SOLUTION: Let X and Y represent continuous random variables. Let {{{f(x,y)=(xy/4)}}} For -1 < x < 1 and −1 < y < 1 and 0 otherwise. Can f(x,y) be a joint density function for X and Y.

Question 1136604: Let X and Y represent continuous random variables. Let
For -1 < x < 1 and −1 < y < 1 and 0 otherwise.
Can f(x,y) be a joint density function for X and Y. If so, explain why. If not, explain why not.
Answer by ikleyn(52847) (Show Source): You can put this solution on YOUR website!
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Density function, by the definition, is non-negative over its domain.


The given function f(x,y) is negative in QII and in QIV.


Therefore, it CAN NOT be a density function.

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