Introduction To Statistics And Data Analysis
6th Edition
ISBN: 9781337793612
Author: PECK, Roxy.
Publisher: Cengage Learning,
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Chapter 9.3, Problem 41E
The paper “The Effects of Adolescent Volunteer Activities on the Perception of Local Society and Community Spirit Mediated by Self-Conception” (Advanced Science and Technology letters [2016]: 19–23) describes a survey of a large representative sample of middle school children in South Korea.
One question in the survey asked how much time per year the children spent in volunteer activities. The sample mean was 14.76 hours and the sample standard deviation was 16.54 hours.
- a. Based on the reported sample mean and sample standard deviation, explain why it is not reasonable to think that the distribution of volunteer times for the population of South Korean middle school students is approximately normal.
- b. The
sample size was not given in the paper, but the sample size was described as large. Suppose that the sample size was 500. Explain why it is reasonable to use a one-sample t confidenceinterval to estimate the population mean even though the population distribution is not approximately normal. - c. Calculate and interpret a confidence interval for the mean number of hours spent in volunteer activities per year for South Korean middle school children.
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Chapter 9 Solutions
Introduction To Statistics And Data Analysis
Ch. 9.1 - Three different statistics are being considered...Ch. 9.1 - a. Why is an unbiased statistic generally...Ch. 9.1 - The report The 2016 Consumer Financial Literacy...Ch. 9.1 - The authors of the paper Influence of Biofeedback...Ch. 9.1 - Each person in a random sample of 20 students at a...Ch. 9.1 - Suppose that each of 935 smokers received a...Ch. 9.1 - Given below are the sodium contents (in mg) for...Ch. 9.1 - A random sample of n = 12 four-year-old red pine...Ch. 9.1 - A random sample of 10 houses heated with natural...Ch. 9.2 - Explain which would result in a wider large-sample...
Ch. 9.2 - Explain which would result in a wider large-sample...Ch. 9.2 - The formula used to calculate a large-sample...Ch. 9.2 - The use of the interval p(zcriticalvalue)p(1p)n...Ch. 9.2 - For each of the following combinations of sample...Ch. 9.2 - Discuss how each of the following factors affects...Ch. 9.2 - The USA TODAY Snapshot titled Social Media...Ch. 9.2 - Based on data from a survey of 1200 randomly...Ch. 9.2 - The report Parents, Teens and Digital Monitoring...Ch. 9.2 - If a hurricane was headed your way, would you...Ch. 9.2 - The USA TODAY Snapshot titled Big Bang Theory (USA...Ch. 9.2 - The article Most Dog Owners Take More Pictures of...Ch. 9.2 - The Princeton Review 2016 College Hopes and...Ch. 9.2 - The USA TODAY Snapshot titled Babys First Photo...Ch. 9.2 - The report Job Seeker Nation Study...Ch. 9.2 - USA TODAY reported that the proportion of...Ch. 9.2 - The USA TODAY Snapshot titled Have a Nice Trip...Ch. 9.2 - Business Insider reported that a study...Ch. 9.2 - In 2010, the National Football League adopted new...Ch. 9.2 - The article Most Americans Dont Understand the...Ch. 9.2 - The Gallup Organization conducts an annual survey...Ch. 9.2 - The article Hospitals Dispute Medtronic Data on...Ch. 9.2 - Based on survey of a representative sample of 1000...Ch. 9.2 - A discussion of digital ethics appears in the...Ch. 9.2 - In spite of the potential safety hazards, some...Ch. 9.2 - In 2010, the online security firm Symantec...Ch. 9.3 - Given a variable that has at distribution with the...Ch. 9.3 - The formula used to calculate a confidence...Ch. 9.3 - USA TODAY reported that the average amount of...Ch. 9.3 - Samples of two different models of cars were...Ch. 9.3 - USA TODAY reported that the average amount of...Ch. 9.3 - The paper The Effects of Adolescent Volunteer...Ch. 9.3 - Medical research has shown that repeated wrist...Ch. 9.3 - Students in a representative sample of 65...Ch. 9.3 - The paper referenced in the previous exercise also...Ch. 9.3 - Suppose that a random sample of 50 bottles of a...Ch. 9.3 - The authors of the paper Driving Performance While...Ch. 9.3 - The article The Association Between Television...Ch. 9.3 - The paper Patterns and Composition of Weight...Ch. 9.3 - Because of safety considerations, in May 2003 the...Ch. 9.3 - Example 9.3 gave the following airborne times (in...Ch. 9.3 - Consumer Reports gave the following mileage...Ch. 9.3 - Five students visiting the student health center...Ch. 9.3 - The Bureau of Alcohol, Tobacco, and Firearms...Ch. 9.3 - The formula described in this section for...Ch. 9.4 - The following quote is from the article Credit...Ch. 9.4 - Authors of the news release titled Major Gaps...Ch. 9.4 - The paper The Curious Promiscuity of Queen Honey...Ch. 9.5 - A survey on SodaHead...Ch. 9.5 - Prob. 59ECh. 9.5 - Prob. 60ECh. 9.5 - Prob. 61ECh. 9.5 - Prob. 62ECh. 9.5 - Prob. 63ECh. 9.5 - Prob. 64ECh. 9.5 - Prob. 65ECh. 9.6 - Prob. 66ECh. 9.6 - Prob. 67ECh. 9.6 - Teams in the National Football League (NFL) are...Ch. 9.6 - Prob. 69ECh. 9.6 - The Economist collects data each year on the price...Ch. 9.6 - Major League Baseball (MLB) includes two groups of...Ch. 9 - The article Write It by Hand to Make It Stick...Ch. 9 - Prob. 73CRCh. 9 - The report The 2016 Consumer Financial Literacy...Ch. 9 - The report The Politics of Climate (Pew Research...Ch. 9 - The report referenced in the previous exercise...Ch. 9 - Data from a survey of a representative sample was...Ch. 9 - A manufacturer of small appliances purchases...Ch. 9 - A manufacturer of college textbooks is interested...Ch. 9 - The confidence intervals presented in this chapter...Ch. 9 - Prob. 81CRCh. 9 - The interval from 2.33 to 1.75 captures an area of...
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