Statistics for Business & Economics
12th Edition
ISBN: 9781285528830
Author: David R. Anderson
Publisher: Cengage Learning US
expand_more
expand_more
format_list_bulleted
Concept explainers
Textbook Question
Chapter 8.3, Problem 29E
The travel-to-work time for residents of the 15 largest cities in the United States is reported in the 2003 Information Please Almanac. Suppose that a preliminary simple random sample of residents of San Francisco is used to develop a planning value of 6.25 minutes for the population standard deviation.
- a. If we want to estimate the population
mean travel-to-work time for San Francisco residents with a margin of error of 2 minutes, whatsample size should be used? Assume 95% confidence. - b. If we want to estimate the population mean travel-to-work time for San Francisco residents with a margin of error of 1 minute, what sample size should be used? Assume 95% confidence.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solutionStudents have asked these similar questions
A well-known company predominantly makes flat pack furniture for students. Variability with the automated machinery means the wood components are cut with a standard deviation in length of 0.45 mm. After they are cut the components are measured. If their length is more than 1.2 mm from the required length, the components are rejected.
a) Calculate the percentage of components that get rejected.
b) In a manufacturing run of 1000 units, how many are expected to be rejected?
c) The company wishes to install more accurate equipment in order to reduce the rejection rate by one-half, using the same ±1.2mm rejection criterion. Calculate the maximum acceptable standard deviation of the new process.
5. Let X and Y be independent random variables and let the superscripts denote
symmetrization (recall Sect. 3.6). Show that
(X + Y) X+ys.
8. Suppose that the moments of the random variable X are constant, that is, suppose
that EX" =c for all n ≥ 1, for some constant c. Find the distribution of X.
Chapter 8 Solutions
Statistics for Business & Economics
Ch. 8.1 - A simple random sample of 40 items resulted in a...Ch. 8.1 - A simple random sample of 50 items from a...Ch. 8.1 - A simple random sample of 60 items resulted in a...Ch. 8.1 - A 95% confidence interval for a population mean...Ch. 8.1 - Data were collected on the amount spent by 64...Ch. 8.1 - Nielsen Media Research conducted a study of...Ch. 8.1 - The Wall Street Journal reported that automobile...Ch. 8.1 - Studies show that massage therapy has a variety of...Ch. 8.1 - AARP reported on a study conducted to learn how...Ch. 8.1 - Playbill magazine reported that the mean annual...
Ch. 8.2 - For a t distribution with 16 degrees of freedom,...Ch. 8.2 - Find the t value(s) for each of the following...Ch. 8.2 - The following sample data are from a normal...Ch. 8.2 - A simple random sample with n = 54 provided a...Ch. 8.2 - Sales personnel for Skillings Distributors submit...Ch. 8.2 - A sample containing years to maturity and yield...Ch. 8.2 - The International Air Transport Association...Ch. 8.2 - Older people often have a hard time finding work....Ch. 8.2 - The average cost per night of a hotel room in New...Ch. 8.2 - Is your favorite TV program often interrupted by...Ch. 8.2 - Consumption of alcoholic beverages by young women...Ch. 8.2 - Disneys Hannah Montana: The Movie opened on Easter...Ch. 8.3 - How large a sample should be selected to provide a...Ch. 8.3 - The range for a set of data is estimated to be 36....Ch. 8.3 - Refer to the Scheer Industries example in Section...Ch. 8.3 - The U.S. Energy Information Administration (US...Ch. 8.3 - Annual starting salaries for college graduates...Ch. 8.3 - An online survey by ShareBuilder, a retirement...Ch. 8.3 - The travel-to-work time for residents of the 15...Ch. 8.3 - There has been a trend toward less driving in the...Ch. 8.4 - A simple random sample of 400 individuals provides...Ch. 8.4 - A simple random sample of 800 elements generates a...Ch. 8.4 - In a survey, the planning value for the population...Ch. 8.4 - At 95% confidence, how large a sample should be...Ch. 8.4 - The Consumer Reports National Research Center...Ch. 8.4 - According to statistics reported on CNBC, a...Ch. 8.4 - Towers Perrin, a New York human resources...Ch. 8.4 - According to Thomson Financial, through January...Ch. 8.4 - Prob. 39ECh. 8.4 - For many years businesses have struggled with the...Ch. 8.4 - Fewer young people are driving. In 1983, 87% of...Ch. 8.4 - A poll for the presidential campaign sampled 491...Ch. 8.4 - A Phoenix Wealth Management/Harris Interactive...Ch. 8 - A sample survey of 54 discount brokers showed that...Ch. 8 - A survey conducted by the American Automobile...Ch. 8 - The 92 million Americans of age 50 and over...Ch. 8 - Many stock market observers say that when the P/E...Ch. 8 - US Airways conducted a number of studies that...Ch. 8 - A recent article reported that there are...Ch. 8 - Mileage tests are conducted for a particular model...Ch. 8 - In developing patient appointment schedules, a...Ch. 8 - Annual salary plus bonus data for chief executive...Ch. 8 - The National Center for Education Statistics...Ch. 8 - A USA Today/CNN/Gallup survey of 369 working...Ch. 8 - Which would be hardest for you to give up: Your...Ch. 8 - Prob. 56SECh. 8 - The 2003 Statistical Abstract of the United States...Ch. 8 - A well-known bank credit card firm wishes to...Ch. 8 - Workers in several industries were surveyed to...Ch. 8 - Although airline schedules and cost are important...Ch. 8 - Young Professional Magazine Young Professional...Ch. 8 - Gulf Real Estate Properties Gulf Real Estate...Ch. 8 - Metropolitan Research, Inc. Metropolitan Research,...
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
- 9. The concentration function of a random variable X is defined as Qx(h) = sup P(x ≤ X ≤x+h), h>0. Show that, if X and Y are independent random variables, then Qx+y (h) min{Qx(h). Qr (h)).arrow_forward10. Prove that, if (t)=1+0(12) as asf->> O is a characteristic function, then p = 1.arrow_forward9. The concentration function of a random variable X is defined as Qx(h) sup P(x ≤x≤x+h), h>0. (b) Is it true that Qx(ah) =aQx (h)?arrow_forward
- 3. Let X1, X2,..., X, be independent, Exp(1)-distributed random variables, and set V₁₁ = max Xk and W₁ = X₁+x+x+ Isk≤narrow_forward7. Consider the function (t)=(1+|t|)e, ER. (a) Prove that is a characteristic function. (b) Prove that the corresponding distribution is absolutely continuous. (c) Prove, departing from itself, that the distribution has finite mean and variance. (d) Prove, without computation, that the mean equals 0. (e) Compute the density.arrow_forward1. Show, by using characteristic, or moment generating functions, that if fx(x) = ½ex, -∞0 < x < ∞, then XY₁ - Y2, where Y₁ and Y2 are independent, exponentially distributed random variables.arrow_forward
- 1. Show, by using characteristic, or moment generating functions, that if 1 fx(x): x) = ½exarrow_forward1990) 02-02 50% mesob berceus +7 What's the probability of getting more than 1 head on 10 flips of a fair coin?arrow_forward9. The concentration function of a random variable X is defined as Qx(h) sup P(x≤x≤x+h), h>0. = x (a) Show that Qx+b(h) = Qx(h).arrow_forward
- Suppose that you buy a lottery ticket, and you have to pick six numbers from 1 through 50 (repetitions allowed). Which combination is more likely to win: 13, 48, 17, 22, 6, 39 or 1, 2, 3, 4, 5, 6? barrow_forward2 Make a histogram from this data set of test scores: 72, 79, 81, 80, 63, 62, 89, 99, 50, 78, 87, 97, 55, 69, 97, 87, 88, 99, 76, 78, 65, 77, 88, 90, and 81. Would a pie chart be appropriate for this data? ganizing Quantitative Data: Charts and Graphs 45arrow_forward10 Meteorologists use computer models to predict when and where a hurricane will hit shore. Suppose they predict that hurricane Stat has a 20 percent chance of hitting the East Coast. a. On what info are the meteorologists basing this prediction? b. Why is this prediction harder to make than your chance of getting a head on your next coin toss? U anoiaarrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
- Glencoe Algebra 1, Student Edition, 9780079039897...AlgebraISBN:9780079039897Author:CarterPublisher:McGraw Hill
Glencoe Algebra 1, Student Edition, 9780079039897...
Algebra
ISBN:9780079039897
Author:Carter
Publisher:McGraw Hill
Use of ALGEBRA in REAL LIFE; Author: Fast and Easy Maths !;https://www.youtube.com/watch?v=9_PbWFpvkDc;License: Standard YouTube License, CC-BY
Compound Interest Formula Explained, Investment, Monthly & Continuously, Word Problems, Algebra; Author: The Organic Chemistry Tutor;https://www.youtube.com/watch?v=P182Abv3fOk;License: Standard YouTube License, CC-BY
Applications of Algebra (Digit, Age, Work, Clock, Mixture and Rate Problems); Author: EngineerProf PH;https://www.youtube.com/watch?v=Y8aJ_wYCS2g;License: Standard YouTube License, CC-BY