Question # 7. Let X and Y be independent Normal random variables witht he same vari- ance. Show t...
10. Let the random variables X ~ NGIX, σ%) and Y ~ Nuy,ơ be jointly continious normal random variables. Now suppose their joint pdf is X and Y are said to have a bivariate normal distribution (a) Given this joint pdf, show that X and Y are independent. (b) The most general form of the pdf for a bivariate normal distribution is What must be true about k for X and Y to be independent bivariate normal random variables? 10....
Let X1 and X2 be independent standard normal random vari ables, and let Y-AX-b, where Y-(y, Y)т, X-(X1, X2)T, b (1, -2) and (a) Determine the joint pdf of ı and Y2 by using the formula given in class for the joint pdf of Y = g(X) when X and Y are random vectors of the same dimension, and q is invertible with both g and its inverse differentiable (b) Show that the joint pdf in (a) can be expressed...
Suppose that X and Y are independent standard normal random variables. Show that U = }(X+Y) and V = 5(X-Y) are also independent standard normal random variables.
4. Let X and Y be independent standard normal random variables. The pair (X,Y) can be described in polar coordinates in terms of random variables R 2 0 and 0 e [0,27], so that X = R cos θ, Y = R sin θ. (a) (10 points) Show that θ is uniformly distributed in [0,2 and that R and 0 are independent. (b) (IO points) Show that R2 has an exponential distribution with parameter 1/2. , that R has the...
(Sums of normal random variables) Let X be independent random variables where XN N(2,5) and Y ~ N(5,9) (we use the notation N (?, ?. ) ). Let W 3X-2Y + 1. (a) Compute E(W) and Var(W) (b) It is known that the sum of independent normal distributions is n Compute P(W 6)
Let X and Y be independent binomial random variables B(n,p) on the same sample space. Show that X + Y is also a binomial random variable B(?,?). What values should replace the questions marks?
#2 : Let X and Y be independent standard normal random variables, let Z have an arbitrary density function, and form Q = (X+ZY)/(V1+ Z2). Prove that Q also has a standard normal density function
2. Let X and Y be independent, standard normal random variables. Find the joint pdf of U = 2X +Y and V = X-Y. Determine if U and V are independent. Justify.
2. Let X and Y are independent random variables with the same mass function f(-1) f(1) = 1/2. Let Z = XY. Show that X, Y, Z are pairwise independent but they are not independent. (Here、X,, . .. , xn are said to be pairwise independent if every pair Xi, X, with i f j are independent.)
Let X and Y be two independent random variables. Show that Cov (X, XY) = E(Y) Var(X).