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Answer Preview: Answer 1 Option B is correct Simple random sample 2 Option A is correct The procedure is likely to y…

, Chapter: 8 -Problem: 2 >> 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?
Answer Preview: Suppose we want to generate a 95 confidence interval estimate for an unknow…

, Chapter: 3 -Problem: 7 >> A quality control engineer wants to draw attention to the car parts that require repair most often, so she uses a Pareto chart to illustrate the frequencies of repairs for the various car parts.Does It Make Sense? For Exercises, determine whether the statement makes sense (or is clearly true) or does not make sense (or is clearly false). Explain clearly. Not all of these statements have definitive
Answer Preview: Yes it makes sense The 80 20 rule says that 20 percent of the car parts account for 80 percent of th…

, Chapter: 1 -Problem: 29 >> Does listening to Beethoven make teenagers more intelligent?
Answer Preview: Listening to classical music has not been shown to i…

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, Chapter: 7 -Problem: 5 >> I created a scatterplot of CEO salaries and corporate revenue for 10 companies and found a negative correlation, but when I left out a data point for a company whose CEO took no salary, there was no correlation for the remaining data.
Answer Preview: The CEO salaries were from the Forbes list of top 500 US companies and the corporate revenue figures …

, Chapter: 1 -Problem: 47 >> Find a recent news report about an opinion poll carried out by a news organization (such as Gallup, Harris, USA Today, New York Times, or CNN). Briefly describe the sample and how it was chosen. Was the sample chosen in a way that was likely to introduce any bias? Explain.
Answer Preview: Agencies conducting an exit poll follow a range of different proced…

, Chapter: 8 -Problem: 10 >> A college has 3427 enrolled students. When 50 of them were randomly selected for a survey, it was found that 10% of them were in favor of fees for parking permits.Notation. In Exercise, identify the notation for each given number.
Answer Preview: 3427 is the population size 50 is the sample size 10 for 10 o…

, Chapter: 6 -Problem: 29 >> What is the probability of randomly selecting a person and getting someone who does not have type O blood, given that 45% of people have type O blood?Complementary Events. Exercises involve complementary events. In each exercise, find the probability of the given event. State any assumptions that you use.
Answer Preview: P 45 gives the probability of randomly selecting a person and getting someone who does not have type …

, Chapter: 2 -Problem: 5 >> A survey asked people about their party affiliation and recorded the responses as 1 for Democrat, 2 for Republican, 3 for Independent, and 4 for anything else. The survey found that the average (mean) party affiliation is 2.5. Does It Make Sense? For, determine whether the statement makes sense (or is clearly true) or does not make sense (or is clearly false). Explain clearly; not all of these hav
Answer Preview: In the given statement we are asking people about their party affiliation and give them numbers S…

, Chapter: 7 -Problem: 8 >> In seeking to understand the factors that affect a college graduate’s future income, researchers conducted a multiple regression analysis that examined the effects of major, grade point average, the ranking of the college, parental affluence, and parental education.Does It Make Sense? For Exercises, determine whether the statement makes sense (or is clearly true) or does not make sense (or is clea
Answer Preview: It makes sense Excluding parental education and parental i…

, Chapter: 2 -Problem: 25 >> Twenty-five people, including yourself, are to measure the length of a room to the nearest tenth of a millimeter. Assume that everyone uses the same well-calibrated measuring device, such as a tape measure.a. All 25 measurements are not likely to be exactly the same; some will be higher than the true value and some lower. Do these differences represent systematic or random errors? Explain.b. If yo
Answer Preview: Here there are 25 people who will measure the length of the room to the nearest ten mm using a well …

, Chapter: 1 -Problem: 6 >> Consumer Reports rated house paints according to how well they hold up to hot weather by conducting an experiment in which they applied the various paints to identical surfaces that were then left exposed to the same hot weather conditions for the same length of time. But I don’t believe their results, because they did not consider how much the paints cost.
Answer Preview: Solution Consumer Reports rated house paints according to how well they hold …

, Chapter: 4 -Problem: 2 >> A professional soccer player is given a test for a banned substance. What does it mean when she is told that the result is positive? Do we know from such a positive result whether the player actually used the banned substance?
Answer Preview: A professional soccer player is given a test for a banned substance What does it mean when she is to…

, Chapter: 9 -Problem: 2 >> Why is the method discussed in this section referred to as one-way analysis of variance? That is, what is “one-way” about the method?
Answer Preview: It may seem odd that the technique is called Analysis of Variance rather than …

, Chapter: 7 -Problem: 5 >> Refer again to the scatterplot in Figure 7.24. Does there appear to be a significant correlation between the two variables? Figure 7.24 Transcribed Image Text: 10 -5 -10 0 1 7. 2 3 4 5 6 8
Answer Preview: First put the data in Excel sheet Here y growth is dependent variable X Trade share is indepe…

, Chapter: 1 -Problem: 13 >> A pollster for the U.S. Department of Labor surveys 1500 randomly selected adults about their employment status.
Answer Preview: The given information is that the pollster for the U S department of labor surveys 1 500 ad…

, Chapter: 1 -Problem: 33 >> A market researcher surveys 50 randomly selected drivers from each state and obtains the amount that they paid for a gallon of gas at their most recent purchase.
Answer Preview: For each state of America a market researcher surveys 50 randomly selected drivers and …

, Chapter: 7 -Problem: 23 >> 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 mean of 3390 grams is unusual?
Answer Preview: The mean birth weight of the sample is 3390 grams The population standard deviatio…

, Chapter: 7 -Problem: 4 >> If a correlation is very strong, can we conclude that one variable causes a change in the other variable? Why or why not?
Answer Preview: If a correlation is very strong can we conclude that one variable causes a change …

, Chapter: 2 -Problem: 3 >> Distinguish between accuracy and precision. Give an example of a measurement that is precise but inaccurate and another example of a measurement that is accurate but imprecise.
Answer Preview: Accuracy refers to the degree of conformity and correctness of something when compared to a true or …

, Chapter: 3 -Problem: 32 >> Find a recent news article that includes a pie chart. Briefly discuss the effectiveness of the pie chart. For example, would it be better if the data were displayed in a bar graph rather than a pie chart? Could the pie chart be improved in other ways?
Answer Preview: Pie charts are probably better than any other visual for expressing a part to whole relationship Whe…

, Chapter: 8 -Problem: 20 >> Margin of error, E = 20.3 cm; sample standard deviation, s = 321.0 cmSample Sizes. In Exercise, assume that you want to construct a 95% confidence interval estimate of a population mean. Find an estimate of the minimum sample size needed to obtain the specified margin of error for the 95% confidence interval. The sample standard deviation is given.
Answer Preview: The formula for the margin of error is Since we are interested in a 95 confidenc…

, Chapter: 7 -Problem: 3 >> What does the square of the correlation coefficient, r2, tell us about a best-fit line?
Answer Preview: What the square of the correlation coefficient r2 tell us about a best fit line is that it represent…

, Chapter: 1 -Problem: 6 >> Is this an experiment or an observational study?
Answer Preview: 1 Observational Study In this type of study we measure or survey members of a sample without trying …

, Chapter: 1 -Problem: 24 >> In one of Mendel’s famous genetics experiments that he conducted with peas, he obtained a sample of offspring peas consisting of 428 green peas and 152 yellow peas. Based on his theories, he expected that 25% of the offspring peas would be yellow.
Answer Preview: One sample of offspring consist of green peas 428 On…

, Chapter: 8 -Problem: 9 >> For a random sample of 575 randomly selected car batteries, it was found that their output had a mean of 12.2?volts and a standard deviation of 1.4 volts.Notation. In Exercise, identify the notation for each given number.
Answer Preview: 1 The notation for 12 2 volts is Mean centre of distribution of sample 12…

, Chapter: 6 -Problem: 32 >> The New England College of Medicine uses an admissions test with many multiple-choice questions, each with five possible answers, only one of which is correct. If you guess randomly on every question, what score might you expect to get? (Express the answer as a percentage.)
Answer Preview: The New England College of Medicine uses an admissions test with many multiple choice questions each …

, Chapter: 1 -Problem: 19 >> Hundreds of separate and individual scientific and statistical studies have been done to determine whether high-voltage overhead power lines increase the incidence of cancer among those living nearby. A summary study based on many previous studies concluded that there is no significant link between power lines and cancer (Journal of the American Medical Association).
Answer Preview: Determining the optimal sample size for a study assures an adequate power …

, Chapter: 1 -Problem: 38 >> Search through recent newspapers or journals and find an example of a statistical study that involved an experiment. Briefly describe the study and summarize its conclusions.
Answer Preview: Search through recent newspapers or journals and find an example of a statistical study that involved an experiment Briefly describe the study and sum…

, Chapter: 8 -Problem: 13 >> In a clinical trial, 11,000 male physicians were treated with aspirin and another 11,000 male physicians were given a placebo. A variable of interest was the proportion of heart attacks among the physicians. Do the results from this study apply to females? Why or why not?
Answer Preview: Yes it does apply to females This study was conducted precise…

, Chapter: 6 -Problem: 28 >> Based on current life expectancy data, to what age is the average 80-year-old expected to live?Life in This Century. Example 5 assumed that the life expectancy between 2000 and 2100 would increase by the same absolute amount as it did between 1900 and 2000. For women, life expectancy in the 20th century increased 32 years, and for men, it increased 28 years. For Exercises 29 and 30, suppose instea
Answer Preview: Calculations The age that the average 80 year old expected to live is given by E t …

, Chapter: 2 -Problem: 2 >> What is the Consumer Price Index (CPI)? How is it supposed to be related to inflation?
Answer Preview: Ans Consumer Price Index CPI The Consumer Price Index CPI is an index that is often used to measure …

, Chapter: 4 -Problem: 2 >> Briefly distinguish between the following measures of variation: range, five-number summary, and standard deviation. Which one(s) can be represented with a boxplot?
Answer Preview: Briefly distinguish between the following measures of variation range five number summary and standa…

, Chapter: 8 -Problem: 8 >> Our study measured the birth weights and incidence of jaundice among a sample of babies born at our hospital, and we found x = 6.7 pounds and pn = 0.45, or 45% showed signs of jaundice.
Answer Preview: That means here X no of babies with jaundice at birth ti…

, Chapter: 2 -Problem: 24 >> The times (years) it takes college students to earn a bachelor’s degree, such as 4 years, 412 years, 5 years, and so on.Discrete or Continuous. In Exercises, state whether the data described are discrete or continuous, and explain why.
Answer Preview: The times years it takes college students to earn a bac…

, Chapter: 1 -Problem: 1 >> Consider some of the results that are likely to come from the Harvard Nurses’ Health Study over the next 10 to 20 years. What types of results do you think will be most important? Do you think the findings will alter the way you live your life?
Answer Preview: The Nurses Health Study is a series of outlook studies that examine medical and the long term effect…

, Chapter: 4 -Problem: 5 >> For a recent year, baseball salaries had a median of $1,650,000 and a first quartile (Q1) of $1,675,000. Does It Make Sense? For Exercises, determine whether the statement makes sense (or is clearly true) or does not make sense (or is clearly false). Explain clearly; not all of these statements have definitive answers, so your explanation is more important than your chosen answer.
Answer Preview: The statement does not make sense Baseball salaries have a median of 1 650 000 and a …

, Chapter: 9 -Problem: 2 >> When testing a claim about a population mean, what is a standard score for the sample mean?
Answer Preview: When testing a claim about the value of a population mea…

, Chapter: 6 -Problem: 28 >> What is the probability of finding that the next President of the United States was not born on Saturday?Complementary Events. Exercises involve complementary events. In each exercise, find the probability of the given event. State any assumptions that you use.
Answer Preview: Let us assume that the chance of being born on Saturday is 0 6 t…

, Chapter: 1 -Problem: 22 >> An experiment conducted at Pennsylvania State University was designed to evaluate the effects of irrigation and fertilizers on poplar tree growth. Two different sites were used: (1) rich and moist; (2) sandy and dry. Each of the two sites were partitioned into four blocks, and each block was given one of the following: (1) No treatment(2) Fertilizer(3) Irrigation(4) Fertilizer and irrigation.
Answer Preview: An experiment conducted at Pennsylvania State University was designed to evaluate the effects of irr…

, Chapter: 1 -Problem: 46 >> Find a recent news report about a statistical study that you find interesting. Write a short summary of how the sample for the study was chosen, and briefly discuss whether you think the sample was representative of the population under study.
Answer Preview: Statistics is the application of mathematical concepts to understand…

, Chapter: 8 -Problem: 6 >> A random sample of 235 females and 240 males is obtained for a clinical trial. Construct a 95% confidence interval to estimate the proportion of females in all such samples.
Answer Preview: Sample proportion of females 235 235 240 0 …

, Chapter: 7 -Problem: 2 >> Which of the following are likely to have a correlation?a. Amounts donated to charities in a year and annual incomesb. Hat sizes and annual incomes of randomly selected adultsc. Braking reaction times and weights of randomly selected adultsd. Height and arm span of randomly selected subjectse. Value of cars owned and annual income of randomly selected car owners
Answer Preview: Which of the following are likely to have a correlation a Amounts donated to charities in a year and …

, Chapter: 1 -Problem: 5 >> All of the participants in the Harvard Nurses’ Health Study were women. Do you think that the results also are of use to men? Why or why not?
Answer Preview: In my judgement the results also are of use to men to some extent and to some extent they are not Be…

, Chapter: 2 -Problem: 7 >> Los Angeles reached a temperature of 100°F today, which was twice as hot as the 50°F in Denver.Does It Make Sense? For Exercises, determine whether the statement makes sense (or is clearly true) or does not make sense (or is clearly false). Explain clearly; not all of these have definitive answers, so your explanation may be more important than your chosen answer.
Answer Preview: The Statement doesn t make sense Temperature scales doesn t have true zero Thus we cannot compare …

, Chapter: 7 -Problem: 9 >> Based on what you’ve learned about the cause of global warming and its potential consequences, what do you think we should be doing about it, if anything?
Answer Preview: The causes of global warming include Increase in greenhouse gases and combustion of fossil fu…

, Chapter: 1 -Problem: 2 >> Explain why the Harvard Nurses’ Health Study is an observational study. Critics sometimes say that the results would be more valid if obtained by experiments rather than observations. Discuss whether it would be possible to gather similar data by carrying out experiments in a practical and ethical way.
Answer Preview: It is an observational study because they are taking surveys and then compiling the data into prac…

, Chapter: 2 -Problem: 10 >> Express the following numbers in the three forms of fraction, decimal, and percentage.a. 275% b. 3.75 c. 0.45 d. 90%
Answer Preview: Solution A decimal form 2 75 Frac…

, Chapter: 8 -Problem: 6 >> Do you believe that statistical analysis is useful for identifying authors of “lost works”?
Answer Preview: Sometimes you just plain cant There are even today arguments about several plays that are attributed to Shakespeare by scholars and disputed by others …

, Chapter: 1 -Problem: 3 >> In principle, the Harvard Nurses’ Health Study is subject to participation bias because only 120,000 of the original 370,000 questionnaires were returned. Should the researchers be concerned about this bias? Why or why not?
Answer Preview: Ans The researchers should be concerned about the bias One can ignore the bias …

, Chapter: 2 -Problem: 8 >> I used a meter stick to measure the length of my bed to the nearest micrometer.
Answer Preview: Units of Length Conversion 1 meter m 10 Decimeters dm 1 meter m 100 …

, Chapter: 9 -Problem: 2 >> Identify the null and alternate hypotheses for testing the claim that the proportion of college graduates who got a job within one month of graduation is greater than 0.4.
Answer Preview: The actual test begins by considering tw…

, Chapter: 1 -Problem: 8 >> The Department of Transportation used a retrospective study to determine that airbags save lives.
Answer Preview: Airbags protect you and your passengers from impact and injury Since 1999 all cars …

, Chapter: 1 -Problem: 32 >> 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.
Answer Preview: In a Gallup poll of 1059 adults the interview subjects were selected by using a c…

, Chapter: 7 -Problem: 18 >> The College of Portland has a total enrollment of N = 2444 students and 269 of them are lefthanded. You conduct a survey of n = 50 students and find that 8 of them are lefthanded.a. What is the population proportion, p, of left-handed students? b. What is the sample proportion, pn, of left-handed students? c. If the sample proportion differs from the population proportion by a large amount, does t
Answer Preview: a p 269 2444 0 11 b p hat …

, Chapter: 1 -Problem: 14 >> Consider a survey of randomly selected people in which it is found that participants who used sunscreen were more likely to have been sunburned in the past year. Which explanation for this result seems most likely? (a) Sunscreen is useless;(b) Tthe people in this study all used sunscreen that had passed its expiration date; (c) People who use sunscreen are more likely to spend time in the sun.
Answer Preview: Consider a survey of randomly selected people in which it is found that particip…

, Chapter: 2 -Problem: 9 >> An IRS agent reviews tax returns to identify the following:(1) mistakes made in calculations and (2) incorrect entries that were intentionally made to lower the tax bill. Discuss whether each problem involves random or systematic errors.
Answer Preview: Ans 1 Random because they represent an unpredictable event in the measurement p…

, Chapter: 7 -Problem: 10 >> A college has 3427 enrolled students. When 50 of them were randomly selected for a survey, it was found that 10% of them were in favor of fees for parking permits.
Answer Preview: Building 4 You can pay fees online with a credit card throu…

, Chapter: 1 -Problem: 14 >> A study of 2500 fatal car crashes identified those that involved drivers who were texting and those who were not.
Answer Preview: The numbers illustrating the dangers of cell phone use while driving are downright startling In fact …

, Chapter: 4 -Problem: 1 >> Consider two grocery stores at which the mean waiting time in line is the same but the variation of waiting times is different. At which store would you expect the customers to have more complaints about the waiting time?Explain.
Answer Preview: Consider two grocery stores at which the mean waiting time in line is the same but the variation of …

, Chapter: 7 -Problem: 25 >> If 500 adults are randomly selected, find the probability that 45 or fewer of them are lefthanded.Does the result of 45 lefthanded adults appear to be unusually low?
Answer Preview: A new study suggests lefties are rare because of the balance between cooperation and competition in …

, Chapter: 1 -Problem: 13 >> Consider a study in which you measure the weights of dolphins. The variable of interest in this study is: (a) The size of the sample(b) The weights of dolphins(c) The average (mean) weight of all dolphins.
Answer Preview: Imagine there exists a population of 10 000 dolphins and the mean weight of a dolphin in this popula…

, Chapter: 3 -Problem: 34 >> Find a recent news article that includes a line chart. Briefly explain what the line chart shows, and discuss whether it helps make the point of the news article. Are the labels clear? Is the line chart a time-series graph? Explain.
Answer Preview: The recent news article that includes a line chart is the Scholarly Metrics Show Why Wikipedia Is Lo…

, Chapter: 8 -Problem: 8 >> Although it made our study more expensive, we chose a larger sample size in order to have a smaller margin of error.Does It Make Sense? For Exercises, determine whether the statement makes sense (or is clearly true) or does not make sense (or is clearly false). Explain clearly. Not all of these statements have definitive answers, so your explanation is more important than your chosen answer
Answer Preview: The statement we chose a larger sample size in order …

, Chapter: 1 -Problem: 10 >> Tempered glass is used for car windows because it is much tougher than regular glass. A researcher tests the strength of samples of glass by heating them at 620°C, which is the industry standard.
Answer Preview: Soda lime glass starts to soften when it is heated to a temperature of more than 650C a fact that ca…

, Chapter: 2 -Problem: 14 >> A New York Times editorial criticized a chart caption that described a dental rinse as one that “reduces plaque on teeth by over 300%.” If the dental rinse removes all of the plaque, what percentage is removed? Is it possible to reduce plaque by over 300%?
Answer Preview: If the dental rinse removes all the plaques 1…

, Chapter: 9 -Problem: 1 >> What is a hypothesis in statistics? What do we mean by a hypothesis test in statistics?
Answer Preview: Hypothesis testing is an act in statistics whereby an analyst tests an assumption regarding a …

, Chapter: 2 -Problem: 2 >> Discuss the chart in Figure 2.4b. Why does it show actual incomes rather than incomes as a percentage of all taxpayers? What does it tell us about the effects of the tax cuts on each income level? Do you think it supports the claim in its title? Defend your opinion.Figure 2.4b Transcribed Image Text:
Answer Preview: It shows actual incomes rather than incomes as a percentage of all taxpayers because it is a snapsho…

, Chapter: 4 -Problem: 3 >> As this text goes to press, the government is considering but has not yet made a change to using the chained CPI. Has such a change happened yet? Investigate the current status of the debate over replacing the standard CPI with the chained CPI for the purposes of setting tax rates and cost-of-living adjustments.
Answer Preview: The change to using the chained CPI to calculate inflation has been proposed by previous administrations Democratic and Republican The change would ha…

, Chapter: 1 -Problem: 3 >> What is a biased sample, and what is a major problem with it?
Answer Preview: A biased sample is a sample where the members of the sample differ in some specific way from …

, Chapter: 2 -Problem: 5 >> Congress and the President are almost always proposing new changes in tax laws. Research one recent proposed change, providing a brief summary of the proposal and of the arguments for and against it. Do you personally support the proposal? Why or why not?
Answer Preview: For our country taxes are very important thing or for the they need to make new tax laws Taxes are c…

, Chapter: 1 -Problem: 10 >> You want to determine the mean weight of all high school football players in the state of California.
Answer Preview: For the first example the local high school football team probably isn t that huge Even if t…

, Chapter: 2 -Problem: 9 >> If you spent $12,250 for goods, services, and housing in 2015, what would the same purchases have cost in 2000?Consumer Price Index. In Exercises, use the Consumer Price Index values from Table 2.2. Transcribed Image Text: TABLE 2.2 Average Annual Consumer Price Index (1982–1984 = 100) Year CPI Year
Answer Preview: solution9 value of goods and …

, Chapter: 2 -Problem: 2 >> Distinguish between discrete and continuous data, and give an example of each.
Answer Preview: Discrete data refers to those which can take only intege…

, Chapter: 2 -Problem: 12 >> A study was conducted to determine whether flipping a penny or spinning a penny has an effect on the proportion of heads. Among 49,437 trials, 29,015 involved flipping pennies, and 14,709 of those pennies turned up heads. The other 20,422 trials involved spinning pennies, and 9,197 of those pennies turned up heads (based on data from Robin Lock, as given in Chance News).a. What percentage of the t
Answer Preview: Note It s amazing how lazy some people are i e the other person o…

, Chapter: 1 -Problem: 9 >> The Nielsen company installs devices in homes to record the TV shows that are watched. The results are then used to provide ratings identifying which shows are being viewed more than others.
Answer Preview: Television advertising is an incredibly lucrative industry in the U…

, Chapter: 1 -Problem: 30 >> Does the herb echinacea help prevent colds?
Answer Preview: Extracts of echinacea do seem to have an effect on the immune …

, Chapter: 1 -Problem: 3 >> Suppose that 5% of the 500 survey participants use a “password.” Is the value of 5% a sample statistic or a population parameter?
Answer Preview: Household surveys are among three major sources of social and demographic statistics in many countri…

, Chapter: 1 -Problem: 44 >> Use the Bureau of Labor Statistics website to find details on how the bureau chooses the sample of households in its monthly survey. Write a short summary of the procedure. What is the sample size? If the sample size is very large, does that compensate for having a biased sample?
Answer Preview: Answer Using the U S Bureau of Labor Statistics website I found that they use the Current Population …

, Chapter: 2 -Problem: 1 >> Distinguish between random errors and systematic errors. How can we minimize the effects of random errors? How can we account for the effect of a³ systematic error?
Answer Preview: A Jandom errors occurs because of unpredictable disturbances caused by the unknown Sourc…

, Chapter: 1 -Problem: 42 >> You want to determine the average (mean) error of aircraft altimeters when they are tested at a simulated altitude of 1000 feet.a. What could be a potential problem with a systematic sample obtained by selecting every 500th altimeter as the devices come off the assembly line?b. What could be a potential problem with a simple random sample of 5 altimeters?
Answer Preview: a 1000 ft 400 ft min 400 s or 0 4 hr Solution b Determine the probability that in a population of 20 …

, Chapter: 1 -Problem: 12 >> From the poll results given in Exercise 11, can we safely conclude that the majority of people are most annoyed by the use of “whatever” in conversation? Exercise 11In a Marist Poll, respondents chose the most annoying phrases used in conversation. Among the 864 subjects who were surveyed, 51% chose “whatever.” The survey has a margin of error of 3 percentage points. Identify the range of values f
Answer Preview: Exercise 11 In a Marist Poll respondents chose the most annoying phrases used in conversation Among …

, Chapter: 2 -Problem: 7 >> My bank raised its interest rate on savings accounts from 1% to 1.5%, which was a 50% increase.Does It Make Sense? For Exercises, determine whether the statement makes sense (or is clearly true) or does not make sense (or is clearly false). Explain clearly; not all of these have definitive answers, so your explanation is more important then your chosen answer.
Answer Preview: It does make sense because when my bank raised its …

, Chapter: 1 -Problem: 2 >> What method of sampling is used if 10 Internet users are randomly selected from each of the 50 states?
Answer Preview: I am confused about the meaning of sample size and what sampling method I used in my study My unders…

, Chapter: 1 -Problem: 36 >> It sometimes happens that the study is stopped early before its completion. Use the Internet to find an example of such a study. Why was the study stopped? Should it have been stopped, or would it be better to complete the study?
Answer Preview: One of the best things about life is that we never have to stop learning There are alway…

, Chapter: 1 -Problem: 11 >> In a Marist Poll, respondents chose the most annoying phrases used in conversation. Among the 864 subjects who were surveyed, 51% chose “whatever.” The survey has a margin of error of 3 percentage points. Identify the range of values for the confidence interval.
Answer Preview: In a Marist Poll respondents chose the most annoying phrases used in conversation Among the 864 subj…

, Chapter: 2 -Problem: 6 >> Recorded survey results include the states in which respondents reside. Are those data considered quantitative or qualitative, and what is their level of measurement (nominal, ordinal, interval, or ratio)?
Answer Preview: Agencies initiating a new survey or major revision of an existing …

, Chapter: 1 -Problem: 1 >> Identify the population and the sample.
Answer Preview: First your sample is the group of individuals who actually participate in your study These are the individuals who you end up interviewing e g in a qu…

, Chapter: 2 -Problem: 10 >> In a simple random sample of adults, the pulse rate is measured for each subject.Qualitative versus Quantitative Data. In Exercises, determine whether the data described are qualitative or quantitative, and explain why.
Answer Preview: Here hypothetical population means 5 4 Sample mean 5 25 Popu…

, Chapter: 2 -Problem: 1 >> Discuss the chart in Figure 2.4a. Why does it only show taxpayer income levels from the top 1% to the top 25%? What does it tell us about the relative tax burden on each group shown? Do you think its claim that the “rich pay more” is an honest depiction or a distortion of the facts? Defend your opinion.Figure 2.4a Transcri
Answer Preview: After looking to the chart Why does it show only upto 25 of the bars Answer If you see the numbers g…

, Chapter: 4 -Problem: 3 >> Briefly describe how you find quartiles and percentiles for a data set.
Answer Preview: To calculate quartiles and percentiles the data must be …

, Chapter: 1 -Problem: 15 >> Monsanto hires independent university scientists to determine whether its new, GMO (genetically modified organism) soybean poses any threat to consumers.
Answer Preview: The genetic makeup of a soybean gives it a wide variety of uses thus keeping it i…

, Chapter: 1 -Problem: 43 >> Use information available on the website of a polling organization, such as Gallup, Harris, Pew, or Yankelovich, to answer the following questions.a. How exactly is a sample of subjects selected? b. Based on what you have learned, do you think the poll results are reliable? If so, why? If not, why not?
Answer Preview: Answer a The sample is selected using a process called Probability Sampling in which …

, Chapter: 5 -Problem: 5 >> A process consists of repeating this operation: Randomly select two values from a normally distributed population and then find the mean of the two values. The sample means will be normally distributed, even though each sample has only two values.Does It Make Sense? For Exercises, determine whether the statement makes sense (or is clearly true) or does not make sense (or is clearly false). Explain
Answer Preview: It makes sense because we are not sampling from a Normally Distribu…

, Chapter: 1 -Problem: 15 >> In a study of the XSORT gender selection method developed by the Genetics & IVF Institute, 945 couples given treatment had 66 baby boys and 879 baby girls.
Answer Preview: given that In updated results as of this writing of the XSORT gender selection techn…

, Chapter: 4 -Problem: 1 >> Braking reaction times of 36 randomly selected licensed drivers are measured. Are those data considered quantitative or qualitative? ³ If quantitative, are those values continuous or discrete?
Answer Preview: Braking reaction times of 36 randomly selected licensed drivers are meas…

, Chapter: 1 -Problem: 7 >> A study on the effect of gender on movie attendance was biased because the sample consisted of 800 males and 200 females.
Answer Preview: As per the question No of males 800 No of females 200 It is not given out of 800 males and out …

, Chapter: 2 -Problem: 5 >> A microbiologist measures the distance across a red blood cell and an astronomer measures the distance across the Milky Way galaxy. The absolute error that the microbiologist makes in measuring the cell must be less than the absolute error that the astronomer makes in measuring the Milky Way.Does It Make Sense? For Exercises, determine whether the statement makes sense (or is clearly true) or does
Answer Preview: The bslute errr is the differene between the mesured r inferred …

, Chapter: 2 -Problem: 3 >> A researcher measures the braking reaction time of a subject and records a value of 2.4 seconds, but the subject’s actual braking reaction time is 1.9 seconds. What is the absolute error?
Answer Preview: Records a value of 2 4 s…

, Chapter: 2 -Problem: 6 >> The CPI doubled from 1983 to 2006, so the price of gasoline also doubled over that time period.Does It Make Sense? For Exercises, determine whether the statement makes sense (or is clearly true) or does not make sense (or is clearly false). Explain clearly; not all of these have definitive answers, so your explanation is more important than your chosen answer.
Answer Preview: It does make sense when you say that the CPI doubled from 1983 2006 so the price of gasoline also do…

, Chapter: 2 -Problem: 2 >> Distinguish between absolute and relative difference. Give an example that illustrates how we calculate a relative difference.
Answer Preview: Absolute difference is the 1 absolute value of the differen…

, Chapter: 2 -Problem: 22 >> Using the CPI values from the above table and Table 2.2, determine what a slice of pizza should have cost in 2014 if it cost $1.35 in 1995 and prices had risen with the CPI. What does this tell you about how actual pizza prices changed compared to the CPI? Table 2.2 Transcribed Image Text: TABLE 2.2
Answer Preview: Using the CPI values from the above table and Table 2 2 determine what a slice of pizza should have cost in 2014 if it cost 1 35 in 1995 and prices ha…

, Chapter: 1 -Problem: 13 >> Periodically, some researchers test the hypothesis that cell phones can cause cancer in those who use them. In one such study, it was found that among 420,095 cell phone users, 135 developed cancer of the brain or nervous system.
Answer Preview: No Using mobile phones does not increase the risk of ca…

, Chapter: 1 -Problem: 41 >> You want to conduct a survey of parents of elementary school students in Minneapolis by using telephone calls instead of personal visits. Assume you have directories listing telephone numbers of all (or almost all) parents at each of the city’s elementary schools. What type of sample should you use?
Answer Preview: Suppose we are hired by a politician to determine the amount of support he has among the electo…

, Chapter: 1 -Problem: 2 >> What is a representative sample, and why is it important?
Answer Preview: Representative samples are known for collecting results insights and observations that can be confi…

, Chapter: 4 -Problem: 3 >> What do we mean when we say that distribution is skewed? Briefly describe the basic difference between a distribution that is skewed to the right and a distribution that is skewed to the left.
Answer Preview: What does it mean if the distribution is skewed A distribution is sk…

, Chapter: 1 -Problem: 20 >> Consumer Reports magazine prints a review of new cars and does not accept free products or run any advertisements from any companies.
Answer Preview: CR s No Commercial Use Policy is intended to preserve that indepe…

, Chapter: 4 -Problem: 2 >> What are outliers? Describe the effects of outliers on mean, median, and mode.
Answer Preview: An outlier is essentially a value that is much higher o…

, Chapter: 2 -Problem: 3 >> a. If a typical adult female has a pulse rate that is 6% higher than that of a typical adult male, then the typical adult female’s pulse rate is _____ of the typical adult male’s pulse rate.b. A female has a pulse rate of 80 beats per minute and her brother has a pulse rate that is 95% of hers. What is the brother’s pulse rate?c. If the female in part (b) lowers her pulse rate by 10% through exerc
Answer Preview: Solution a The formula for finding percentage of a number is as follows 6 of 60 beats per minute is …

, Chapter: 1 -Problem: 33 >> Search the Internet for articles and information about the controversy regarding recovering repressed memories. Briefly summarize one or two of the most interesting cases and, based on what you read, express your own opinion as to whether the allegedly recovered memories are being influenced by experimenter effects.
Answer Preview: The allegedly recovered memories …

, Chapter: 1 -Problem: 8 >> In a survey of California residents who text while driving, we obtained a simple random sample by compiling a list of the 24,390,236 licensed drivers in California; then we used a computer to randomly generate 1000 numbers between 1 and 24,390,236, and we selected the drivers that correspond to the generated numbers.
Answer Preview: The main purpose objective of the sampling is to repres…

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, Chapter: 1 -Problem: 5 >> An educational researcher conducted a census to determine the average (mean) number of years it takes undergraduate statistics students to earn a college degree.
Answer Preview: An educational researcher conducted a census to determine the average mean num…

, Chapter: 1 -Problem: 48 >> Find results from a recent poll conducted by a political organization (such as the Republican or Democratic party or an organization that seeks to influence Congress on some particular issue). Briefly describe the sample and how it was chosen. Was the sample chosen in a way that was likely to introduce any bias? Should you be more concerned about bias in such a poll than you would be in a poll con
Answer Preview: Find results from a recent poll conducted by a political organization such as the Republican or Democratic party or an organization that seeks to infl…

, Chapter: 2 -Problem: 2 >> Distinguish between the absolute error and the relative error in a measurement. Give an example in which the absolute error is large but the relative error is small and another example in which the absolute error is small but the relative error is large.
Answer Preview: Distinguish between the absolute error and the relative error in a measurement Give an example in wh…

, Chapter: 1 -Problem: 34 >> Ethical standards change from era to era. One notoriously unethical case was a study of syphilis conducted in Tuskegee, Alabama, from 1932 to 1972. In this study, African American males were told that they were receiving treatment for syphilis, but in fact, they were not. The researchers’ hidden goal was to study the long-term effects of the disease. Use the Internet to learn about the history of
Answer Preview: Over the past decades random controlled trials RCTs have prevailed over clinical judgement case repo…

, Chapter: 2 -Problem: 7 >> Because using the chained CPI would lead to a slower rise in the income thresholds for various tax rates, conservatives often claim that this change would mean a “stealth tax increase.” Similarly, because the change would reduce the annual increases in cost-of-living adjustments, liberals often claim that it would mean a “benefit cut” to Social Security recipients. Do you think either claim is acc
Answer Preview: I think the claim that the chained CPI would result in a stealth tax increase is correct The basic r…

, Chapter: 2 -Problem: 8 >> An announcement in a large department store: “Attention shoppers. Everything in the store is now reduced by10%, but in one hour all prices will be increased by 10%.” The prices will therefore revert to the original amounts.
Answer Preview: Nothing keeps people away more than a stale and outdated store so if youre looking to increase footf…

, Chapter: 2 -Problem: 1 >> Distinguish between absolute and relative change. Give an example that illustrates how we calculate a relative change.
Answer Preview: Absolute change and relative change We can express the cha…

, Chapter: 4 -Problem: 2 >> What is the level of measurement of the values described in Exercise 1 (nominal, ordinal, interval, or ratio)? Exercise 1 Braking reaction times of 36 randomly selected licensed drivers are measured. Are those data considered quantitative or qualitative? ³ If quantitative, are those values continuous or discrete?
Answer Preview: Those data are considered qualitative because they are not quantified values they are self repo…

, Chapter: 1 -Problem: 15 >> If a statistical study is carefully conducted in every possible way, then: (a) Its results must be correct(b) We can have confidence in its results, but it is still possible that the results are not correct(c) We say that the study is perfectly biased.
Answer Preview: Ans is We can have confidence in its results but it is still p…

, Chapter: 4 -Problem: 1 >> Find examples in your own spending or the spending of friends and family members of substitution effects and the purchase of products that were unavailable or of lower quality a few years ago. Overall, do you think these examples support the claim that the CPI overstates the effects of inflation? Defend your opinion.
Answer Preview: Find examples in your own spending or the spending of friends and family members of substitution effects and the purchase of products that were unavai…

, Chapter: 2 -Problem: 3 >> What do we mean by data at the nominal, ordinal, interval, and ratio levels of measurement?
Answer Preview: Ans Levels of measurement also called scales of measurement tell you how precisely variables are recorded In scientific research a variable is anythin…

, Chapter: 1 -Problem: 12 >> Nine-year-old Emily Rosa became an author of an article in the Journal of the American Medical Association after she tested professional touch therapists. Using a cardboard partition, she held her hand above the therapist’s hand, and the therapist was asked to identify the hand that Emily chose.
Answer Preview: A 9 year old girl did a science fair experiment in wh…

, Chapter: 1 -Problem: 11 >> You want to determine the mean age of all statistics students in the United States.
Answer Preview: For the first example the local high school football team probably isn t that huge Even if the schoo…

, Chapter: 2 -Problem: 1 >> In a Wakefield Research survey, 1003 subjects were asked if they ever hesitated to give a handshake because of a fear of germs. Of these respondents, 41.0% answered “yes.”a. What is the number of respondents who answered “yes”?b. If 24 of the respondents said that they were not sure, what is the percentage of “not sure” responses?c. Given that the possible responses are “yes,” “no,” and “not sure,
Answer Preview: Given data Total subjects 1003 and 41 and scoered yes a No of respondents answered yes 41 of 1003 …

, Chapter: 2 -Problem: 1 >> What is an index number? Briefly describe how index numbers are calculated and what they mean.
Answer Preview: Index numbers are a statistician s way of expressing the difference between two measurements by designating one number as the base giving it the value …

, Chapter: 2 -Problem: 33 >> “Categories” 1, 2, 3, 4, and 5, used to describe the intensity of hurricanesLevels of Measurement. For the data described in Exercises, identify the level of measurement (nominal, ordinal, interval, or ratio).
Answer Preview: Since are dealing with categories 1 2 3 4 5 for hurricane and categories ar…

, Chapter: 1 -Problem: 12 >> You want to determine the average (mean) annual salary of the current members of Congress.
Answer Preview: You want to determine the average mean annual salary of the current members o…

, Chapter: 3 -Problem: 28 >> Go to the website for the U.S. Office of Management and Budget (OMB) and look for some of its charts related to the federal budget. Pick two charts of particular interest to you and discuss the data they show.
Answer Preview: The charts most often discussed are the Outlays which includes federal spending on all programs and …

, Chapter: 1 -Problem: 18 >> In a Harris Interactive survey of 1006 randomly selected subjects, 96% of adults said that they wash their hands in public restrooms.
Answer Preview: Sample size 1006 Sample proportion 0 86 The confidence interval …

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, Chapter: 1 -Problem: 17 >> Researchers created a form of genetically modified corn and compared it to nonmodified corn, looking for differences in the substances released into the soil from the corn roots.
Answer Preview: From the field tests across corn growing regions of the United States between 2014 and 2017 th…

, Chapter: 5 -Problem: 8 >> What percentage of adult males have pulse rates greater than 53 bpm?Pulse Rates. In Exercises, assume that pulse rates of adult males are normally distributed with a mean of 70 beats per minute (bpm) and a standard deviation of 11 bpm.
Answer Preview: What percentage of adult males have pulse rates greater than 53 …

, Chapter: 1 -Problem: 4 >> Another potential pitfall comes from the fact that the questionnaires often deal with sensitive issues of personal health, and researchers have no way to confirm that the nurses answer honestly. Do you think that dishonesty could be leading researchers to incorrect conclusions? Defend your opinion.
Answer Preview: Ans Another potential pitfall comes from the fact that the questionnaires often deal with sensitive …

, Chapter: 3 -Problem: 25 >> Find an example in a recent news report of a graph that involves some type of perceptual distortion. Explain the effects of the distortion, and describe how the graph could have been drawn more honestly.
Answer Preview: Misleading graphs are sometimes deliberately misleading and sometimes it s just a case …

, Chapter: 1 -Problem: 21 >> An experiment conducted at Pennsylvania State University was designed to evaluate the effectiveness of irrigation and fertilizers on poplar tree growth. Fertilizer is used with one group of poplar trees in a moist region, and irrigation is used with popular trees in a dry region.
Answer Preview: An experiment conducted at Pennsylvania State University was designed to evaluate the effectiven…

, Chapter: 3 -Problem: 30 >> Create an appropriate display of the navel data collected in Exercise 25 of Section 3.1. Discuss any special properties of this distribution.Exercise 25The navel ratio is defined to be a person’s height divided by the height (from the floor) of his or her navel. An old theory says that, on average, the navel ratio of humans is the golden ratio: (1 + 15)>2. Measure the navel ratio of each person in
Answer Preview: The best way to display the collected navel data is to use a histogram A histogram is a graph that s…

, Chapter: 2 -Problem: 1 >> What is the difference between qualitative data and quantitative data?
Answer Preview: If youre considering a career in dataor in any kind of research field like ps…

, Chapter: 2 -Problem: 29 >> Body temperatures in Fahrenheit of all giraffes in Kenya.Levels of Measurement. For the data described in Exercises, identify the level of measurement (nominal, ordinal, interval, or ratio).
Answer Preview: Correct option C Interval Explanation Temperature in Farenheit is only interval me…

, Chapter: 1 -Problem: 9 >> You want to determine the mean weight of all professional (NFL) football players who were on team rosters during the past season.
Answer Preview: For last year s data The difference between the tallest team Vikings …

, Chapter: 2 -Problem: 29 >> If the population of Montana is 20% less than the population of New Hampshire, then Montana’s population is ____% of New Hampshire’s population.Of versus More Than. Fill in the blanks in Exercises. Briefly explain your reasoning in each case.
Answer Preview: In each example the first sentence asks for a of a number The second sentence asks for that same of …

, Chapter: 1 -Problem: 19 >> A pollster for the U.S. Department of Labor surveys 1500 randomly selected adults about their employment status.
Answer Preview: The major professional organizations of survey researchers have very cle…

, Chapter: 5 -Problem: 8 >> If we record the means from 1000 rolls of 100 dice, the resulting distribution will be closer to a normal distribution than if we record the means from 1000 rolls of 10 dice.Does It Make Sense? For Exercises, determine whether the statement makes sense (or is clearly true) or does not make sense (or is clearly false). Explain clearly; not all of these have definitive answers, so your explanation i
Answer Preview: If we record the means from 1000 rolls of 100 dice the resulting distribution will be closer …

, Chapter: 2 -Problem: 2 >> Total spending on health care in the United States rose from $80 billion in 1973 to $3.0 trillion in 2014. The Consumer Price Index was 44.4 in 1973, and it was 236.7 in 2014 (with 1982–1984 = 100). Compare the change in health care spending from 1973 to 2014 to the overall rate of inflation as measured by the CPI.
Answer Preview: CPI in 1973 44 4 CPI in 2014 236 7 Inflation rate 236 7 44 4 44 4 100 433 1 Increase …

, Chapter: 5 -Problem: 8 >> I found the standard score of the data value, even though I do not know the standard deviation of the data set.Does It Make Sense? For Exercises, determine whether the statement makes sense (or is clearly true) or does not make sense (or is clearly false). Explain clearly; not all of these have definitive answers, so your explanation is more important than your chosen answer.
Answer Preview: The statement makes sense because the standard score …

, Chapter: 1 -Problem: 5 >> I plan to use a double-blind experiment to test the hypothesis that people will experience a decrease in their pulse rate if they exercise vigorously for 40 minutes every day.
Answer Preview: First since the participants do not know which group they are in their beliefs about the treatme…

, Chapter: 2 -Problem: 34 >> Go to the Producer Price Index (PPI) home page. Read the overview and recent news releases. Write a short summary describing the purpose of the PPI and the ways it differs from the CPI. Also summarize any important recent trends in the PPI.Housing Price Index. Realtors use an index to compare housing prices in major cities. The index numbers for several cities are given in the table below. In Exer
Answer Preview: Go to the Producer Price Index PPI home page Read the overview and recent news releases Write a short summary describing the purpose of the PPI and th…

, Chapter: 1 -Problem: 6 >> Do a Web search for news articles that discuss results from the Harvard Nurses’ Health Study or other similar studies. Choose one recent result that interests you, and discuss what it means and how it may affect public health or your own health in the future.
Answer Preview: The latest news article that discusses results from the Harvard Nurses Health Study is that NSAID as…

, Chapter: 3 -Problem: 30 >> Find a graph from a recent news report that, in your opinion, fails in its attempt to display data visually in a meaningful way. Discuss what the graph was trying to show, explain why it failed, and explain how it could have been done better.
Answer Preview: In every aspect of our lives datainformation numbers words or imagesare collected recorded analyzed …

, Chapter: 4 -Problem: 17 >> The heights of 250 randomly selected female statistics students.Describing Distributions. For each distribution described in Exercises, answer the following questions:a. How many modes would you expect for the distribution?b. Would you expect the distribution to be symmetric, left skewed, or right-skewed?
Answer Preview: The distribution for hight of 250 college female student a…

, Chapter: 3 -Problem: 28 >> Explore the energy tables at the U.S. Energy Information Administration (EIA) website. Choose a table that you find interesting and make a graph of its data, using any of the graph types discussed in this section. Explain how you made your graph, and briefly discuss what can be learned from it.
Answer Preview: I chose to graph the data from the table U S Total Electricity Net Generation by Primary Energy Sour…

, Chapter: 4 -Problem: 6 >> A manufacturer uses two different production sites to make batteries for cell phones. There is a defect rate of 2% at one of the sites and a defect rate of 4% at the other site. Therefore, the overall rate of defects must be 3%. It Make Sense? For Exercises, determine whether the statement makes sense (or is clearly true) or does not make sense (or is clearly false). Explain clearly; not all of th
Answer Preview: A manufacturer uses two different production sites to make batteries for cell phones There …

, Chapter: 3 -Problem: 24 >> The website for the World Conservation Monitoring Centre in Great Britain provides data on extinct, endangered, and threatened animal species. Explore these data and summarize some of your more interesting findings with frequency tables.
Answer Preview: The umpqua salamander also known as the Oregon blue spotted salamander or the blue spotted mole salamander formerly from several western states and Br…

, Chapter: 4 -Problem: 7 >> Spud, Inc., a manufacturer of gourmet snacks, employs activity-based costing. The budgeted data for each of the activity cost pools is provided below for the year 2022. Transcribed Image Text: Estimated Estimated Use of Activity Cost Pools Ordering and recefving Food processing Packaging Cost Driver
Answer Preview: Computation of activity rates Activity rates are computed by dividing the estimat…

, Chapter: 3 -Problem: 27 >> Find recent data on international carbon dioxide emissions. Create a graph of the data and discuss any important features or trends that you notice.
Answer Preview: Global CO2 emissions declined by 5 8 in 2020 or almost 2 Gt CO2 the largest ever decline and almost …

, Chapter: 4 -Problem: 3 >> If you are pulled over while driving and given a breathalyzer test for alcohol, what is the result called if the test incorrectly indicates that you have consumed alcohol?
Answer Preview: The result is called a false positive test False positives occur when a biological system wrongly id…

, Chapter: 4 -Problem: 18 >> The heights of 500 female students, half of whom are college students while the other half are second-grade students.Describing Distributions. For each distribution described in Exercises, answer the following questions:a. How many modes would you expect for the distribution?b. Would you expect the distribution to be symmetric, left skewed, or right-skewed?
Answer Preview: Heights The heights of 500 female students half of whom are college studen…

, Chapter: 3 -Problem: 22 >> Refer to the Dvorak data in Exercise 21 in Section 3.1 and construct a dotplot. Compare the result to the dotplot from Exercise 21 above. Based on the results, does either keyboard configuration appear to be better? Explain. Exercise 21The traditional keyboard configuration is called a Qwerty keyboard because of the positioning of the letters QWERTY on the left in the top row of letters. Developed
Answer Preview: The dot plot for the Q wer ty keyboard ratings looks like this 0 1 2 The dot plot for the D vor …

, Chapter: 4 -Problem: 33