Question: A random sample is selected from a

> What percentage of the time will a variable that has a t distribution with the specified degrees of freedom fall in the indicated region? a. 5 df, between -2.02 and 2.02 b. 14 df, between -2.98 and 2.98 c. 22 df, outside the interval from -1.72 to 1.7

> Because of safety considerations, in May 2003, the Federal Aviation Administration (FAA) changed its guidelines for how small commuter airlines must estimate passenger weights. Under the old rule, airlines used 180 pounds as a typical passenger weight (i

> A manufacturer of college textbooks is interested in estimating the strength of the bindings produced by a particular binding machine. Strength can be measured by recording the force required to pull the pages of a book from its binding. If this force is

> Acrylic bone cement is sometimes used in hip and knee replacements to secure an artificial joint in place. The force required to break an acrylic bone cement bond was measured for six specimens, and the resulting mean and standard deviation were 306.09 N

> USA TODAY reported that the average amount of money spent on coffee drinks each month is $78.00 (USA Snapshot, November 4, 2016). a. Suppose that this estimate was based on a representative sample of 20 adult Americans. Would you recommend using the one

> Samples of two different models of cars were selected, and the actual speed for each car was determined when the speedometer registered 50 mph. The resulting 95% confidence intervals for mean actual speed were (51.3, 52.7) for model 1 and (49.4, 50.6) fo

> The formula used to calculate a confidence interval for the mean of a normal population is What is the appropriate t critical value for each of the following confidence levels and sample sizes? a. 90% confidence, n = 12 b. 90% confidence, n = 25 c. 95

> What percentage of the time will a variable that has a t distribution with the specified degrees of freedom fall in the indicated region? a. 10 df, between -2.23 and 2.23 b. 24 df, between -2.80 and 2.80 c. 24 df, to the right of 2.80

> The authors of the paper “Beyond the Shooter Game: Examining Presence and Hostile Outcomes among Male Game Players” (Communication Research [2006]: 448–466) studied how video game content might influe

> The paper referenced in Exercise 16.3 described an experiment to determine if restrictive age labeling on video games increased the attractiveness of the game for boys ages 12 to 13. In that exercise, the null hypothesis was H0: µ1 = Â

> Can use of an online plagiarism-detection system reduce plagiarism in student research papers? The paper “Plagiarism and Technology: A Tool for Coping with Plagiarism” ( Journal of Education for Business [2005]: 149&ac

> The paper “women’s and men’s eating behavior Following exposure to ideal-body images and text” (Communication Research [2006]: 507–529) describes an experiment in w

> Consider the accompanying data on plant growth after the application of five different types of growth hormone. a. C arry out the ANOVA F test using a significance level of  = 0.05. b. What happens when the T-K procedure is applied?

> In an experiment to investigate the effect of the portrayal of female characters in superhero movies, researchers randomly assigned female college students to one of three groups (“the empowering (super) heroine? the effects of sexualiz

> Suppose that samples of six different brands of diet or imitation margarine were analyzed to determine the level of physiologically active polyunsaturated fatty acids (PAPUFA, in percent), resulting in the accompanying data. a. Carry out a test to dete

> Do lizards play a role in spreading plant seeds? Some research carried out in South Africa would suggest so (“Dispersal of namaqua Fig [Ficus cordata cordata] seeds by the augrabies Flat lizard [Platysaurus broadleyi],â€&#157

> The paper referenced in the Exercise 16.15 also gave the following underscoring pattern for men. a. Write a few sentences interpreting this underscoring pattern. b. Using your answers from Part (a) and from the Exercise 16.15, write a few sentences de

> The paper “trends in blood lead levels and blood lead testing among U.s. children aged 1 to 5 Years” (Pediatrics [2009]: e376–e385) gave data on blood lead levels (in mg/dL) for samples of children li

> The following data resulted from a flammability study in which specimens of five different fabrics were tested to determine burn times (in seconds). The accompanying output gives the T-K intervals as calculated by Minitab. Identify significant differen

> The accompanying underscoring pattern appears in the article “women’s and men’s eating behavior Following exposure to ideal-body images and text” (Communications Research [2006]: 507

> Leaf surface area is an important variable in plant gas-exchange rates. Dry matter per unit surface area (mg/ cm3) was measured for trees raised under three different growing conditions. Let m1, m2, and m3 represent the mean dry matter per unit surface a

> Parents are frequently concerned when their child seems slow to begin walking (although when the child finally walks, the resulting havoc sometimes has the parents wishing they could turn back the clock!). The article “walking in the ne

> It is common for baseball pitchers to use stretching to prepare for a game. But does this make a difference? The authors of the paper “the acute effects of Upper extremity stretching on throwing velocity in baseball throwersâ&#128

> The chapter Preview Example described a study comparing three groups of college students (soccer athletes, nonsoccer athletes, and a comparison group consisting of students who did not participate in intercollegiate sports). The following is information

> The accompanying summary statistics for a measure of social marginality for samples of youths, young adults, adults, and seniors appeared in the paper “Perceived causes of loneliness in adulthood” (Journal of Social Be

> Do people feel hungrier after sampling a healthy food? The authors of the paper “when healthy Food makes You hungry” (Journal of Consumer Research [2010]: s34–s44) carried out a study to answer this q

> In an experiment to investigate the performance of four different brands of spark plugs intended for use on a 125-cc motorcycle, five plugs of each brand were tested, and the number of miles (at a constant speed) until failure was observed. A partially c

> The experiment described in Example 16.4 also gave data on change in body fat mass for men (“growth hormone and sex steroid administration in healthy aged women and men,” Journal of the American Medical Association [20

> The paper referenced in Exercise 16.3 also gave data for 12- to 13-year-old girls. Data consistent with summary values in the paper are shown below. Do the data provide convincing evidence that the mean rating associated with the game description for 12-

> Give as much information as you can about the P-value of the single-factor ANOVA F test in each of the following situations. a. k = 5, n1 = n2 = n3 = n4 = n5 = 4, F = 5.37 b. k = 5, n1 = n2 = n3 = 5, n4 = n5 = 4, F = 2.83 c. k = 3, n1 = 4, n2 = 5, n3

> The authors of the paper “Reading Subtitles and Taking Enotes While Learning Scientific Materials in a Multimedia Environment” (Educational Technology and Society [2016): 47–58) were interested in det

> The authors of the paper “Age and Violent Content Labels Make Video Games Forbidden Fruits for Youth” (Pediatrics [2009]: 870–876) carried out an experiment to determine if restrictive labels on video

> Employees of a certain state university system can choose from among four different health plans. Each plan differs somewhat from the others in terms of hospitalization coverage. Four random samples of recently hospitalized individuals were selected, eac

> Give as much information as you can about the P-value for an upper-tailed F test in each of the following situations. a. df1 = 4, df2 = 15, F = 5.37 b. df1 = 4, df2 = 15, F = 1.90 c. df1 = 4, df2 = 15, F = 4.89 d. df1 = 3, df2 = 20, F = 14.48 e. df1

> The paper “patterns and composition of weight change in college freshmen” (College Student Journal [2015]: 553–564) reported that the freshman year weight gain for the students in a representative sample of 103 freshmen at a midwestern university was 5.7

> The Bureau of Alcohol, Tobacco, and Firearms (ATF) has been concerned about lead levels in California wines. In a previous testing of wine specimens, lead levels ranging from 50 to 700 parts per billion were recorded. How many wine specimens should be te

> The paper referenced in the previous exercise also reported that for a representative sample of 68 second-year students at the university, the sample mean procrastination score was 41.00 and the sample standard deviation was 6.82. a. Construct a 95% con

> Students in a representative sample of 65 first-year students selected from a large university in England participated in a study of academic procrastination (“Study goals and procrastination tendencies at Different Stages of the Undergraduate Degree,” S

> The paper “the effects of adolescent Volunteer activities on the perception of Local Society and community Spirit mediated by Self-conception” (Advanced Science and Technology Letters [2016]: 19–23) describes a survey of a large representative sample of

> The two intervals (114.4, 115.6) and (114.1, 115.9) are confidence intervals for µ = mean resonance frequency (in hertz) for all tennis rackets of a certain type. The two intervals were calculated using the same sample data. a. What is the value of the

> The formula used to calculate a confidence interval for the mean of a normal population is What is the appropriate t critical value for each of the following confidence levels and sample sizes? a. 95% confidence, n = 17 b. 99% confidence, n = 24 c. 90

> What percentage of the time will a variable that has a t distribution with the specified degrees of freedom fall in the indicated region? (Hint: See discussion on page 581.) a. 10 df, between -1.81 and 1.81 b. 24 df, between -2.06 and 2.06 c. 24 df,

> An airplane with room for 100 passengers has a total baggage limit of 6000 pounds. Suppose that the weight of baggage checked by an individual passenger, x, has a mean of 50 pounds and a standard deviation of 20 pounds. If 100 passengers will board a fli

> A manufacturing process is designed to produce bolts with a diameter of 0.5 inches. Once each day, a random sample of 36 bolts is selected and the bolt diameters are recorded. If the resulting sample mean is less than 0.49 inches or greater than 0.51 inc

> Suppose that a random sample of size 100 is to be drawn from a population with standard deviation 10. a. What is the probability that the sample mean will be within 20 of the value of m? b. F or this example (n = 100, σ = 10), complete each of the foll

> Suppose that the population mean value of interpupillary distance (the distance between the pupils of the left and right eyes) for adult males is 65 mm and that the population standard deviation is 5 mm. a. If the distribution of interpupillary distance

> A sign in the elevator of a college library indicates a limit of 16 persons. In addition, there is a weight limit of 2500 pounds. Assume that the average weight of students, faculty, and staff at this college is 150 pounds, that the standard deviation is

> Explain the difference between x and µ x.

> For which of the sample sizes given in the previous exercise would it be reasonable to think that the sampling distribution of x is approximately normal in shape?

> Suppose that a random sample of size 64 is to be selected from a population with mean 40 and standard deviation 5. a. What are the mean and standard deviation of the sampling distribution of x? Describe the shape of the sampling distribution of x? b. Wh

> Explain the difference between σ and σx.

> The paper “alcohol consumption, Sleep, and academic performance among college Students” (Journal of Studies on Alcohol and Drugs [2009]: 355–363) describes a study of n = 236 students that were random

> For which of the sample sizes given in the previous exercise would it be reasonable to think that the x sampling distribution is approximately normal in shape?

> A random sample is selected from a population with mean µ = 60 and standard deviation σ = 3. Determine the mean and standard deviation of the sampling distribution of x for each of the following sample sizes: a. n = 6 b. n = 18 c. n = 42 d. n = 75 e

> The time that people have to wait for an elevator in an office building has a uniform distribution over the interval from 0 to 1 minute. For this distribution, µ = 0.5 and σ = 0.289. a. If x is the average waiting time for a random sample of n = 16 wait

> Explain the difference between µ and µx.

> The paper “alcohol consumption, Sleep, and academic performance among college Students” ( Journal of Studies on Alcohol and Drugs [2009]: 355–363) describes a study of n = 236 students who were random

> For which of the sample sizes given in the previous exercise would it be reasonable to think that the x sampling distribution is approximately normal in shape?

> A random sample is selected from a population with mean µ = 100 and standard deviation σ = 10. Determine the mean and standard deviation of the sampling distribution of x for each of the following sample sizes: a. n = 9 b. n = 15 c. n = 36 d. n = 50

> The press release titled “Nap Time” (July 2009, pewresearch. org, retrieved May 27, 2017) described results from a nationally representative survey of 1488 adult Americans. The survey asked several demographic question

> The paper referenced in the previous exercise also included the accompanying data on how often students said they had consumed fried potatoes (French fries or potato chips) in the past week. Use the accompanying Minitab output to carry out a chi-square

> The following passage is from the paper “Gender Differences in Food Selections of Students at a Historically Black College and University” (College Student Journal [2009]: 800–806): Also significant was the proportion of males and their water consumption

> The report “Consumer Revolving Credit and Debt Over the Life Cycle and Business Cycle” describes a study conducted by the Federal Reserve Bank of Boston (www.bostonfed. org, October 2015, retrieved May 27, 2017). Data

> The report “Education Pays 2016” (The College Board, trends.collegeboard.org/sites/default/files/education-pays -2016-full-report.pdf, retrieved May 27, 2017) provided information on education level and earnings for a

> The authors of the paper “Movie Character Smoking and Adolescent Smoking: Who Matters More, Good Guys or Bad Guys?” (Pediatrics [2009]: 135–141) studied characters who were depicted smoking in movies

> The accompanying data on degree of spirituality for a random sample of natural scientists and a random sample of social scientists working at research universities appeared in the paper “Conflict Between Religion and Science Among Acade

> In a study of high-achieving high school graduates, the authors of the report “High-Achieving Seniors and the College Decision” (Lipman Hearne, October 2009) surveyed 828 high school graduates who were considered &acir

> The report referenced in the previous two exercises also classified 817 fatal bicycle accidents according to the month in which the accidents occurred, resulting in the accompanying table. a. To determine if some months are riskier than others, use the

> Suppose a safety officer proposes that bicycle fatalities are twice as likely to occur between noon and midnight as during midnight to noon and suggests the following hypothesis: /where p1 is the proportion of accidents occurring between midnight and noo

> The report “Fatality Facts 2004: Bicyclists 2015” (Insurance Institute, 2015, www.iihs.org/iihs/topics/t/pedestrians-and-bicyclists/fatalityfacts/bicycles, retrieved May 27, 2017) included the following table classifyi

> The authors of the paper “Racial Stereotypes in Children’s Television Commercials” ( Journal of Advertising Research [2008]: 80–93) counted the number of times that characters of dif

> Jail inmates can be classified into one of the following four categories according to the type of crime committed: violent crime, crime against property, drug crime, and public-order offenses. Suppose that random samples of 500 male inmates and 500 femal

> The authors of the paper “Risk of Malnutrition Is an Independent Predictor of Mortality, Length of Hospital Stay, and Hospitalization Costs in Stroke Patients” (Journal of Stroke and Cerebrovascular Diseases [2016]: 79

> The report referenced in the previous exercise also provided data on perception of money management skills by age group. Use the data from 788 people in the accompanying table to determine if there is evidence of an association between age and perception

> The report “Majoring in Money: How American College Students Manage Their Finances” (June 28, 2016, salliemae.newshq.businesswire.com/sites/salliemae.newshq.businesswire .com/files/doc_library/file/SallieMae_Majoringin

> Does viewing angle affect a person’s ability to tell the difference between a female nose and a male nose? This important (?) research question was examined in the article “You Can Tell by the Nose: Judging Sex from an

> Each person in a representative sample of 445 college students age 18 to 24 was classified according to age and to the response to the following question: “How often have you used a credit card to buy items knowing you wouldnâ&#12

> The report “Smartphone Ownership and Internet Usage Continues to Climb in Emerging Economies” (Pew Research Center, February 22, 2016, www.pewglobal .org/2016/02/22/smartphone-ownership-and-internet -usage-continues-to

> Are babies born to mothers who use assistive reproduction technology (ART) more likely to be born prematurely than babies conceived naturally? The data in the accompanying table are from the paper “Child Growth from Birth to 18 Months A

> Explain the difference between situations that would lead to a chi-square test for homogeneity and those that would lead to a chi-square test for independence.

> Explain the difference between situations that would lead to a chi-square goodness-of-fit test and those that would lead to a chi-square test of homogeneity.

> Give an example of a situation where it would be appropriate to use a chi-square test of independence. Describe the population that would be sampled and the two variables that would be recorded.

> Give an example of a situation where it would be appropriate to use a chi-square test of homogeneity. Describe the populations that would be sampled and the variable that would be recorded.

> Each person in a large sample of German adolescents was asked to indicate which of 50 popular movies he or she had seen in the past year. Based on the response, the amount of time (in minutes) of alcohol use contained in the movies the person had watched

> The paper “Contemporary College Students and Body Piercing” (Journal of Adolescent Health [2004]: 58–61) described a survey of 490 undergraduate students at a state university in the southwestern regi

> The Knight Foundation investigated whether high school students agreed with the statement that people should be allowed to burn or deface the American flag as a political statement. This question was asked in a survey of a representative sample of high s

> The data in the accompanying table are from the paper “Gender Differences in Food Selections of Students at a Historically Black College and University” (College Student Journal [2009]: 800–806). Supp

> The paper “Credit Card Misuse, Money Attitudes, and Compulsive Buying Behavior: Comparison of Internal and External Locus of Control Consumers” (College Student Journal [2009]: 268–275) describes a su

> The authors of the paper “The Relationship of Field of Study to Current Smoking Status Among College Students” (College Student Journal [2009]: 744–754) carried out a study to investigate if smoking r

> The Knight Foundation asked each person in a representative sample of high school students and in a representative sample of high school teachers which of the rights guaranteed by the First Amendment they thought was the most important (â€&#15

> Some colleges now allow students to pay their tuition using a credit card. The report “Credit Card Tuition Payment Survey 2014” (www.creditcards.com/credit-card -news/tuition-charge-fee-survey.php, retrieved May 27, 20

> The authors of the paper “External Factors and the Incidence of Severe Trauma: Time, Date, Season and Moon” (Injury [2014]: S93–S99) classified admissions to hospitals in Germany according to season.

> Birds use color to select and avoid certain types of food. The authors of the article “Colour Avoidance in Northern Bobwhites: Effects of Age, Sex, and Previous Experience” (Animal Behaviour [1995]: 519â€&#1

> Suppose that each observation in a random sample of 100 fatal bicycle accidents in 2015 was classified according to the day of the week on which the accident occurred. Data consistent with information on the Insurance Institute for Highway Safety website

> The article “Linkage Studies of the Tomato” (Transactions of the Royal Canadian Institute [1931]: 1–19) reported the accompanying data on phenotypes resulting from crossing tall cut-leaf tomatoes with

> A certain genetic characteristic of a particular plant can appear in one of three forms (phenotypes). A researcher has developed a theory, according to which the hypothesized proportions are p1 = 0.25, p2 = 0.50, and p3 = 0.25. A random sample of 200 pla

> Think about how you would answer the following question. Next Wednesday’s meeting has been moved forward two days. What day is the meeting now that it has been rescheduled? This question is ambiguous, as “moved forwa

> For which of the X 2 and df pairs in the previous exercise would the null hypothesis be rejected if a significance level of  = 0.01 were used?

> What is the approximate P-value for the following values of X 2 and df? a. X 2 = 34.52, df = 13 b. X 2 = 39.25, df = 16 c. X 2 = 26.00, df = 19

> A popular urban legend is that more babies than usual are born during certain phases of the lunar cycle, especially near the full moon. The paper “The Effect of the Gravitation of the Moon on Frequency of Births” (Envi