Reading Questions 7b

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Problem 1. 

(a) Suppose Cov(X,Y)0. Are X and Y independent?

 Yes
 No
  

(b) Suppose Cov(X,Y)=0 are X and Y independent?

 Yes
 No
 Maybe
  


Problem 2. 

Consider the following joint probability table.

(a) Are X and Y independent?

 Yes
 No
  

(b) What is Cov(X,Y)?

 -0.3
 -0.2
 -.1
 0
 0.1
 0.2
 0.3