Chapter 5

Question 1

When are two random variables said to be independent?

Answer 1

when p(x,y) = px(x) * py(y)
of f(x,y) = fx(x) * fy(y)

Question 2

What is Cov(X,Y)?

Answer 2

Cov(X,Y) = E(XY) - ux * uy

Question 3

What is Correlation coeficient?

Answer 3

Cov(X,Y) / (sigma x * sigma y)

Question 4

What is the E(X - Y)?

Answer 4

= E(X) - E(Y)

Question 5

What is the V(X - Y)?

Answer 5

= V(X) + V(Y)