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Introductory Statistics (10th Edition)
10th Edition
ISBN: 9780321989178
Author: Neil A. Weiss
Publisher: PEARSON
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Textbook Question
Chapter 7, Problem 8RP
Income Tax and the IRS. In 2010, the Internal Revenue Service (IRS) sampled 308,946 tax returns to obtain estimates of various parameters. Data were published in Statistics of Income, Individual Income Tax Returns. According to that document, the mean income tax per return for the returns sampled was $11,266.
- a. Explain the meaning of sampling error in this context.
- b. If, in reality, the population mean income tax per return in 2010 was $11,354, how much sampling error was made in estimating that parameter by the sample mean of $11,266?
- c. If the IRS had sampled 400,000 returns instead of 308,946, would the sampling error necessarily have been smaller? Explain your answer.
- d. In future surveys, how can the IRS increase the likelihood of small sampling error?
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Chapter 7 Solutions
Introductory Statistics (10th Edition)
Ch. 7.1 - Why is sampling often preferable to conducting a...Ch. 7.1 - Why should you generally expect some error when...Ch. 7.1 - In Exercises 7.37.10, we have given population...Ch. 7.1 - In Exercises 7.37.10, we have given population...Ch. 7.1 - In Exercises 7.37.10, we have given population...Ch. 7.1 - Prob. 6ECh. 7.1 - In Exercises 7.37.10, we have given population...Ch. 7.1 - Prob. 8ECh. 7.1 - Prob. 9ECh. 7.1 - In Exercises 7.37.10, we have given population...
Ch. 7.1 - Exercises 7.117.23 are intended solely to provide...Ch. 7.1 - Exercises 7.117.23 are intended solely to provide...Ch. 7.1 - Exercises 7.117.23 are intended solely to provide...Ch. 7.1 - Exercises 7.117.23 are intended solely to provide...Ch. 7.1 - Exercises 7.117.23 are intended solely to provide...Ch. 7.1 - Exercises 7.117.23 are intended solely to provide...Ch. 7.1 - Exercises 7.117.23 are intended solely to provide...Ch. 7.1 - Exercises 7.117.23 are intended solely to provide...Ch. 7.1 - Exercises 7.117.23 are intended solely to provide...Ch. 7.1 - Exercises 7.117.23 are intended solely to provide...Ch. 7.1 - Prob. 21ECh. 7.1 - Exercises 7.117.23 are intended solely to provide...Ch. 7.1 - Prob. 23ECh. 7.1 - Prob. 24ECh. 7.1 - Suppose that a random sample of size 1 is to be...Ch. 7.2 - Although, in general, you cannot know the sampling...Ch. 7.2 - Why is obtaining the mean and standard deviation...Ch. 7.2 - Does the sample size have an effect on the mean of...Ch. 7.2 - Does the sample size have an effect on the...Ch. 7.2 - Explain why increasing the sample size tends to...Ch. 7.2 - Prob. 31ECh. 7.2 - Prob. 32ECh. 7.2 - Prob. 33ECh. 7.2 - Prob. 34ECh. 7.2 - Exercises 7.337.40 require that you have done...Ch. 7.2 - Prob. 36ECh. 7.2 - Prob. 37ECh. 7.2 - Prob. 38ECh. 7.2 - Prob. 39ECh. 7.2 - Prob. 40ECh. 7.2 - Exercises 7.417.45 require that you have done...Ch. 7.2 - Prob. 42ECh. 7.2 - Prob. 43ECh. 7.2 - Exercises 7.417.45 require that you have done...Ch. 7.2 - Exercises 7.417.45 require that you have done...Ch. 7.2 - Young Adults at Risk. Research by R. Pyhala et al....Ch. 7.2 - Baby Weight. The paper Are Babies Normal? by T....Ch. 7.2 - Menopause in Mexico. In the article Age at...Ch. 7.2 - Mobile Homes. According to the U.S. Census Bureau...Ch. 7.2 - Undergraduate Binge Drinking. Alcohol consumption...Ch. 7.2 - Earthquakes. According to The Earth: Structure,...Ch. 7.2 - Bachelors Completion. As reported by the U.S....Ch. 7.2 - SAT Scores. Each year, thousands of high school...Ch. 7.2 - Unbiased and Biased Estimators. A statistic is...Ch. 7.2 - For Exercises 7.557.57, refer to Equations (7.1)...Ch. 7.2 - For Exercises 7.557.57, refer to Equations (7.1)...Ch. 7.2 - Prob. 57ECh. 7.2 - Prob. 58ECh. 7.2 - Gestation Periods of Humans. For humans, gestation...Ch. 7.2 - Prob. 60ECh. 7.3 - A variable of a population has a mean of = 100...Ch. 7.3 - A variable of a population has a mean of = 35 and...Ch. 7.3 - A variable of a population is normally distributed...Ch. 7.3 - A variable of a population has mean and standard...Ch. 7.3 - Refer to Fig. 7.6 on page 323. a. Why are the four...Ch. 7.3 - According to the central limit theorem, for a...Ch. 7.3 - Brain Weights. In 1905, R. Pearl published the...Ch. 7.3 - New York City 10-km Run. As reported by Runners...Ch. 7.3 - Teacher Salaries. Data on salaries in the public...Ch. 7.3 - Loan Amounts. B. Ciochetti et al. studied mortgage...Ch. 7.3 - Nurses and Hospital Stays. In the article A...Ch. 7.3 - Women at Work. In the article Job Mobility and...Ch. 7.3 - Ethanol Railroad Tariffs. An ethanol railroad...Ch. 7.3 - Taller Young Women. In the document Anthropometric...Ch. 7.3 - Poverty and Dietary Calcium. Calcium is the most...Ch. 7.3 - Early-Onset Dementia. Dementia is the loss of the...Ch. 7.3 - Worker Fatigue. A study by M. Chen et al. titled...Ch. 7.3 - Prob. 78ECh. 7.3 - Use the empirical rule for variables to answer the...Ch. 7.3 - Testing for Content Accuracy. A brand of...Ch. 7.3 - Gestation Periods of Humans. For humans, gestation...Ch. 7.3 - Emergency Room Traffic. A variable is said to have...Ch. 7 - Define sampling error.Ch. 7 - Prob. 2RPCh. 7 - Prob. 3RPCh. 7 - Prob. 4RPCh. 7 - Officer Salaries. The following table gives the...Ch. 7 - Officer Salaries. Refer to Problem 5. a. Use the...Ch. 7 - The following graph shows the curve for a normally...Ch. 7 - Income Tax and the IRS. In 2010, the Internal...Ch. 7 - New Car Passion. Edmunds.com publishes information...Ch. 7 - Prob. 10RPCh. 7 - Prob. 11RPCh. 7 - Prob. 12RPCh. 7 - Western Pygmy-Possum. Refer to Problem 12. a. Find...Ch. 7 - Prob. 14RPCh. 7 - Life Insurance in Force. The American Council of...Ch. 7 - Prob. 16RPCh. 7 - Prob. 17RPCh. 7 - Athletic Coping Skills Inventory. The Athletic...Ch. 7 - Random Numbers. A variable is said to be uniformly...Ch. 7 - Prob. 1FDACh. 7 - At the beginning of this chapter, we discussed a...
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