Mathematical Statistics with Applications
7th Edition
ISBN: 9781133384380
Author: Dennis Wackerly; William Mendenhall; Richard L. Scheaffer
Publisher: Cengage Learning US
expand_more
expand_more
format_list_bulleted
Concept explainers
Videos
Textbook Question
Chapter 8.4, Problem 34E
We can place a 2-standard-deviation bound on the error of estimation with any estimator for which we can find a reasonable estimate of the standard error. Suppose that Y1, Y2, … , Yn represent a random sample from a Poisson distribution with mean λ. We know that V(Yi) = λ, and hence
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
Suppose you fit a simple Poisson model such that in A = XB where B = 1.9. What would the variance be if x = -0.8 ?
Suppose X and Y are independent. X has a mean of 1 and variance of 1, Y has a mean of 0, and variance of 2.
Let S=X+Y, calculate E(S) and Var(S).
Let Z=2Y^2+1/2 X+1 calculate E(Z). Hint: for any random variable X, we have Var(X)=E(X-E(X))^2=E(X^2 )-(E(X))^2, you may want to find EY^2 with this.
Calculate cov(S,X). Hint: similarly, we have cov(Z,X)=E(ZX)-E(Z)E(X),
Calculate cov(Z,X).
Are Z and X independent? Are Z and Y independent? Why?
What about mean independence?
A random sample of n, 20 winter days in Denver gave a sample mean pollution index x, = 43. Previous studles show that o,- 10. For Englewood (a suburb of Denver), a random sample of n, - 19 winter days gave a sample mean pollution Index of x, = 37. Previous studies show that g,
-13. Assume the pollution Index is normally distributed in both Englewood and Denver. Do these data indicate that the mean population pollution index of Englewood is different (either way) from that of Denver in the winter? Use a 1% level of significance.
(a) what is the level of significance?
State the null and alternate hypotheses.
(b) what sampling distribution will you use? What assumptions are you making?
O The Student's t. We assume that both population distributions are approximately normal with unknown standard deviations.
O The Student's t. We assume that both population distributions are approximately normal with known standard devtations.
O The standard normal. We assume that both population…
Chapter 8 Solutions
Mathematical Statistics with Applications
Ch. 8.2 - Using the identity ()=[E()]+[E()]=[E()]+B(), Show...Ch. 8.2 - a. If is an unbiased estimator for , what is B()?...Ch. 8.2 - Suppose that is an estimator for a parameter and...Ch. 8.2 - Refer to Exercise 8.1. a. If is an unbiased...Ch. 8.2 - Refer to Exercises 8.1 and consider the unbiased...Ch. 8.2 - Suppose that E(1)=E(2)=, V(1)=12, and V(2)=22....Ch. 8.2 - Consider the situation described in Exercise 8.6....Ch. 8.2 - Suppose that Y1, Y2, Y3 denote a random sample...Ch. 8.2 - Suppose that Y1, Y2,, Yn constitute a random...Ch. 8.2 - The number of breakdowns per week for a type of...
Ch. 8.2 - Let Y1, Y2, , Yn denote a random sample of size n...Ch. 8.2 - The reading on a voltage meter connected to a test...Ch. 8.2 - We have seen that if Y has a binomial distribution...Ch. 8.2 - Prob. 14ECh. 8.2 - Let Y, Y2,,Yn denote a random sample of size n...Ch. 8.2 - Suppose that Y1, Y2,,Yn constitute a random sample...Ch. 8.2 - If Y has a binomial distribution with parameters n...Ch. 8.2 - Let Y1, Y2, , Yn denote a random sample of size n...Ch. 8.2 - Prob. 19ECh. 8.2 - Suppose that Y1, Y2, Y3, Y4 denote a random sample...Ch. 8.4 - An investigator is interested in the possibility...Ch. 8.4 - An increase in the rate of consumer savings...Ch. 8.4 - The Environmental Protection Agency and the...Ch. 8.4 - A study was conducted to compare the mean number...Ch. 8.4 - The Mars twin rovers, Spirit and Opportunity,...Ch. 8.4 - A random sample of 985 likely votersthose who are...Ch. 8.4 - In a study of the relationship between birth order...Ch. 8.4 - Sometimes surveys provide interesting information...Ch. 8.4 - Refer to Exercise 8.29. Give the point estimate...Ch. 8.4 - In a study to compare the perceived effects of two...Ch. 8.4 - An auditor randomly samples 20 accounts receivable...Ch. 8.4 - Refer to Exercise 8.32. From the data given on the...Ch. 8.4 - We can place a 2-standard-deviation bound on the...Ch. 8.4 - Prob. 35ECh. 8.4 - Prob. 36ECh. 8.4 - Refer to Exercise 8.36. An engineer observes n =...Ch. 8.4 - Prob. 38ECh. 8.5 - Suppose that the random variable Y has a gamma...Ch. 8.5 - Suppose that the random variable Y is an...Ch. 8.5 - Suppose that Y is normally distributed with mean 0...Ch. 8.5 - Prob. 42ECh. 8.5 - Prob. 43ECh. 8.5 - Let Y have probability density function...Ch. 8.5 - Refer to Exercise 8.44. a Use the pivotal quantity...Ch. 8.5 - Refer to Example 8.4 and suppose that Y is a...Ch. 8.5 - Refer to Exercise 8.46. Assume that Y1, Y2, , Yn...Ch. 8.5 - Prob. 48ECh. 8.6 - Refer to Example 8.8. In this example, p1 and p2...Ch. 8.6 - Prob. 51ECh. 8.6 - Prob. 52ECh. 8.6 - Prob. 53ECh. 8.6 - Prob. 54ECh. 8.6 - Prob. 55ECh. 8.6 - Is Americas romance with movies on the wane? In a...Ch. 8.6 - Refer to Exercise 8.29. According to the result...Ch. 8.6 - The administrators for a hospital wished to...Ch. 8.6 - When it comes to advertising, tweens are not ready...Ch. 8.6 - What is the normal body temperature for healthy...Ch. 8.6 - A small amount of the trace element selenium, from...Ch. 8.6 - The following statistics are the result of an...Ch. 8.6 - Most Americans love participating in or at least...Ch. 8.6 - In a CNN/USA Today/Gallup Poll, 1000 Americans...Ch. 8.6 - For a comparison of the rates of defectives...Ch. 8.6 - Historically, biology has been taught through...Ch. 8.6 - One suggested method for solving the...Ch. 8.6 - Prob. 68ECh. 8.6 - Prob. 69ECh. 8.7 - Let Y be a binomial random variable with parameter...Ch. 8.7 - A state wildlife service wants to estimate the...Ch. 8.7 - Telephone pollsters often interview between 1000...Ch. 8.7 - Refer to Exercise 8.59. How many tweens should...Ch. 8.7 - Prob. 74ECh. 8.7 - Prob. 75ECh. 8.7 - Refer to the comparison of the daily adult intake...Ch. 8.7 - Prob. 77ECh. 8.7 - Refer to Exercise 8.65. How many items should be...Ch. 8.7 - Refer to Exercise 8.66. a Another similar study is...Ch. 8.8 - Although there are many treatments for bulimia...Ch. 8.8 - The carapace lengths of ten lobsters examined in a...Ch. 8.8 - Scholastic Assessment Test (SAT) scores, which...Ch. 8.8 - Chronic anterior compartment syndrome is a...Ch. 8.8 - Organic chemists often purify organic compounds by...Ch. 8.8 - Two new drugs were given to patients with...Ch. 8.8 - The Environmental Protection Agency (EPA) has...Ch. 8.8 - Refer to Exercise 8.88. Another common...Ch. 8.8 - Do SAT scores for high school students differ...Ch. 8.8 - Seasonal ranges (in hectares) for alligators were...Ch. 8.8 - Solid copper produced by sintering (heating...Ch. 8.8 - Prob. 93ECh. 8.8 - Suppose that we obtain independent samples of...Ch. 8.9 - The EPA has set a maximum noise level for heavy...Ch. 8.9 - In Exercise 8.81, we gave the carapace lengths of...Ch. 8.9 - Suppose that S2 is the sample variance based on a...Ch. 8.9 - Prob. 98ECh. 8.9 - Prob. 99ECh. 8.9 - Industrial light bulbs should have a mean life...Ch. 8.9 - In laboratory work, it is desirable to run careful...Ch. 8.9 - The ages of a random sample of live university...Ch. 8.9 - A precision instrument is guaranteed to read...Ch. 8 - Prob. 104SECh. 8 - Prob. 105SECh. 8 - In a controlled pollination study involving Phlox...Ch. 8 - Prob. 107SECh. 8 - Prob. 108SECh. 8 - To estimate the proportion of unemployed workers...Ch. 8 - Prob. 110SECh. 8 - Prob. 111SECh. 8 - Prob. 112SECh. 8 - Prob. 113SECh. 8 - Prob. 114SECh. 8 - Prob. 115SECh. 8 - Do we lose our memory capacity as we get older? In...Ch. 8 - Prob. 117SECh. 8 - Prob. 118SECh. 8 - Prob. 119SECh. 8 - Two methods for teaching reading were applied to...Ch. 8 - Prob. 121SECh. 8 - Prob. 122SECh. 8 - Prob. 123SECh. 8 - Prob. 124SECh. 8 - Prob. 125SECh. 8 - Prob. 126SECh. 8 - Prob. 127SECh. 8 - Prob. 128SECh. 8 - Prob. 129SECh. 8 - Prob. 130SECh. 8 - Refer to Exercises 1.129 and 1.130. S2 and S2 are...Ch. 8 - Prob. 132SECh. 8 - Prob. 133SECh. 8 - Prob. 134SECh. 8 - Prob. 135SECh. 8 - Prob. 136SE
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, statistics and related others by exploring similar questions and additional content below.Similar questions
- What does the y -intercept on the graph of a logistic equation correspond to for a population modeled by that equation?arrow_forwardOlympic Pole Vault The graph in Figure 7 indicates that in recent years the winning Olympic men’s pole vault height has fallen below the value predicted by the regression line in Example 2. This might have occurred because when the pole vault was a new event there was much room for improvement in vaulters’ performances, whereas now even the best training can produce only incremental advances. Let’s see whether concentrating on more recent results gives a better predictor of future records. (a) Use the data in Table 2 (page 176) to complete the table of winning pole vault heights shown in the margin. (Note that we are using x=0 to correspond to the year 1972, where this restricted data set begins.) (b) Find the regression line for the data in part ‚(a). (c) Plot the data and the regression line on the same axes. Does the regression line seem to provide a good model for the data? (d) What does the regression line predict as the winning pole vault height for the 2012 Olympics? Compare this predicted value to the actual 2012 winning height of 5.97 m, as described on page 177. Has this new regression line provided a better prediction than the line in Example 2?arrow_forwardDerive that the variance of the forecasted error using Exponential Smoothing (ES) method is given by 20² Var(et) 2 – α Where o² is the variance of individual observation and a is the parameter in the ES method. =arrow_forward
- Suppose Y₁, Y2,, Yn is an iid sample from a gamma population distribution with shape parameter a = 2 and scale parameter 0, where > 0 is unknown. a. Find a function of the sample mean Y which is an unbiased estimator of 0. Also, find the variance of your unbiased estimator. b. Find two unbiased estimators of 7(0) = 0².arrow_forward9arrow_forwardLet X₁, X2, X3, Xn be a random sample with unknown mean EX; = µ, and unknown variance Var(X₂) = o². Suppose that we would like to estimate 0 = μ². We define the estimator as 2 • - (™)² - [ 2x]* Xk to estimate 0. Is an unbiased estimator of ? Why?arrow_forward
- Consider (Y, X) values in a population as (8, 2), (9, 3), (10, 3), (12, 5), (14, 6), (16, 6) and (17, 8). Draw all possible samples from this population and compute Ratio estimator for each sample. Show that the ratio estimator is a biased estimator of population mean but has smaller mean square error as compared with the variance of mean per unit estimator.arrow_forwardSuppose that f(x) = 0.125x for 0 < x < 4 Determine the mean and the variance of X.arrow_forwardsuppose you and a friend each take different random samples of data pairs (x,y) from the same popuation. Assumethe samples are the same size. Based on your samples, you compute r=0.83. Based on her sample, your friend computes r=0.79. Is your friends value for r wrong?arrow_forward
- If X₁, X₂,..., Xn are the values of a random sample from an exponential population, find the maximum likelihood estimator of its parameter 0.arrow_forwardThe number of clients a store has during a week is Poisson distributed with - 25. The amount of money spent by each client follows a random = el,000t+250t2. Assuming the mean A variable with moment generating function o(t) independence between the number of clients, and the amount of money spent by each client. Find the mean and variance of the amount of money received by the store every week.arrow_forwardThe pdf of random variable X is given as ƒx(x) = Find the i) Mean ii) Mean of the square [0.3507√x 0arrow_forwardarrow_back_iosSEE MORE QUESTIONSarrow_forward_ios
Recommended textbooks for you
Linear Algebra: A Modern IntroductionAlgebraISBN:9781285463247Author:David PoolePublisher:Cengage Learning
College AlgebraAlgebraISBN:9781305115545Author:James Stewart, Lothar Redlin, Saleem WatsonPublisher:Cengage Learning
Big Ideas Math A Bridge To Success Algebra 1: Stu...AlgebraISBN:9781680331141Author:HOUGHTON MIFFLIN HARCOURTPublisher:Houghton Mifflin Harcourt
Linear Algebra: A Modern Introduction
Algebra
ISBN:9781285463247
Author:David Poole
Publisher:Cengage Learning
College Algebra
Algebra
ISBN:9781305115545
Author:James Stewart, Lothar Redlin, Saleem Watson
Publisher:Cengage Learning
Big Ideas Math A Bridge To Success Algebra 1: Stu...
Algebra
ISBN:9781680331141
Author:HOUGHTON MIFFLIN HARCOURT
Publisher:Houghton Mifflin Harcourt
Statistics 4.1 Point Estimators; Author: Dr. Jack L. Jackson II;https://www.youtube.com/watch?v=2MrI0J8XCEE;License: Standard YouTube License, CC-BY
Statistics 101: Point Estimators; Author: Brandon Foltz;https://www.youtube.com/watch?v=4v41z3HwLaM;License: Standard YouTube License, CC-BY
Central limit theorem; Author: 365 Data Science;https://www.youtube.com/watch?v=b5xQmk9veZ4;License: Standard YouTube License, CC-BY
Point Estimate Definition & Example; Author: Prof. Essa;https://www.youtube.com/watch?v=OTVwtvQmSn0;License: Standard Youtube License
Point Estimation; Author: Vamsidhar Ambatipudi;https://www.youtube.com/watch?v=flqhlM2bZWc;License: Standard Youtube License