Mathematica Can E(Y/S) Be Less Than 1 in IID Random Variables?

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In the discussion on whether E(Y/S) can be less than 1 for IID random variables S and Y, participants seek clarification on the mathematical properties of expected values. The main question revolves around demonstrating that E(Y/S) is greater than or equal to 1, given that S and Y are independent and identically distributed positive random variables with finite expected values. An example is requested where E(Y/X) equals positive infinity, prompting further exploration of the conditions under which expected values behave in this manner. The conversation highlights the need for understanding key results related to expected values and functions of random variables. Overall, the discussion emphasizes the complexities of expected values in the context of IID random variables.
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Mathematical Statistics~help please!

:cry:

Please help me with these question...

Let S and Y be i.i.d positive random variables with E(X)<infinity.
Show that E(Y/S) is greater or equal to 1. Give an example where

E(Y/X)=positive infinitiy...

I have no Idea where to begin...please help me..
 
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E(Y/S) = E(Y)(E1/S) since they are independent.What does it now boil down to showing? What results do you know that tell you when E(f(X)) > f(E(X)) for some function f?
 

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