Question: The following table lists the numbers of

> The results of my hypothesis test were statistically significant at the 0.01 level, so no one can doubt my claim any longer.

> A researcher conducts a hypothesis test to test the claim that a new drug is effective in lowering LDL cholesterol. The P-value for the test is 0.001, and the researcher claims that this supports the claim.

> To learn about smart phone ownership, I chose a null hypothesis claiming that the proportion of adults who own a smart phone is equal to 0.8, and the result of my hypothesis test proved this claim to be true.

> Our survey found that 56% of voters approve of a particular policy of the President, with a margin of error (for 95% confidence) of 4 percentage points. Therefore, there is only a 5% chance that the proportion of approval among all voters differs from 56

> Briefly describe how each of the following can be used to show multiple data sets: a multiple bar graph, a multiple line chart, and a stack plot. When is the stack plot most useful?

> Construct a stem plot of these test scores: 67, 72, 85, 75, 89, 89, 88, 90, 99, and 100. How does the stem plot show the distribution of these data?

> How can you determine an appropriate sample size for a study if you want a particular margin of error?

> Once you have constructed the 95% confidence interval around your sample proportion, what does this tell you about the estimated value of the population proportion?

> What is a census, what is a sample, and what is the difference between them?

> If you seek to construct a 95% confidence interval around your sample proportion, how do you calculate the margin of error that you will use? How do you then construct the 95% confidence interval?

> Suppose you conducted an opinion poll and measured the proportion of your sample that held a particular view. What value should you use as your estimate of the population proportion?

> Two thirds (or 66.6%) of 626 Colorado residents polled by Talmey Drake Research & Strategy Inc. said that they backed a bill pending in the legislature that would standardize laws on granting concealed weapon permits to gun owners. The bill would force l

> A poll finds that 54% of the population approves of the job that the President is doing; the poll has a margin of error of 4% (assuming a 95% confidence level). a. What is the 95% confidence interval for the true population percentage that approves of th

> The Bureau of Labor Statistics estimates the unemployment rate in the United States each month by surveying 60,000 individuals. a. In one month, 3.4% of the 60,000 individuals surveyed are found to be unemployed. Find the margin of error for this estimat

> Prior to a statewide election for the U.S. Senate, three polls are conducted. In the first poll, 780 of 1500 voters favor candidate Martinez. In the second poll, 1285 of 2500 voters favor Martinez. In the third poll, 1802 of 3500 voters favor Martinez. F

> The drug Eliquis is used to help prevent blood clots in certain patients. In clinical trials, among 5924 patients treated with Eliquis, 153 developed the adverse reaction of nausea (based on data from BristolMyers Squibb Co.). Construct a 95% confidence

> The following table lists labor force participation rates (as percentages) of mothers, categorized according to the age of their youngest child (based on data from the Bureau of Labor Statistics).

> A study by Stanford University researchers for the Office of National Drug Control Policy and the Department of Health and Human Services concluded that 98% of the top rental films involve drugs, drinking, or smoking. Assume that this study is based on t

> A Pew Research Center poll surveyed 1708 randomly selected adults who were asked whether “global warming is a problem that requires immediate government action.” Results showed that 939 of those surveyed indicated that immediate government action is requ

> The Genetics and IVF Institute conducted clinical trials of the YSORT method designed to increase the probability of conceiving a boy. Among 152 babies born to parents using the YSORT method, 127 were boys. Calculate the margin of error and the 95% confi

> In a Gallup poll of 1059 adults, the interview subjects were selected by using a computer to randomly generate telephone numbers (both land lines and cell phones) that were then called.

> In a study of the accuracy of order filling at fast food drive through, McDonald’s had 33 orders that were not accurately filled among 362 orders observed (based on data from QSR magazine). Calculate the margin of error and the 95% confidence interval fo

> A study done by researchers at Alfred University concluded that 80% of all student athletes in this country have been subjected to some form of hazing. The study is based on responses from 1400 athletes. What is the margin of error and the 95% confidence

> Repeat Exercise 21 assuming that the sample size is doubled to 10,000. Given that the large cost and effort of conducting the Nielsen survey would be doubled, does this increase in sample size appear to be justified by the increased reliability?

> Nielsen Media Research uses samples of 5000 households to rank TV shows. Nielsen reported that 60 Minutes had 15% of the TV audience. What is the 95% confidence interval for this result?

> Assume that you want to construct a 95% confidence interval to estimate a population mean. Find the minimum sample size needed to obtain the specified margin of error for the 95% confidence interval. E = 0.015

> Assume that you want to construct a 95% confidence interval to estimate a population mean. Find the minimum sample size needed to obtain the specified margin of error for the 95% confidence interval. E = 0.123

> The following table summarizes deaths due to firearms in different nations in a recent year (data from the Coalition to Stop Gun Violence).

> Assume that you want to construct a 95% confidence interval to estimate a population mean. Find the minimum sample size needed to obtain the specified margin of error for the 95% confidence interval. E = 0.025

> Assume that you want to construct a 95% confidence interval to estimate a population mean. Find the minimum sample size needed to obtain the specified margin of error for the 95% confidence interval. E = 0.03

> Assume that population proportions are to be estimated from the samples described. In each case, find the approximate margin of error and 95% confidence interval. n = 2250, p̂ = 0.853

> Assume that population proportions are to be estimated from the samples described. In each case, find the approximate margin of error and 95% confidence interval. n = 420, p̂ = 0.65

> A college dean obtains an alphabetical list of all full-time students at her college and she selects every 50th name on that list and interviews those students to find the amount of student debt incurred by each of them. She uses the results to estimate

> Assume that population proportions are to be estimated from the samples described. In each case, find the approximate margin of error and 95% confidence interval. Sample size, n = 1260; sample proportion, p̂ = 0.25

> Assume that population proportions are to be estimated from the samples described. In each case, find the approximate margin of error and 95% confidence interval. Sample size, n = 555; sample proportion, p̂ = 0.8

> In a Pew Research Center poll, 73% of 3011 adults surveyed said that they use the Internet. In this context, what are n, p ̂, and p?

> Here is a typical statement made by the media: “Based on a survey of 1068 likely voters, 56% favor the proposed environmental legislation, and this survey has a margin of error of 3 percentage points.” What important and relevant piece of information is

> In a study of 1228 randomly selected medical malpractice lawsuits, it is found that the proportion that were dropped or dismissed is 0.697. When a 95% confidence interval is constructed for the population proportion of all lawsuits, the margin of error i

> The following table gives the number of daily newspapers and their total circulation (in millions) for selected years since 1920 (from Editor& Publisher).

> The Journal of the American Medical Association published an article about a survey of adults and cited this 95% confidence interval for the proportion of adults who use at least one prescription medication: 0.803 < ρ < 0.831. Interpret that confidence i

> A reporter for the Kingston Chronicle claims that any good confidence interval should be based on a sample that is at least 5% of the population size.

> The Kingston Chronicle publishes an article stating that, based on survey results, 82% of Orange County residents oppose an increase in the sales tax, with a margin of error of 4 percentage points. We can therefore express the confidence interval as 0.78

> Our exit polls found that candidate Jones received 56% of the vote with a margin of error (for 95% confidence) of 5 percentage points, but the final results showed Jones with only 47% of the vote.

> Suppose you seek a particular margin of error for your study. How can you determine an appropriate sample size?

> A consumer researcher surveyed customers at a Macy’s store to obtain sample data consisting of the amount of credit card debt that each customer has.

> Once you have constructed the 95% confidence interval around your sample mean, how do you interpret its possible relationship to the population mean?

> If you seek to construct a 95% confidence interval to estimate a population mean, how do you calculate the margin of error that you will use? How do you then construct the 95% confidence interval?

> Suppose you have measured the mean in a sample drawn from a much larger population. What value should you use as your estimate of the population mean?

> A random sample of n = 31 American households is asked how many TV sets there are in the household. The responses are as follows: 1 0 2 3 2 3 4 2 1 1 2 4 3 2 3 3 0 1 0 1 3 2 4 3 2 1 4 0 1 2 3 a. What is the mean number of TVs for the sample? b. What is t

> One of the authors of this text counted the numbers of chocolate chips in 20 Chips Ahoy regular chocolate chip cookies, and the results are listed below. 22 22 26 24 23 27 25 20 24 26 25 25 19 24 20 22 24 25 25 20 a. What is the mean number of chocolate

> When people smoke, the nicotine they absorb is converted to cotinine, which can be measured. A sample of cotinine levels (ng/mL) of 40 smokers is listed below. Use a single value to estimate the mean amount of cotinine for all smokers. Find a 95% confide

> The health of the bear population in Yellowstone National Park is monitored by periodic measurements taken from anesthetized bears. A sample of the weights (in pounds) of such bears is given below. Use a single value to estimate the mean weight of all be

> Based on a sample of 62 households, the mean weight of discarded plastic is 1.91 pounds and the standard deviation is 1.07 pounds (data from the Garbage Project at the University of Arizona). Use a single value to estimate the mean weight of discarded pl

> Data from the National Center for Education Statistics on 4400 college graduates show that the mean time required to graduate with a bachelor’s degree is 5.15 years with a standard deviation of 1.68 years. Use a single value to estimate the mean time req

> A sample of 100 babies born at Strong Memorial Hospital has a mean weight of 3072 grams and a standard deviation of 748 grams. Use a single value to estimate the mean weight of a newborn baby. Also, find the 95% confidence interval.

> A marketing expert for MTV is planning a survey in which 500 people will be randomly selected from each age group: 10–19, 20–29, and so on.

> You want to estimate the mean weight of quarters in circulation. A sample of 40 quarters has a mean weight of 5.639 grams and a standard deviation of 0.062 gram. Use a single value to estimate the mean weight of all quarters. Also, find the 95% confidenc

> An economist wants to estimate mean annual income from the first year of work for college graduates who have had the profound wisdom to take a statistics course. How many such incomes must she find if she wants to be 95% confident that the sample mean is

> The Wechsler IQ test is designed so that the mean is 100 and the standard deviation is 15 for the population of normal adults. Find the minimum sample size necessary to estimate the mean IQ score of California residents if you want to be 95% confident th

> a. What percentage of students does not party at least 3 hours per week? b. The graphic shows two different percentages for categories that mention relevance of coursework. Is this a contradiction? Why or why not? Figure 3.19

> A government survey is to be conducted to estimate the mean price of houses in a large metropolitan area; it is designed to have a margin of error of E = $10,000. Pilot studies suggest that the population standard deviation is σ = $65,500. Calculate the

> Nielsen Media Research wishes to estimate the mean number of hours that high school students spend watching TV on a weekday. A margin of error of E = 0.25 hour is desired. Past studies suggest that a population standard deviation of σ = 1.7 hours is reas

> Margin of error, E = 20.3 cm; sample standard deviation, s = 321.0 cm

> Margin of error, E = 8.5 grams; sample standard deviation, s = 68.5 grams

> Margin of error, E = 1.5 meters; sample standard deviation, s = 30.6 meters

> Margin of error, E = 2.6 minutes; sample standard deviation, s = 45.4 minutes

> n = 60, x‾ = 112.2 volts, s = 4.4 volts

> An Internal Revenue Service researcher investigates false reporting of tip income by surveying all servers at 20 randomly selected restaurants.

> n = 36, x‾ = 60.9 seconds, s = 4.3 seconds

> Sample size, n = 49; sample mean, x̅ = 12.8 kilograms (kg); sample standard deviation, s = 2.5 kg

> a. Within a group of 500 typical first-year college students, approximately how many have loans to help pay for their education? b. Can you conclude that some students who are satisfied with their coursework also text in class? Explain. Figure 3.19

> Sample size, n = 100; sample mean, x̅  = 55.0 cm; sample standard deviation, s = 5.0 cm

> The National Health Examination involves measurements from about 25,000 people, and the results are used to estimate values of various population means. Is it valid to criticize this survey because the sample size is only about 0.01% of the population of

> Here is a typical statement made by the media: “Based on a recent study, pennies weigh an average of 2.5 grams with a margin of error of 0.006 gram.” What important and relevant piece of information is omitted from that statement? Is it acceptable to use

> Based on a random sample of 48 birth weights of girls born at Albany Medical Center Hospital, the sample mean is 2965 grams and the margin of error for a 95% confidence interval is 245 grams. Find the 95% confidence interval.

> One study involved a sample of people’s body temperatures and it resulted in this 95% confidence interval for the mean: 98.1 ⁰F

> Although it made our study more expensive, we chose a larger sample size in order to have a smaller margin of error.

> Based on our sample, the 95% confidence interval for the mean amount of television watched by adult Americans is 2.5 to 2.7 hours per day. Therefore, there is a 95% chance that the mean for all Americans will fall somewhere in this range and a 5% chance

> Based on our sample, the 95% confidence interval for the mean amount of television watched by adult Americans is 2.5 to 2.7 hours per day. Therefore, 95% of all Americans watch between 2.5 and 2.7 hours of TV per day. Answer: The statement does not ma

> An engineering student measures the strength of fingers used to push buttons by testing her own family members.

> Based on our sample, the 95% confidence interval for the mean amount of television watched by adult Americans is 2.5 to 2.7 hours per day. Therefore, there is 95% chance that the actual mean for the population is 2.6 hours.

> a. In about what year did (will) the population of 45- to 54-year-olds peak as a percentage of the population? b. In about what year did (will) the population of over 65-year-olds peak as a percentage of the population? c. Discuss any significant trends

> I selected three different samples of size n = 10 drawn from the 1500 students at my school, and with these I constructed the sampling distribution.

> How does the sample size affect how close to normal a distribution of either sample means or sample proportions will be? What are the means and standard deviations of the distributions in each case?

> What is a sample mean? What is a sample proportion? Summarize the notation used for these statistics.

> What is a sampling error? How does it differ from other sources of error? In general, how does the sampling error increase or decrease with larger sample sizes? Explain.

> Distinguish between a distribution of sample means and a distribution of sample proportions.

> When 650 adults are randomly selected, find the probability that 84 or more of them are left handed. Does the result of 84 left handed adults appear to be unusually high?

> If 820 adults are randomly selected, find the probability that 92 or more of them are left handed. Does the result of 92 left handed adults appear to be unusually high?

> If 250 adults are randomly selected, find the probability that 15 or fewer of them are left handed. Does the result of 15 left handed adults appear to be unusually low?

> If 500 adults are randomly selected, find the probability that 45 or fewer of them are left handed. Does the result of 45 left handed adults appear to be unusually low?

> A medical researcher is conducting a study to test the effectiveness of a drug designed to lower cholesterol levels. She randomly selects a sample of 100 males and 100 females.

> a. About what percentage of the population were over age 65 in 2010? b. About what percentage of the population is projected to be over age 65 in 2050? c. Describe the projected change in the 45&acirc;&#128;&#147;54 age groups between 2010 and 2050. Figu

> A random sample of 81 newborn girls is obtained and they have a mean birth weight of 2919 grams. What is the probability of randomly selecting another 81 newborn girls and getting a mean birth weight that is 2919 grams or less? Does it seem like a sample

> A random sample of 64 newborn girls is obtained and they have a mean birth weight of 3390 grams. What is the probability of randomly selecting another 64 newborn girls and getting a mean birth weight that is 3390 grams or more? Does it seem like a sample

> A random sample of 36 newborn girls is obtained and they have a mean birth weight of 3272˜ grams. What is the probability of randomly selecting another 36 newborn girls and getting a mean birth weight that is 3272 grams or more? Does it seem like a sampl

> A random sample of 100 newborn girls is obtained and they have a mean birth weight of 2966˜ grams. What is the probability of randomly selecting another 100 newborn girls and getting a mean birth weight that is 2966 grams or lower? Does it seem like a sa

> The ages (in years) of the four U.S. presidents when they were assassinated in office are 56(Lincoln), 49 (Garfield), 58 (McKinley), and 46 (Kennedy). Consider these four ages to be a population. a. Assuming that two of the ages are randomly selected to

> A quarterback threw 1 interception in his first game, 2 interceptions in his second game, and 5 interceptions in his third game, and then he retired. Consider the values 1, 2, and 5 to be a population. Assume that samples of size 2 are randomly selected

> The College of Portland has a total enrollment of N = 2444 students and 269 of them are left handed. You conduct a survey of n = 50 students and find that 8 of them are left handed. a. What is the population proportion, p, of left handed students? b. Wha