Mathematical Statistics with Applications
7th Edition
ISBN: 9780495110811
Author: Dennis Wackerly, William Mendenhall, Richard L. Scheaffer
Publisher: Cengage Learning
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Question
Chapter 9.5, Problem 68E
To determine
Prove that if the family of the density
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4. Let X, Y be non-negative continuous random variables with probability density functions (pdf) gx(x)
and gy (y), respectively. Further, let f(x, y) denote their joint pdf. We say that X and Y are independent
if f(x, y) = 9x(x)hy (y) for all x, y ≥ 0.
Further, we define the expectation of X to be
E[X] = √rg(x)dx,
to be the expectation of XY.
0
with a similar definition for Y but g replaced by h and x replaced by y. We also define
E[XY] = (0,00)x (0,00)
110,00)x (0,00) 29 (x, y) dedy
(0,∞)
Use Fubini's theorem (which you may assume holds) to show that if X and Y are independent, then
E[XY] = E[X]E[Y].
[2]
4. Let X, Y be non-negative continuous random variables with probability density functions (pdf) gx(x)
and gy (y), respectively. Further, let f(x, y) denote their joint pdf. We say that X and Y are independent
if f(x, y) = gx (x)hy (y) for all x, y ≥ 0.
Further, we define the expectation of X to be
- 1.²0⁰
with a similar definition for Y but g replaced by h and x replaced by y. We also define
to be the expectation of XY.
E[X] =
xg(x) dx,
E(XY)= (0,00)x(0,00) Tuf(x,y)dady
(0,∞) (0,∞)
Use Fubini's theorem (which you may assume holds) to show that if X and Y are independent, then
E[XY] = E[X]E[Y].
Let f, g be probability densities such supp(f) c supp(g). show yes
X1, ... , Xn
X1,..., X, iid.
L(g)
then
f(X;)
W; =
g(X;)
is hopeful 1. Argue why the weights need to be re-normalized even
when the normalization constants of the densities f and g are known.
Chapter 9 Solutions
Mathematical Statistics with Applications
Ch. 9.2 - Prob. 1ECh. 9.2 - Let Y1, Y2,, Yn denote a random sample from a...Ch. 9.2 - Let Y1, Y2, , Yn denote a random sample from the...Ch. 9.2 - Let Y1, Y2, , Yn denote a random sample of size n...Ch. 9.2 - Suppose that Y1, Y2, , Yn is a random sample from...Ch. 9.2 - Prob. 6ECh. 9.2 - Prob. 7ECh. 9.2 - Let Y1, Y2, , Yn denote a random sample from a...Ch. 9.3 - Applet Exercise How was Figure 9.1 obtained?...Ch. 9.3 - Applet Exercise Refer to Exercise 9.9. Scroll down...
Ch. 9.3 - Applet Exercise Refer to Exercises 9.9 and 9.10....Ch. 9.3 - Applet Exercise Refer to Exercise 9.11. What...Ch. 9.3 - Applet Exercise Refer to Exercises 9.99.12. Access...Ch. 9.3 - Applet Exercise Refer to Exercise 9.13. Scroll...Ch. 9.3 - Refer to Exercise 9.3. Show that both 1 and 2 are...Ch. 9.3 - Refer to Exercise 9.5. Is 22 a consistent...Ch. 9.3 - Suppose that X1, X2,, Xn and Y1, Y2,,Yn are...Ch. 9.3 - In Exercise 9.17, suppose that the populations are...Ch. 9.3 - Let Y1, Y2,,Yn denote a random sample from the...Ch. 9.3 - If Y has a binomial distribution with n trials and...Ch. 9.3 - Let Y1, Y2,, Yn be a random sample of size n from...Ch. 9.3 - Refer to Exercise 9.21. Suppose that Y1, Y2,, Yn...Ch. 9.3 - Refer to Exercise 9.21. Suppose that Y1, Y2,, Yn...Ch. 9.3 - Let Y1, Y2, Y3, Yn be independent standard normal...Ch. 9.3 - Suppose that Y1, Y2, , Yn denote a random sample...Ch. 9.3 - Prob. 26ECh. 9.3 - Use the method described in Exercise 9.26 to show...Ch. 9.3 - Let Y1, Y2, , Yn denote a random sample of size n...Ch. 9.3 - Let Y1, Y2, , Yn denote a random sample of size n...Ch. 9.3 - Let Y1, Y2, , Yn be independent random variables,...Ch. 9.3 - Prob. 31ECh. 9.3 - Let Y1, Y2, , Yn denote a random sample from the...Ch. 9.3 - An experimenter wishes to compare the numbers of...Ch. 9.3 - Prob. 34ECh. 9.3 - Let Y1, Y2, be a sequence of random variables with...Ch. 9.3 - Suppose that Y has a binomial distribution based...Ch. 9.4 - Prob. 37ECh. 9.4 - Let Y1, Y2, , Yn denote a random sample from a...Ch. 9.4 - Let Y1, Y2, , Yn denote a random sample from a...Ch. 9.4 - Prob. 40ECh. 9.4 - Let Y1, Y2, , Yn denote a random sample from a...Ch. 9.4 - If Y1, Y2, , Yn denote a random sample from a...Ch. 9.4 - Prob. 43ECh. 9.4 - Let Y1, Y2, , Yn denote independent and...Ch. 9.4 - Suppose that Y1, Y2, , Yn is a random sample from...Ch. 9.4 - If Y1, Y2,, Yn denote a random sample from an...Ch. 9.4 - Refer to Exercise 9.43. If is known, show that...Ch. 9.4 - Refer to Exercise 9.44. If is known, show that...Ch. 9.4 - Let Y1, Y2, . . . , Yn denote a random sample from...Ch. 9.4 - Let Y1, Y2, . . . , Yn denote a random sample from...Ch. 9.4 - Prob. 51ECh. 9.4 - Prob. 52ECh. 9.4 - Prob. 53ECh. 9.4 - Prob. 54ECh. 9.4 - Let Y1, Y2, . . . , Yn denote independent and...Ch. 9.5 - Refer to Exercise 9.38(b). Find an MVUE of 2. 9.38...Ch. 9.5 - Refer to Exercise 9.18. Is the estimator of 2...Ch. 9.5 - Refer to Exercise 9.40. Use i=1nYi2 to find an...Ch. 9.5 - The number of breakdowns Y per day for a certain...Ch. 9.5 - Prob. 60ECh. 9.5 - Refer to Exercise 9.49. Use Y(n) to find an MVUE...Ch. 9.5 - Refer to Exercise 9.51. Find a function of Y(1)...Ch. 9.5 - Prob. 63ECh. 9.5 - Let Y1, Y2, , Yn be a random sample from a normal...Ch. 9.5 - In this exercise, we illustrate the direct use of...Ch. 9.5 - The likelihood function L(y1,y2,,yn|) takes on...Ch. 9.5 - Refer to Exercise 9.66. Suppose that a sample of...Ch. 9.5 - Prob. 68ECh. 9.6 - Prob. 69ECh. 9.6 - Suppose that Y1, Y2, , Yn constitute a random...Ch. 9.6 - If Y1, Y2, , Yn denote a random sample from the...Ch. 9.6 - If Y1, Y2, , Yn denote a random sample from the...Ch. 9.6 - An urn contains black balls and N white balls....Ch. 9.6 - Let Y1, Y2,, Yn constitute a random sample from...Ch. 9.6 - Prob. 75ECh. 9.6 - Let X1, X2, X3, be independent Bernoulli random...Ch. 9.6 - Let Y1, Y2,, Yn denote independent and identically...Ch. 9.6 - Let Y1, Y2,, Yn denote independent and identically...Ch. 9.6 - Let Y1, Y2,, Yn denote independent and identically...Ch. 9.7 - Suppose that Y1, Y2,, Yn denote a random sample...Ch. 9.7 - Suppose that Y1, Y2, , Yn denote a random sample...Ch. 9.7 - Prob. 82ECh. 9.7 - Suppose that Y1, Y2, , Yn constitute a random...Ch. 9.7 - Prob. 84ECh. 9.7 - Let Y1, Y2,, Yn denote a random sample from the...Ch. 9.7 - Suppose that X1, X2, , Xm, representing yields per...Ch. 9.7 - A random sample of 100 voters selected from a...Ch. 9.7 - Prob. 88ECh. 9.7 - It is known that the probability p of tossing...Ch. 9.7 - A random sample of 100 men produced a total of 25...Ch. 9.7 - Find the MLE of based on a random sample of size...Ch. 9.7 - Prob. 92ECh. 9.7 - Prob. 93ECh. 9.7 - Suppose that is the MLE for a parameter . Let t()...Ch. 9.7 - A random sample of n items is selected from the...Ch. 9.7 - Consider a random sample of size n from a normal...Ch. 9.7 - The geometric probability mass function is given...Ch. 9.8 - Refer to Exercise 9.97. What is the approximate...Ch. 9.8 - Consider the distribution discussed in Example...Ch. 9.8 - Suppose that Y1, Y2, . . . , Yn constitute a...Ch. 9.8 - Let Y1, Y2, . . . , Yn denote a random sample of...Ch. 9.8 - Refer to Exercises 9.97 and 9.98. If a sample of...Ch. 9 - Prob. 103SECh. 9 - Prob. 104SECh. 9 - Refer to Exercise 9.38(b). Under the conditions...Ch. 9 - Prob. 106SECh. 9 - Suppose that a random sample of length-of-life...Ch. 9 - The MLE obtained in Exercise 9.107 is a function...Ch. 9 - Prob. 109SECh. 9 - Refer to Exercise 9.109. a Find the MLE N2 of N. b...Ch. 9 - Refer to Exercise 9.110. Suppose that enemy tanks...Ch. 9 - Let Y1, Y2, . . . , Yn denote a random sample from...
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