Introductory Statistics (10th Edition)
10th Edition
ISBN: 9780321989178
Author: Neil A. Weiss
Publisher: PEARSON
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Chapter 7.2, Problem 51E
Earthquakes. According to The Earth: Structure, Composition and Evolution (The Open University, S237), for earthquakes with a magnitude of 7.5 or greater on the Richter scale, the time between successive earthquakes has a
- a. On average, what would you expect to be the mean of the four times?
- b. How much variation would you expect from your answer in part (a)? (Hint: Use the three-standard-deviations rule.)
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Based on the chi-square test, which sample variables adequately represent the university’s student population and which ones do not? Support your answer by providing the p-value of the chi-square test and explaining what it means.
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A marketing professor has surveyed the students at her university to better understand attitudes towards PPT usage for higher education. To be able to make inferences to the entire student body, the sample drawn needs to represent the university’s student population on all key characteristics. The table below shows the five key student demographic variables. The professor found the breakdown of the overall student body in the university’s fact book posted online.
A non-parametric chi-square test was used to test the sample demographics against the population percentages shown in the table above. Review the output for the five chi-square tests on the following pages and answer the five questions:
Based on the chi-square test, which sample variables adequately represent the university’s student population and which ones do not? Support your answer by providing the p-value of the chi-square test and explaining what it means.
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A retail chain is interested in determining whether a digital video point-of-purchase (POP) display would stimulate higher sales for a brand advertised compared to the standard cardboard point-of-purchase display. To test this, a one-shot static group design experiment was conducted over a four-week period in 100 different stores. Fifty stores were randomly assigned to the control treatment (standard display) and the other 50 stores were randomly assigned to the experimental treatment (digital display). Compare the sales of the control group (standard POP) to the experimental group (digital POP).
What were the average sales for the standard POP display (control group)?
What were the sales for the digital display (experimental group)?
What is the (mean) difference in sales between the experimental group and control group?
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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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