Question

In: Statistics and Probability

Let W be a discrete random variable and Pr(W = k) = 1/6, k = 1,...

Let W be a discrete random variable and Pr(W = k) = 1/6, k = 1, 2 ,....., 6. Define
X =
{
W,  if W <= 3;
1,  if W >= 4;

}
and Y =
{
3,  if W <= 3;
7 -W,  if W >= 4;

}
(a) Find the joint probability mass function of (X, Y ) and compute Pr(X +Y = 4).
(b) Find the correlation Cor(X, Y ). Are X and Y independent? Explain.

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