2.99 See Answer

Question: The Quinnipiac University Poll conducts nationwide


The Quinnipiac University Poll conducts nationwide surveys as a public service and for research. In one poll, participants were asked whether they thought eliminating the federal gas tax for the summer months is a good idea. The following problems are based on the results of that poll.
a. Of 611 Republicans, 275 thought it a good idea, and, of 872 Democrats, 366 thought it a good idea. Obtain a 90% confidence interval for the difference between the proportions of Republicans and Democrats who think that eliminating the federal gas tax for the summer months is a good idea.
b. Of 907 women, 417 thought it a good idea, and, of 838 men, 310 thought it a good idea. Obtain a 90% confidence interval for the difference between the percentages of women and men who think that eliminating the federal gas tax for the summer months is a good idea.


> 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

> According to an article in Science News, binge eating has been associated with a mutation of the gene for a brain protein called melanocortin 4 receptor (MC4R). In one study, F. Horber of the Hirslanden Clinic in Zurich and his colleagues genetically ana

> A Harris Poll asked Americans whether states should be allowed to conduct random drug tests on elected officials. Of 21,355 respondents, 79% said “yes.” a. Determine the margin of error for a 99% confidence interval. b. Without doing any calculations, in

> From the U.S. Census Bureau document America’s Families and Living Arrangements and an article in Time magazine, we found that, in 1963, 83.0% of American women between the ages of 25 and 54 were married, compared to 64.6% in 2010. a. For 2010, identify

> From Wikipedia’s on-line document “List of First Overall NBA Draft Picks,” we found that, since 1947, 10.4% of the number-one draft picks in the National Basketball Association have been other than U.S. nationals. a. Identify the population. b. Identify

> Prerequisite to this exercise are Exercises 11.9–11.13. What do your graphs in parts (c) of those exercises illustrate about the impact of increasing sample size on sampling error? Explain your answer. Data from Exercise 11.13: This exercise involves th

> Repeat Exercise 11.136 by applying the formula in Exercise 11.134(a) if you can reasonably presume that at most 41% of the men sampled and at most 49% of the women sampled will be people who sometimes order veg. Compare the results obtained in Exercise 1

> Refer to the study on ordering vegetarian. a. Without making a guess for the observed values of the sample proportions, find the common sample size that will ensure a margin of error of at most 0.01 for a 90% confidence interval. b. Find a 90% confidence

> Refer to the study on ordering vegetarian. a. Obtain the margin of error for the estimate of the difference between the proportions of men and women who sometimes order veg by taking half the length of the confidence interval found. Interpret your answer

> Suppose that you can make reasonably good educated guesses, pˆ1g and pˆ2g, for the observed values of pˆ1 and pˆ2. a. Use your result from Exercise 11.132 to show that a (1 − α)-level confidence interval for the difference between two population proporti

> Use your result from Exercise 11.132 to show that a (1 − α) level confidence interval for the difference between two population proportions that has a margin of error of at most E can be obtained by choosing rounded up to the nearest whole number.

> As reported by the U.S. Census Bureau in the document Educational Attainment in the United States, the percentage of adults in each state and the District of Columbia who have completed a bachelor’s degree is provided on the WeissStats site. a. use the t

> Obtain a formula for the margin of error, E, in estimating the difference between two population proportions by referring to Step 2 of Procedure.

> A Wall Street Journal article, titled “Hypertension Drug Linked to Cancer,” reported on a study of several types of high-blood-pressure drugs and links to cancer. For one type, called calcium channel blockers, 27 of 202 elderly patients taking the drug d

> Repeat parts (b)–(e) of Exercise 11.9 for samples of size 5. Data from Exercise 11.9: This exercise involves the use of an unrealistically small population to provide a concrete illustration for the exact distribution of a sample proportion. A populatio

> Use the two-proportions plus four z-interval procedure to find the required confidence interval. Interpret your results. The Organization for Economic Cooperation and Development (OECD) conducts studies on unemployment rates by country and publishes its

> Use the two-proportions plus four z-interval procedure to find the required confidence interval. Interpret your results. Since 1973, Gallup has asked Americans how much confidence they have in a variety of U.S. institutions. One question asked of those p

> x1 = 30, n1 = 80, x2 = 15, n2 = 20; 95% confidence interval a. use the two-proportions plus-four z-interval procedure to find the required confidence interval for the difference between the two population proportions. b. compare your result with the corr

> x1 = 18, n1 = 30, x2 = 10, n2 = 20; 95% confidence interval a. use the two-proportions plus-four z-interval procedure to find the required confidence interval for the difference between the two population proportions. b. compare your result with the corr

> x1 = 15, n1 = 20, x2 = 18, n2 = 30; 90% confidence interval a. use the two-proportions plus-four z-interval procedure to find the required confidence interval for the difference between the two population proportions. b. compare your result with the corr

> x1 = 14, n1 = 20, x2 = 8, n2 = 20; 90% confidence interval a. use the two-proportions plus-four z-interval procedure to find the required confidence interval for the difference between the two population proportions. b. compare your result with the corre

> As reported by the U.S. Census Bureau in Educational Attainment in the United States, the percentage of adults in each state and the District of Columbia who have completed high school is provided on the WeissStats site. a. use the technology of your cho

> x1 = 18, n1 = 40, x2 = 30, n2 = 40; 80% confidence interval a. use the two-proportions plus-four z-interval procedure to find the required confidence interval for the difference between the two population proportions. b. compare your result with the corr

> x1 = 10, n1 = 20, x2 = 18, n2 = 30; 80% confidence interval a. use the two-proportions plus-four z-interval procedure to find the required confidence interval for the difference between the two population proportions. b. compare your result with the corr

> In the New York Times article “College Graduates Fare Well in Jobs Market, Even through Recession,” C. Rampell noted that college graduates have suffered through the recession and lackluster recovery with remarkable resilience. Of a random sample of 1020

> Neutropenia is an abnormally low number of neutrophils (a type of white blood cell) in the blood. Chemotherapy often reduces the number of neutrophils to a level that makes patients susceptible to fever and infections. G. Bucaneve et al. published a stud

> Repeat parts (b)–(e) of Exercise 11.9 for samples of size 4. Data from Exercise 11.9: This exercise involves the use of an unrealistically small population to provide a concrete illustration for the exact distribution of a sample proportion. A populatio

> The Organization for Economic Cooperation and Development (OECD) summarizes data on labor-force participation rates in OECD in Figures. Independent simple random samples were taken of 300 U.S. women and 250 Canadian women. Of the U.S. women, 215 were fou

> An issue of Science News (Vol. 163, No. 22, pp. 341–342) reported that the Women’s Health Initiative cast doubts on the benefit of hormone-replacement therapy. Researchers randomly divided 4532 healthy women over the age of 65 years into two groups. One

> Apply Procedure to find the required confidence interval. Refer to Exercise 11.111 and find and interpret a 90% confidence interval for the difference between the percentages of adults in the two degree categories who have an above healthy weight. Data

> Apply Procedure to find the required confidence interval. Refer to Exercise 11.110 and find and interpret a 98% confidence interval for the difference between the percentages of women and men who favor ballistic fingerprinting. Data from Exercise 11.110

> Apply Procedure to find the required confidence interval. Refer to Exercise 11.109 and find and interpret a 99% confidence interval for the difference between the proportions of seat-belt users for drivers in the age groups 16–24 years and 25–69 years.

> In the article, “Length of The Beatles’ Songs” (Chance, Vol. 25, No. 1, pp. 30–33), T. Koyama discusses aspects and interpretations of the lengths of songs by The Beatles. Data on the length, in seconds, of 229 Beatles’ songs are presented on the WeissSt

> Apply Procedure to find the required confidence interval. Refer to Exercise 11.108 and find and interpret a 95% confidence interval for the difference between the stroke incidences of white and African-American elderly. Data from Exercise 11.108: In the

> Apply Procedure to find the required confidence interval. Refer to Exercise 11.107 and determine and interpret a 98% confidence interval for the difference between the rates of major birth defects for babies born to women who have taken folic acid and th

> Apply Procedure to find the required confidence interval. Refer to Exercise 11.106 and determine and interpret a 98% confidence interval for the difference between the prostate cancer rates of men who have had a vasectomy and those who have not. Data fr

> Body mass index (BMI) is a measure of body fat based on height and weight. According to the document Dietary Guidelines for Americans, published by the U.S. Department of Agriculture and the U.S. Department of Health and Human Services, for adults, a BMI

> Guns make unique markings on bullets they fire and their shell casings. These markings are called ballistic fingerprints. An ABCNEWS Poll examined the opinions of Americans on the enactment of a law “. . .that would require every gun sold in the United S

> Repeat parts (b)–(e) of Exercise 11.9 for samples of size 3. Data from Exercise 11.9: This exercise involves the use of an unrealistically small population to provide a concrete illustration for the exact distribution of a sample proportion. A populatio

> The National Highway Traffic Safety Administration collects data on seat-belt use and publishes results in the document Occupant Restraint Use. Of 1000 drivers 16–24 years old, 79% said that they buckle up, whereas 924 of 1100 drivers 25–69 years old sai

> In the paper “The Racial Crossover in Comorbidity, Disability, and Mortality” (Demography, Vol. 37(3), pp. 267–283), N. Johnson investigated the health of independent random samples of white and African-American elderly (aged 70 years or older). Of the 4

> For several years, evidence had been mounting that folic acid reduces major birth defects. A. Czeizel and I. Dudas of the National Institute of Hygiene in Budapest directed a study that provided the strongest evidence to date. Their results were publishe

> In the United States, approximately 450,000 vasectomies are performed each year. In this surgical procedure for contraception, the tube carrying sperm from the testicles is cut and tied. Several studies have been conducted to analyze the relationship bet

> In an article titled “Great White, Deep Trouble” (National Geographic, Vol. 197(4), pp. 2–29), Peter Benchley—the author of JAWS—discussed various aspects of the Great White Shark (Carcharodon carcharias). Data on the number of pups borne in a lifetime b

> In the 1940s and early 1950s, the public was greatly concerned about polio. In an attempt to prevent this disease, Jonas Salk of the University of Pittsburgh developed a polio vaccine. In a test of the vaccine’s efficacy, involving nearly 2 million grade

> x1 = 30, n1 = 80, x2 = 15, n2 = 20; two-tailed test, α = 0.05; 95% confidence interval We have provided the numbers of successes and the sample sizes for independent simple random samples from two populations. a. Determine the sample proportions. b. Deci

> x1 = 18, n1 = 30, x2 = 10, n2 = 20; two-tailed test, α = 0.05; 95% confidence interval We have provided the numbers of successes and the sample sizes for independent simple random samples from two populations. a. Determine the sample proportions. b. Deci

> x1 = 15, n1 = 20, x2 = 18, n2 = 30; right-tailed test, α = 0.05; 90% confidence interval We have provided the numbers of successes and the sample sizes for independent simple random samples from two populations. a. Determine the sample proportions. b. De

> x1 = 14, n1 = 20, x2 = 8, n2 = 20; right-tailed test, α = 0.05; 90% confidence interval We have provided the numbers of successes and the sample sizes for independent simple random samples from two populations. a. Determine the sample proportions. b. Dec

> x1 = 18, n1 = 40, x2 = 30, n2 = 40; left-tailed test, α = 0.10; 80% confidence interval We have provided the numbers of successes and the sample sizes for independent simple random samples from two populations. a. Determine the sample proportions. b. Dec

> x1 = 10, n1 = 20, x2 = 18, n2 = 30; left-tailed test, α = 0.10; 80% confidence interval We have provided the numbers of successes and the sample sizes for independent simple random samples from two populations. a. Determine the sample proportions. b. Dec

> Repeat parts (b)–(e) of Exercise 11.9 for samples of size 1. Data from Exercise 11.9: This exercise involves the use of an unrealistically small population to provide a concrete illustration for the exact distribution of a sample proportion. A populatio

> An independent golf equipment testing facility compared the difference in the performance of golf balls hit off a regular 2-3/4’’ wooden tee to those hit off a 3’’ Stinger Competition golf tee. A Callaway Great Big Bertha driver with 10 degrees of loft w

> L. Petersen et al. evaluated the effects of integrated treatment for patients with a first episode of psychotic illness in the paper “A Randomised Multicentre Trial of Integrated Versus Standard Treatment for Patients with a First Episode of Psychotic Il

> We conducted a non-pooled t-test, at the 5% significance level, to decide whether the mean operative time is less with the dynamic system than with the static system. Use the technology of your choice to perform the following tasks. a. Using a pooled t-t

> In the article “Trophic Interaction Cycles in Tundra Ecosystems and the Impact of Climate Change”, R. Ims and E. Fuglei provided an overview of animal species in the northern tundra. One threat to the snow goose in arctic Canada is the lemming. Snowy owl

> You conducted a non-pooled t-test to decide whether the mean number of acute postoperative days spent in the hospital is smaller with the dynamic system than with the static system. Use the technology of your choice to perform the following tasks. a. Usi

> A mutual fund is a professionally managed investment that can be sold to the general public. Mutual funds can be specialized into different categories such as healthcare-related or technology-related mutual funds. The following table lists the 3-month ra

> L. Grossback et al. examined mandate perceptions and their causes in the paper “Comparing Competing Theories on the Causes of Mandate Perceptions” (American Journal of Political Science, Vol. 49, Issue 2, pp. 406–419). The following are data on the perce

> In the article “Sleep Apnea in Adults With Traumatic Brain Injury: A Preliminary Investigation” (Archives of Physical Medicine and Rehabilitation, Vol. 82, Issue 3, pp. 316– 321), J. Webster et al. investigated sleep-related breathing disorders in adults

> Refer to Exercise 10.86 and find a 99% confidence interval for the difference between the mean wing lengths of the two subspecies. Data from Exercise 10.86: D. Cristol et al. published results of their studies of two subspecies of dark-eyed juncos in th

> Refer to Exercise 10.85 and determine a 98% confidence interval for the difference between the mean dopamine activities of psychotic and nonpsychotic patients. Data from Exercise 10.85: Previous research has suggested that changes in the activity of dop

> Refer to Exercise 10.84 and find a 90% confidence interval for the difference between the mean heart rates of urban bus drivers in Stockholm in the two environments. Data from Exercise 10.84: An intervention program designed by the Stockholm Transit Dis

> The primary concern is deciding whether the mean of Population 1 is less than the mean of Population 2. a. Determine the null and alternative hypotheses. b. Classify the hypothesis test as two tailed, left tailed, or right tailed.

> Refer to Exercise 10.83 and find a 90% confidence interval for the difference between the mean numbers of acute postoperative days in the hospital with the dynamic and static systems. Data from Exercise 10.83: The researchers also obtained the following

2.99

See Answer