(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Hi all.

Lets say I have two variables y_{k}and x_{k}. I also have two mean values given by:

[tex]

<y_k^2> = \frac{1}{N}\sum_1^N{y_k^2} \quad \text{and} \quad <x_k^4> = \frac{1}{N}\sum_1^N{x_k^4}.

[/tex]

Now I am looking at the expression (<x_{k}^{4}> <y_{k}^{2}>)^{1/2}.

Question: Is it correct that:

[tex]

<y_kx_k^2> = \sqrt{<x_k^4><y_k^2>}.

[/tex]

Personally, I don't think so, because ultimately it would mean that I would have to make two sums into one sum, which I can't.. but I am in doubt.

Thanks in advance.

Niles.

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# Statistics: Mean values

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