Expectatlon and correlatlon 5.25 The joint PDF for two random variables fxx,(ri,T2) ?s given by Sketch...
Consider two random variables X and X2 with the joint pdf Nn.za) ={Orm ekewhere 1, o?r2 < 1 Let Y X,X2 and Y2X2 be a joint transformation of (Xi, X2) (a) Find the support of (Y.%) and sketch it. (b) Find the inverse transformation. (c) Compute the Jacobian of the inverse transformation (d) Compute the joint pdf of (Yi, Y2) (e) Derive the marginal pdf of Y? from the joint pdf of (y,,Y2).
The joint distribution function for two random variables X and Y is Fxx(x,y) = u(x) u(y)[1 - e-ax - e-av + e-a(x+y)], where a>0 Find and sketch the marginal pdf fyly)
Question 3 [17 marks] The random variables X and Y are continuous, with joint pdf 0 y otherwise ce fxx (,y) a) Show that cye fr (y) otherwise and hence that c = 1. What is this pdf called? (b) Compute E (Y) and var Y; (c) Show that { > 0 fx (a) e otherwise (d) Are X and Y independent? Give reasons; (e) Show that 1 E(XIY 2 and hence show that E (XY) =.
Question 3 [17...
2. (10 marks) Let X, and X, be two random variables with joint pdf 3.1 0 < x <3 <1; xix,( 22) - Yo elsewhere. a) Are X, and X, independent? If not, find E(X,X2). b) Are X, and X, correlated? Find Cou(X1, X2).
Random variables X and Y have joint PDF 2 0 otherwise. Compute the following. (a) Var[X] 08911 (b) Var[Y]-0.8911 (c) Cov[X,Y 6.2311 (d) Var [X+ Y]=14.24
Suppose X, Y are random variables whose joint PDF is given by . 1 0 < y < 1,0 < x < y y otherwise 0, 1. Find the covariance of X and Y. 2. Compute Var(X) and Var(Y). 3. Calculate p(X,Y).
4. Let X and Y be random variables of the continuous type having the joint pdf f(x,y) = 1, 0<x< /2,0 <y sin . (a) Draw a graph that illustrates the domain of this pdf. (b) Find the marginal pdf of X. (c) Find the marginal pdf of Y. (d) Compute plx. (e) Compute My. (f) Compute oz. (g) Compute oz. (h) Compute Cov(X,Y). (i) Compute p. 6) Determine the equation of the least squares regression line and draw it...
2. -30 a) The joint pdf of random variables X and Y is given by f(x,y) = 27ye-3 y<x<0, y >0. Show that the joint moment generating function(mgf) of X and Y is 27 M(t1, tz) = tı <3, tı + t, <3 (3 - tı) (3 - 7ı - t2) Use the joint mgf to obtain Cov(X,Y). b) Let X1, X2, X3 be independent random variables representing the lifetime of 3 electronic components with the following pdf, where X...
Consider the joint PDF of two random variables X and Y below. fx.y (x y) = 1, if 0 < x < 1, and 0 y< 1, and fxx (г, у) Oif andy are outside of that square. So, basically, the joint PDF is a constant over the unit square Let W X+Y. Suppose we express the CDF of W in the usual double integral form h Fw(W) 2 dy dx g where w-0.4 is a given value at which...
7. The joint pdf of two random variables X and Y is given by 0sxs3,0s y<5 fx(x,y) 15' 0, otherwise Find Cov(X,y)