Suppose X∼Exp(λ) for some λ >0. Compute E(X) and Var(X).
C. (Theory) • Prove that if X Exp(x) for some > 0, ² = Var(x) = 1 / 2
Suppose that EX-EY-0, var(X) = var(Y) = 1, and corr(X,Y) = 0.5. (i) Compute E3X -2Y]; and (ii) var(3X - 2Y) (ii) Compute E[X2]
Suppose X ~ G P(Y >X) if r e R+ P(Y > X) if r E Z+ amma (r , λ), Y ~ Exp(A2) and X Y. Find: a) b) Suppose X ~ G P(Y >X) if r e R+ P(Y > X) if r E Z+ amma (r , λ), Y ~ Exp(A2) and X Y. Find: a) b)
Suppose X~N(1; 4) and Y = e^2X. Compute E[Y ] and Var(Y )
1. Suppose that Xi,..,Xn are independent Exponential random variables with density f(x; λ) λ exp(-1x) for x > 0 where λ > 0 is an unknown parameter (a) Show that the τ quantile of the Exponential distribution is F-1 (r)--X1 In(1-7) and give an approximation to Var(X(k)) for k/n-T. What happens to this variance as τ moves from 0 to 1? (b) The form of the quantile function in part (a) can be used to give a quantile-quantile (QQ) plot...
1. Suppose that Xi,..,Xn are independent Exponential random variables with density f(x; λ) λ exp(-1x) for x > 0 where λ > 0 is an unknown parameter (a) Show that the τ quantile of the Exponential distribution is F-1 (r)--X1 In(1-7) and give an approximation to Var(X(k)) for k/n-T. What happens to this variance as τ moves from 0 to 1? (b) The form of the quantile function in part (a) can be used to give a quantile-quantile (QQ) plot...
5. Let X ∼ Exp(λ) with λ unknown, and suppose X1, X2 is a random sample of size 2. Show that M = sqrt( X1 · X2 ) is a biased estimator of 1/λ and modify it to create an unbiased estimator. (Hint: During your journey, you’ll need the help of the gamma distribution, the gamma function, and the knowledge that Γ(1/2) = √ π.)
Let λ >0 and suppose that X1,X2,...,Xn be i.i.d. random variables with Xi∼Exp(λ). Find the PDF of X1+···+Xn. Use convolution formula and prove by induction
6. Suppose X and Y have the joint pdf fr,y) = 2 exp(-:- 0 ) 0< <y otherwise o a. Find Px.x, the correlation coefficient between X and Y. b. Let U = 2X-1 and V=Y +2. What is pu.v, the correlation coefficient between U and V? c. Repeat (b) if U = -TX and V = Y + In 2. d. Let W = Y - X. Compute Var (W). e. Refer to (d). Find an interval that will...
1. Suppose (x, Y) has bivariate normal distribution, E(x) E(Y)- 0, Var(X) σ , Var(Y) σ and Correl(X, Y) p. Calculate the conditional expectation E(X2|Y).