There is a theorem that says:(adsbygoogle = window.adsbygoogle || []).push({});

"Let X and Y be random variables. If X ≤ Y, then E(X) ≤ E(Y)."

But I don't really understand the meaning of "X ≤ Y". What does it mean?

For example, if X takes on the values 0,1,2,3, and Y takes on the values -1,2,5. Is X ≤ Y??

Any help is appreciated!

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# If X ≤ Y, then E(X) ≤ E(Y)

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