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$Y = \Sigma^{-1/2}(X-\mu )$ with $\Sigma$ being the covariance matrix and $\mu$ the sample mean.

What is the intuition behind this calculation? What kind of result does it yield?

This calculation is used in various estimates for multivariate Skewness.

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    $\begingroup$ It's the multivariate generalization of standardization, q.v. $\endgroup$
    – whuber
    Commented May 13, 2017 at 21:43

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As there is no information regarding the distribution of the random vector $X$, I assume that $$X\sim N_{p}(\mu,\Sigma),\qquad \Sigma >0.$$

The matrix $\Sigma^{-1/2}$ is the symmetric positive definite square root of $\Sigma$.

The transformation $Y=\Sigma^{-1/2}(X-\mu)$, results in a random vector whose components are independent and each is an univariate $N_{1}(0,1)$ random variable. In other words, the random vector $Y$ contains independent and identically distributed $N_{1}(0,1)$ random variables.

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