# joint density

1. ### Joint density distribution and Variance

Hi everyone! I was wondering if there is a way to calculate the joint distribution of two fully correlated variables, both with known distributions, expected value and variance, without knowing the conditional distribution? If this is not possible, is there a way of finding Var(X,Y) =...
2. ### integrating joint probability distribution

Hi, could you help me in compute the integral with respect to x of f(x,y)d(x,y) where f(x,y) is a joint probability distribution? I know that the integral with respect to x of f(x,y)dx is just f(y) where f(y) is the marginal distribution of y, but in the exercise I have f(x,y)d(x,y) inside the...
3. ### Joint density. Help!

Let x and y have the joint density: f(x,y) = 6/7(x+y)^2 for 0<=x<=1 and 0<=y<=1 a.Find the marginal densities of X and Y. . b.By integrating over the appropriate regions, find: i)P(X>Y) ii)P(X+Y)<=1 iii)P(x>=1/2) For this one, I got the answer for part(i). That is 1-P(X<=Y). but...
4. ### Joint and Marginal Densities.

I am having some problems grasping the concept of these joint and marginal densities. It would really help if someone could provide me with an answer for the following question: Find the joint and marginal densities corresponding to the cdf F(X, Y) = (1 - е^αx){1-e^βy), x > 0, y>0, α >...