How Do You Calculate Covariance and Correlation for X ~ U[0,1] and Y ~ U[0,X]?

Click For Summary
To calculate the covariance and correlation between X ~ U[0,1] and Y ~ U[0,X], one must apply the definitions of covariance and correlation. The covariance is given by Cov(X,Y) = E(XY) - E(X)E(Y). The expected values E(X) and E(Y) can be derived from their uniform distributions, while E(XY) requires integration over the joint distribution of X and Y. The discussion emphasizes the need to correctly evaluate these expected values to find the desired covariance and correlation. Understanding these concepts is crucial for solving the problem effectively.
asept
Messages
3
Reaction score
0
I'm stuck on this problem:

Let X be uniform[0,1] and Y be uniform[0,X]. Calculate the covariance and correlation between X and Y.


thanks
 
Physics news on Phys.org
Just apply the definition of covariance and correlation. What are the formulae for both?
 
Cov(X,Y) = E(XY) - E(X)E(Y)
 
Yes correct, and now just apply the formulae for E(X), E(Y) and E(XY). What formulae should you use to evaluate each?
 
Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

Similar threads

  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 5 ·
Replies
5
Views
2K
Replies
7
Views
2K
  • · Replies 3 ·
Replies
3
Views
2K
Replies
2
Views
2K
  • · Replies 14 ·
Replies
14
Views
2K
  • · Replies 7 ·
Replies
7
Views
2K
  • · Replies 3 ·
Replies
3
Views
2K
Replies
26
Views
2K
  • · Replies 13 ·
Replies
13
Views
2K