Let X and Y be two random variables.(adsbygoogle = window.adsbygoogle || []).push({});

Say, for example, they have the following joint probability mass function

What is the proper way of computing E(XY)?Code (Text):

x

-1 0 1

-1 0 1/4 0

y 0 1/4 0 1/4

1 0 1/4 0

Can I let Z=XY and find E(Z)=∑ z P(Z=z) ? Would this give E(XY)?

Thanks for explaining!

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# Expectation of 2 random variables

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