2.99 See Answer

Question: Refer to Exercise 11.52. a. Find


Refer to Exercise 11.52.
a. Find the margin of error for the estimate of p.
b. Obtain a sample size that will ensure a margin of error of at most 0.02 for a 95% confidence interval without making a guess for the observed value of pˆ.
c. Find a 95% confidence interval for p if, for a sample of the size determined in part (b), 36.0% of those sampled drink alcoholic beverages at least once a week.
d. Determine the margin of error for the estimate in part (c) and compare it to the margin of error specified in part (b).
e. Repeat parts (b)–(d) if you can reasonably presume that the percentage of adults sampled who drink alcoholic beverages at least once a week will be at most 40%.
f. Compare the results you obtained in parts (b)–(d) with those obtained in part (e).

Data from Exercise 11.52:
In a nationwide survey, conducted by Pulse Opinion Research, LLC for Rasmussen Reports, 1000 American adults were asked, among other things, whether they drink alcoholic beverages at least once a week; 38% said “yes.” Determine and interpret a 95% confidence interval for the proportion, p, of all American adults who drink alcoholic beverages at least once a week.


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> The Quinnipiac University Poll conducts nationwide surveys as a public service and for research. This problem is based on the results of one such poll. Independent simple random samples of 300 residents each in red (predominantly Republican), blue (predo

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> The U.S. Census Bureau compiles data on the U.S. population by region and race and publishes its findings in Current Population Reports. Independent simple random samples of residents in the four U.S. regions gave the following data on race. At the 1% si

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> In the article “The Influence of Theme as Slot Machine Attribute on Casino Gamers Decision-Making” (American Journal of Applied Sciences, Vol. 10, No. 7, pp. 734–739), E. Wannenburg et al. explore the effects of theme on slot-machine gamers. Independent

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> Self-concept can be defined as the general view of oneself in terms of personal value and capabilities. A study of whether visual impairment affects self-concept was reported in the article “An Exploration into Self Concept: A Comparative Analysis betwee

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> We have given the number of successes and the sample size for a simple random sample from a population. In each case, do the following. a. Determine the sample proportion. b. Decide whether using the one-proportion z-test is appropriate. c. If appropriat

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> In the February 2013 article “Offshore Drilling Support High as Deepwater Horizon Oil Spill Trial Opens,” E. Swanson reported on a HuffPost and YouGov poll that asked Americans what they think about increased offshore drilling for oil and natural gas. Of

> In a New York Times article “More Mothers Breast-Feed, in First Months at Least,” G. Harris reported that 77% of new mothers breast-feed their infants at least briefly, the highest rate seen in the United States in more than a decade. His report was base

> A Pew Internet & American Life Project examined Internet social networking. Among a sample of 929 online adults 18–29 years old, 836 said they use social networking sites. Determine a 95% confidence interval for the percentage of all online adults 18–29

> A poll by Gallup asked, “If you won 10 million dollars in the lottery, would you continue to work or stop working?” Of the 1039 American adults surveyed, 707 said that they would continue working. Obtain a 95% confidence interval for the proportion of al

> We have given the number of successes and the sample size for a simple random sample from a population. In each case, a. use the one-proportion plus-four z-interval procedure to find the required confidence interval. b. compare your result with the corre

> We have given the number of successes and the sample size for a simple random sample from a population. In each case, a. use the one-proportion plus-four z-interval procedure to find the required confidence interval. b. compare your result with the corre

> Give one reason why constructing and reading graphs and charts carefully is important.

> According to a study published in the Journal of the American Public Health Association, lefthanded people do not die at an earlier age than right-handed people, contrary to the conclusion of a highly publicized report done 2 years earlier. The investiga

> We have given the number of successes and the sample size for a simple random sample from a population. In each case, a. use the one-proportion plus-four z-interval procedure to find the required confidence interval. b. compare your result with the corre

> We have given the number of successes and the sample size for a simple random sample from a population. In each case, a. use the one-proportion plus-four z-interval procedure to find the required confidence interval. b. compare your result with the corre

> We have given the number of successes and the sample size for a simple random sample from a population. In each case, a. use the one-proportion plus-four z-interval procedure to find the required confidence interval. b. compare your result with the corre

> For what is the phrase “number of failures” an abbreviation?

> We have given the number of successes and the sample size for a simple random sample from a population. In each case, a. use the one-proportion plus-four z-interval procedure to find the required confidence interval. b. compare your result with the corre

> In discussing the sample size required for obtaining a confidence interval with a prescribed confidence level and margin of error, we made the following statement: “. . . we should be aware that, if the observed value of pˆ is closer to 0.5 than is our e

> In discussing the sample size required for obtaining a confidence interval with a prescribed confidence level and margin of error, we made the following statement: “If we have in mind a likely range for the observed value of pˆ, then, in light of Fig. 11

> What important theorem in statistics implies that, for a large sample size, the possible sample proportions of that size have approximately a normal distribution?

> A poll conducted by Gallup in December 2013 asked a sample of American adults whether they approved of the way President Obama was doing his job; 42% said yes, with a margin of error of plus or minus 3 percentage points. During that same time period, Qui

> On Thursday, June 13, 1996, then Arizona Governor Fife Symington was indicted on 23 counts of fraud and extortion. Just hours after the federal prosecutors announced the indictment, several polls were conducted of Arizonans asking whether they thought Sy

> One of the most important distributions in statistics is the standard normal distribution. a. Use the technology of your choice to generate a sample of 3000 observations from a variable that has the standard normal distribution. b. Use the technology of

> A company manufactures goods that are sold exclusively by mail order. The director of market research needed to test market a new product. She planned to send brochures to a random sample of households and use the proportion of orders obtained as an esti

> Refer to Exercise 11.54. a. Find the margin of error for the estimate of the percentage. b. Obtain a sample size that will ensure a margin of error of at most 5 percentage points for a 90% confidence interval without making a guess for the observed value

> Refer to Exercise 11.53. a. Find the margin of error for the estimate of the percentage. b. Obtain a sample size that will ensure a margin of error of at most 1.5 percentage points for a 99% confidence interval without making a guess for the observed val

> Regarding the phrase “number of successes”: a. For what is it an abbreviation? b. What symbol is used for it?

> Refer to Exercise 11.51. a. Determine the margin of error for the estimate of p. b. Obtain a sample size that will ensure a margin of error of at most 0.01 for a 95% confidence interval without making a guess for the observed value of pˆ. c. Find a 95% c

> According to the Internal Revenue Service, among people entitled to tax refunds, those who file online receive their refunds twice as fast as paper filers. A study conducted by International Communications Research (ICR) of Media, Pennsylvania, found tha

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> The infant mortality rate (IMR) is the number of infant deaths per 1000 live births. Suppose that you have been commissioned to estimate the IMR in Singapore. From a random sample of 1109 live births in Singapore, you find that 0.361% of them resulted in

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> In this exercise, use technology to work Exercise 2.159, as follows: a. Use the technology of your choice to obtain 50 random integers between 0 and 9. b. Use the technology of your choice to get a relative-frequency histogram based on single-value group

> During one year, Malaysia was the site of an encephalitis outbreak caused by the Nipah virus, a paramyxovirus that appears to spread from pigs to workers on pig farms. As reported by K. Goh et al. in the paper “Clinical Features of Nipah Virus Encephalit

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> In the article “Explaining an Unusual Allergy,” appearing on the Everyday Health Network, Dr. A. Feldweg explained that allergy to sulfites is usually seen in patients with asthma. The typical reaction is a sudden increase in asthma symptoms after eating

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> Regarding a sample proportion: a. What is it? b. What symbol is used for it?

> In a HuffPost Style and YouGov poll, 1000 U.S. adults were asked about their online vs. in-store clothes shopping. One finding was that 32% of respondents never clothes-shop online. Find and interpret a 95% confidence interval for the proportion of all U

> We have specified a margin of error, a confidence level, and a likely range for the observed value of the sample proportion. Obtain a sample size that will ensure a margin of error of at most the one specified (provided of course that the observed value

> We have specified a margin of error, a confidence level, and a likely range for the observed value of the sample proportion. Obtain a sample size that will ensure a margin of error of at most the one specified (provided of course that the observed value

> We have specified a margin of error, a confidence level, and a likely range for the observed value of the sample proportion. Obtain a sample size that will ensure a margin of error of at most the one specified (provided of course that the observed value

> This exercise can be done individually or, better yet, as a class project. a. Use a table of random numbers or a random-number generator to obtain 50 random integers between 0 and 9. b. Without graphing the distribution of the 50 numbers you obtained, gu

> We have specified a margin of error, a confidence level, and a likely range for the observed value of the sample proportion. Obtain a sample size that will ensure a margin of error of at most the one specified (provided of course that the observed value

> We have specified a margin of error, a confidence level, and a likely range for the observed value of the sample proportion. Obtain a sample size that will ensure a margin of error of at most the one specified (provided of course that the observed value

> We have specified a margin of error, a confidence level, and a likely range for the observed value of the sample proportion. Obtain a sample size that will ensure a margin of error of at most the one specified (provided of course that the observed value

> We have specified the margin of errors and confidence levels. Additionally, we have, in each case, provided an educated guess for the observed value of the sample proportion. For each exercise, a. obtain a sample size that will ensure a margin of error o

> We have specified the margin of errors and confidence levels. Additionally, we have, in each case, provided an educated guess for the observed value of the sample proportion. For each exercise, a. obtain a sample size that will ensure a margin of error o

> We have specified the margin of errors and confidence levels. Additionally, we have, in each case, provided an educated guess for the observed value of the sample proportion. For each exercise, a. obtain a sample size that will ensure a margin of error o

> Regarding a population proportion: a. What is it? b. What symbol is used for it?

> We have specified the margin of errors and confidence levels. Additionally, we have, in each case, provided an educated guess for the observed value of the sample proportion. For each exercise, a. obtain a sample size that will ensure a margin of error o

> We have specified the margin of errors and confidence levels. Additionally, we have, in each case, provided an educated guess for the observed value of the sample proportion. For each exercise, a. obtain a sample size that will ensure a margin of error o

> We have specified the margin of errors and confidence levels. Additionally, we have, in each case, provided an educated guess for the observed value of the sample proportion. For each exercise, a. obtain a sample size that will ensure a margin of error o

> Give an example, other than those presented in this section, of a a. qualitative variable. b. discrete, quantitative variable. c. continuous, quantitative variable.

> we have specified a margin of error and a confidence level. For each exercise, obtain a sample size that will ensure a margin of error of at most the one specified. margin of error = 0.04; confidence level = 99%

> we have specified a margin of error and a confidence level. For each exercise, obtain a sample size that will ensure a margin of error of at most the one specified. margin of error = 0.03; confidence level = 99%

> we have specified a margin of error and a confidence level. For each exercise, obtain a sample size that will ensure a margin of error of at most the one specified. margin of error = 0.01; confidence level = 90%

> we have specified a margin of error and a confidence level. For each exercise, obtain a sample size that will ensure a margin of error of at most the one specified. margin of error = 0.02; confidence level = 90%

> we have specified a margin of error and a confidence level. For each exercise, obtain a sample size that will ensure a margin of error of at most the one specified. margin of error = 0.02; confidence level = 95%

> we have specified a margin of error and a confidence level. For each exercise, obtain a sample size that will ensure a margin of error of at most the one specified. margin of error = 0.01; confidence level = 95%

> We have given the number of successes and the sample size for a simple random sample from a population. In each case, do the following tasks. a. Determine the sample proportion. b. Decide whether using the one-proportion z-interval procedure is appropria

> Is a population proportion a parameter or a statistic? What about a sample proportion? Explain your answers.

> We have given the number of successes and the sample size for a simple random sample from a population. In each case, do the following tasks. a. Determine the sample proportion. b. Decide whether using the one-proportion z-interval procedure is appropria

> We have given the number of successes and the sample size for a simple random sample from a population. In each case, do the following tasks. a. Determine the sample proportion. b. Decide whether using the one-proportion z-interval procedure is appropria

> In 1903, K. Pearson and A. Lee published the paper “On the Laws of Inheritance in Man. I. Inheritance of Physical Characters” (Biometrika, Vol. 2, pp. 357–462). The article examined and presented data on forearm length, in inches, for a sample of 140 men

> We have given the number of successes and the sample size for a simple random sample from a population. In each case, do the following tasks. a. Determine the sample proportion. b. Decide whether using the one-proportion z-interval procedure is appropria

> We have given the number of successes and the sample size for a simple random sample from a population. In each case, do the following tasks. a. Determine the sample proportion. b. Decide whether using the one-proportion z-interval procedure is appropria

> We have given the number of successes and the sample size for a simple random sample from a population. In each case, do the following tasks. a. Determine the sample proportion. b. Decide whether using the one-proportion z-interval procedure is appropria

> We have given a likely range for the observed value of a sample proportion p^. a. Based on the given range, identify the educated guess that should be used for the observed value of p to calculate the required sample size for a prescribed confidence leve

> We have given a likely range for the observed value of a sample proportion p^. a. Based on the given range, identify the educated guess that should be used for the observed value of p to calculate the required sample size for a prescribed confidence leve

> We have given a likely range for the observed value of a sample proportion p^. a. Based on the given range, identify the educated guess that should be used for the observed value of p to calculate the required sample size for a prescribed confidence leve

> We have given a likely range for the observed value of a sample proportion p^. a. Based on the given range, identify the educated guess that should be used for the observed value of p to calculate the required sample size for a prescribed confidence leve

> We have given a likely range for the observed value of a sample proportion p^. a. Based on the given range, identify the educated guess that should be used for the observed value of p to calculate the required sample size for a prescribed confidence leve

> Why is statistical inference generally used to obtain information about a population proportion?

> We have given a likely range for the observed value of a sample proportion p^. a. Based on the given range, identify the educated guess that should be used for the observed value of p to calculate the required sample size for a prescribed confidence leve

> A study by researchers at the University of Maryland addressed the question of whether the mean body temperature of humans is 98.6◦F. The results of the study by P. Mackowiak et al. appeared in the article “A Critical Appraisal of 98.6◦F, the Upper Limit

2.99

See Answer