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- 7. Suppose that the random variable X have the pdf f (x) = e-a*/2, x > 0 and 0 otherwise. 2T (a) Find E(X) and Var(X). (b) Find the transformation g(X)= Y and values of a and B such that Y ~ I(a, B).arrow_forwardSuppose X is a random variable and h is a non-increasing function, i.e., h(x1) #2. Please show that h(X) and h(-X) are negatively correlated, that is Cov[h(X), h(-X)] <0.arrow_forwardSuppose that the p.d.f. of X is as given f(x) = 3(1-x)2 for 0<x<1 and 0 otherwise Find the pdf of Y=(1-X)3 using the change of variable method.arrow_forward
- 7. Assume that X is a nonnegative, integer-valued random variable with p.g.f. G(z). Let G(¹) (z) denote the nth derivative of G. Let pk = P{X = k} for k = 0, 1, 2,.... Express each of the following as a function of G. (a) E[X]. (b) E[X(X - 1)]. (c) E[X(X - 1)(x - 2)]. (d) Var(X). (e) po. (f) P1. (g) Pn for n = 0, 1, 2,.... (h) Suppose an archer takes X shots at a target. Assume the shots are inde- pendent, and the archer hits the bullseye on any attempt with probability p. What is the probability that the archer is hits the bullseye on all X attempts? (i) Suppose the effective interest rate per period is i%. What is the present value of one dollar received at time X?arrow_forwardConsider that a pdf of a random variable X is 1 -25x53 fx (x) ={K otherwise and another random variable Y = 2X. Then find (a) value K, (b) E[X], (c) E[Y] and ( d) EΧΥ.arrow_forwardConsider a logistic regression system with two features x1 and x2. Suppose 00 = 5, 01 = 0, 02= 0, 03= -5, 04= -1, draw the decision boundary of hø(x) = g(0+ 01 x1+ 02 X2 + 03 xı²+ 04 x2?).arrow_forward
- (ii) Suppose that X₁ and X₂ have joint pdf 2, 10, Compute the joint pdf of random variables Y₁ = X₁ and Y₂ = X2. f(x1, x₂): for 0 < x1 < x₂ < 1 otherwise =arrow_forwardLet f(x) = Mean Value Theorem. x² and g(x) = xf(x). Find c € (0, 1) as guaranteed by the Cauchyarrow_forwardSuppose that Y is a continuous random variable. Show EY yfr(y)dy.arrow_forward
- There are only two states of the world, when a person is well with probability (1-p) and ill with probability p, where (1-p)= 1/3 and p = 2/3. Consider Adam who has utility function U = (Y1, Y2,1 – p,p) = Y,"-P)Y?, where Y; is the income and i =1 is well and i = 2 is ill. When Adam is well, he earns $1000, but when he is ill, he losses $300 in health expenditures and earnings such that Y2 = $700. What is the maximum total premium that Adam is still willing-to-pay? (1-р).arrow_forwardLet X1 and X2 be two independent random variables. Suppose each Xi is exponentially distributed with parameter λi. Let Y=Min (X1, X2). A) Find the pdf of Y. B) Find E(Y). Hint: Let Y = Min (X1, X2). 1. P[Y > c] = P[Min (X1, X2) > c] = P[X1 > c, X2 > c] 2. Obtain the pdf of Y by differentiating its cdf of Y.arrow_forwardAssume that a population of patients contains 30% of individuals who suffer from a certain fatal syndrome Z, which simultaneously makes it uncomfortable for them to take a life-prolonging drug X. Let Z = 1 and Z = 0 represent, respectively, the presence and absence of the syndrome, Y = 1 and Y = 0 represent death and survival, respectively, and X = 1 and X = 0 represent taking and not taking the drug. Assume that patients not carrying the syndrome, Z = 0, die with probability 0.5 if they take the drug and with probability 0.5 if they do not. Patients carrying the syndrome, Z = 1, on the other hand, die with probability 0.7 if they do not take the drug and with probability 0.3 if they do take the drug. Further, patients having the syndrome are more likely to avoid the drug, with probabilities p(X = 1|Z=0) = 0.9 and P(X = 1|Z = 1) = 0.6 . Based on this model, compute the joint distributions and for all values of x, y, and z. Present the following joint distributions in tables. [Hint:…arrow_forward
- Algebra & Trigonometry with Analytic GeometryAlgebraISBN:9781133382119Author:SwokowskiPublisher:CengageLinear Algebra: A Modern IntroductionAlgebraISBN:9781285463247Author:David PoolePublisher:Cengage Learning