or Var(X).