Let X and Y have the joint pmf defined by (х, у) (1,2) (0,0) (0,1) (0,2)...
Let the joint pmf of X and Y be defined by x+y 32 x 1,2, y,2,3,4 (a) Find fx(x), the marginal pmf of X. b) Find fyv), the marginal pmf of Y (c) Find P(XsY. (d) Find P(Y 2x). (e) Find P(X+ Y 3) (f) Find PX s3-Y) (g) Are Xand Y independent or dependent?Why or why not? (h) Find the means and the variances of X and Y
Let the joint pmf of X and Y be p(x, у) схуг, x-1,2,3, y-12. a) Find constant c that makes p(x, y) a valid joint pmf. c) Are X and Y independent? Justify d) Find P(X+Y> 3) and PCIX-YI # 1)
The joint pmf of X and Y is defined by f(x,y)=, x=1,2; y=1,2 (a) Find Cov(X,Y). (b)Find E(X|Y=1) x + 2y 18
Question 6: (5 marks). Let (X, Y) have the joint probability function (2r y)/15, r=1,2,3;y 1,2; otherwise Px.y (r, y) 0, Find pxy (y)
We have the following joint PMF of X and Y: Pxy (x,y) ſa(x+3y) x =1,2,3; y =1,2 0 otherwise Find: 1. the value of a 2. the marginal PMFs of X and Y 3. if X and Y are independent
4.2 The Correlation Coefficient 1. Let the random variables X and Y have the joint PMF of the form x + y , x= 1,2, y = 1,2,3. p(x,y) = 21 They satisfy 11 12 Mx = 16 of = 12 of = 212 2 My = 27 Find the covariance Cov(X,Y) and the correlation coefficient p. Are X and Y independent or dependent?
Suppose that X and Y have joint pmf px yx,y) fxy-/39 for x 1,2 and y 2,3 0elsewhere). a) Determine the marginal pmfs px(x) and py(y) b) Determine the conditional pmf of px(xly). c) Are X and Y independent? Give a clear determination using probability formulas.
Table 1 Joint PMF of X and Y in Example 5.1 x=01 X=1 | 1 Fig. 1 shows PXY()PXY( JointPMF ? 2 Fig. 1. Joint PMF of X and Y (Example 5.1). a. b. c. d. Find P(X-0,Y<1). Find the marginal PMFs of X and Y. Find P(Y-1X-0). Are X and Y independent?
ciule jolh! PMF and the marginal PMFs? 6.14 Let X and Y be discrete random variables. Show that the function p: R2 R defined by p(r, y) px(x)pr(y) is a joint PMF by verifying that it satisfies properties (a)-(c) of Proposition 6.1 on page 262. Hint: A subset of a countable set is countable CHAPTER SIX Joindy Discrete Random Variables 6.2 Joint and marginal PMFs of the discrete random variables x numher of bedrooms and momber of bwthrooms of a...
(C\x + y| х % - 2,0,2 y =1,0,1 otherwise 3. Xand Y are two RVs whose joint PMF are given on the right: -17 Рxr(x, у) %3D What is the value of constant C ? а. b. What is P [X> Y] ? What is P [Ys 0]? d. For a new RV W=2X+Y, What is the PMF P/(w)? е. P[W>1] с.