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Statistics Plus New Mylab Statistics With Pearson Etext Access Card Package 13th Edition James Mcclave ,Terry Sincich - Solutions
Music performance anxiety. Refer to the British Journal of Music Education (Mar. 2014) study of performance anxiety by music students, Exercise 2.39(p. 78). Recall that the Performance Anxiety Inventory (PAI) was used to measure music performance anxiety on a scale from 20 to 80 points. The table
Giraffes have excellent vision. Due to habitat, giraffes travel in small groups. Hence, they require excellent vision in order to detect predators. The eyesight of giraffes was studied in African Zoology (Oct. 2013). The researchers measured a variety of eye characteristics for 27 giraffes native
Radon exposure in Egyptian tombs. Many ancient Egyptian tombs were cut from limestone rock that contained uranium. Since most tombs are not well- ventilated, guards, tour guides, and visitors may be exposed to deadly radon gas. In Radiation Protection Dosimetry (Dec. 2010), a study of radon
Rainfall and desert ants. Refer to the Journal of Biogeography (Dec. 2003) study of ants and their habitat in the desert of Central Asia, presented in Exercise 2.68(p. 91). Recall that botanists randomly selected five sites in the Dry Steppe region and six sites in the Gobi Desert where ants were
Lobster trap placement. An observational study of teams fishing for the red spiny lobster in Baja California Sur, Mexico, was conducted and the results published in Bulletin of Marine Science (Apr. 2010). One of the variables of interest was the average distance separating traps—called trap
Shell lengths of sea turtles. Refer to the Aquatic Biology(Vol. 9, 2010) study of green sea turtles inhabiting the Grand Cayman South Sound lagoon, Exercise 7.24(p. 354). Time-depth recorders were deployed on 6 of the 76 captured turtles. The time-depth recorders allowed the environmentalists to
Duration of daylight in western Pennsylvania. What area of the United States has the least amount of daylight, on average?Having grown up in western Pennsylvania, co-author Sincich wonders if it is his hometown of Sharon, PA. Data on the number of minutes of daylight per day in Sharon, PA, for 12
Do social robots walk or roll? Refer to the International Conference on Social Robotics (Vol. 6414, 2010) study on the current trend in the design of social robots, Exercise 2.7(p. 66). Recall that in a random sample of social robots obtained through a Web search, 28 were built with wheels.The
Pitch memory of amusiacs. A team of psychologists and neuroscientists tested the pitch memory of individuals diagnosed with amusia (a disorder that impacts one’s perception of music) and reported their results in Advances in Cognitive Psychology (Vol. 6, 2010). Each in a sample of 17 amusiacs
Shaft graves in ancient Greece. Refer to the American Journal of Archaeology (Jan. 2014) study of shaft graves in ancient Greece, Exercise 2.37(p. 78). Recall that shaft graves are named for the beautifully decorated sword shafts that are buried along with the bodies. The table on p. 364 gives the
Oxygen bubbles in molten salt. Molten salt is used in an electro-refiner to treat nuclear fuel waste. Eventually, the salt needs to be purified (for reuse) or disposed of.A promising method of purification involves oxidation.Such a method was investigated in Chemical Engineering Research and Design
Minimizing tractor skidding distance. In planning for a new forest road to be used for tree harvesting, planners must select the location that will minimize tractor skidding distance. In the Journal of Forest Engineering (July 1999), researchers wanted to estimate the true mean skidding distance
Reproduction of bacteria-infected spider mites. Zoologists in Japan investigated the reproductive traits of spider mites with a bacterial infection (Heredity, Jan. 2007). Male and female pairs of infected spider mites were mated in a laboratory and the number of eggs produced by each female
Antigens for a parasitic roundworm in birds. Ascaridia galli is a parasitic roundworm that attacks the intestines of birds, especially chickens and turkeys. Scientists are working on a synthetic vaccine (antigen) for the parasite. The success of the vaccine hinges on the characteristics of DNA in
Study on waking sleepers early. Scientists have discovered increased levels of the hormone adrenocorticotropin in people just before they awake from sleeping (Nature, Jan. 7, 1999). In the study described, 15 subjects were monitored during their sleep after being told that they would be woken at a
Describe the sampling distribution of pn on the basis of large samples of size n. That is, give the mean, the standard deviation, and the (approximate) shape of the distribution of pn when large samples of size n are (repeatedly)selected from the binomial distribution with probability p of success.
Explain the meaning of the phrase “pn is an unbiased estimator of p.”
A random sample of size n = 250 yielded p = .80.a. Is the sample size large enough to use the large sample approximation to construct a confidence interval for p?Explain.b. Construct a 95% confidence interval for p.c. Interpret the 95% confidence interval.d. Explain what is meant by the phrase
A random sample of size n = 169 yielded pn = .65.a. Is the sample size large enough to use the methods of this section to construct a confidence interval for p?Explain.b. Construct a 90% confidence interval for p.c. What assumption is necessary to ensure the validity of this confidence interval?
For the binomial sample information summarized in each part, indicate whether the sample size is large enough to use the methods of this chapter to construct a confidence interval for p.a. n = 500, pn = .05b. n = 100, pn = .05c. n = 10, pn = .5d. n = 10, pn = .3
A random sample of 50 consumers taste-tested a new snack food. Their responses were coded (0: do not like; 1:like; 2: indifferent) and recorded as follows:a. Use an 80% confidence interval to estimate the proportion of consumers who like the snack food.b. Provide a statistical interpretation for
Paying for music downloads. If you use the Internet, have you ever paid to access or download music? This was one of the questions of interest in a recent Pew Internet and American Life Project Survey (Oct. 2010). Telephone interviews were conducted on a representative sample of 1,003 adults living
Interactions in a children’s museum. Refer to the Early Childhood Education Journal (Mar. 2014) study of interactions in a children’s museum, Exercise 2.19(p. 69).(Interactions by visitors to the museum included showand-tell, learning, teaching, refocusing, participatory play, advocating, and
Is Starbucks coffee overpriced? The Minneapolis Star Tribune (Aug. 12, 2008) reported that 73% of Americans say that Starbucks coffee is overpriced. The source of this information was a national telephone survey of 1,000 American adults conducted by Rasmussen Reports.a. Identify the population of
Nannies who work for celebrities. The International Nanny Association reports that in a sample of 528 in-home child care providers (nannies), 20 work for either a nationally known, a locally known, or an internationally known celebrity(2011 International Nanny Association Salary and Benefits
National Firearms Survey. Refer to the Harvard School of Public Health survey to determine the size and composition of privately held firearm stock in the United States, presented in Exercise 3.85(p. 183). Recall that, in a representative household telephone survey of 2,770 adults, 26% reported
Are you really being served red snapper? Refer to the Nature (July 15, 2004) study of fish specimens labeled“red snapper,” presented in Exercise 3.93(p. 185). Recall that federal law prohibits restaurants from serving a cheaper look-alike variety of fish to customers who order red snapper. In
What we do when we are sick at home. USA Today (Feb. 15, 2007) reported on the results of an opinion poll in which adults were asked what one thing they are most likely to do when they are home sick with a cold or the flu. In the survey, 63% said that they are most likely to sleep and 18%said that
Curbing street gang gun violence. Refer to the Journal of Quantitative Criminology (Mar. 2014) study of a program designed to curb street gang gun violence, Exercise 2.18(p. 69).After implementation of Boston’s Operation Ceasefire program, the researchers examined 80 shootings by members of a
Do social robots walk or roll? Refer to the International Conference on Social Robotics (Vol. 6414, 2010) study of the trend in the design of social robots, Exercise 2.7(p. 66). The researchers obtained a random sample of 106 social robots through a Web search and determined that 63 were designed
Study of aircraft bird strikes. As worldwide air traffic volume has grown over the years, the problem of airplanes striking birds and other flying wildlife has increased dramatically. The International Journal for Traffic and Transport Engineering (Vol. 3, 2013) reported on a study of aircraft bird
Teenagers’ use of emoticons in school writing. Due to the popularity of instant messaging and social networking, informal elements such as emoticons (e.g., the symbol “:)”to represent a smile) and abbreviations (e.g., “LOL” for“laughing out loud”) have worked their way into
Characteristics of ice-melt ponds. Refer to the University of Colorado study of ice-melt ponds in the Canadian Arctic, presented in Exercise 2.15(p. 68). Environmental engineers are using data collected by the National Snow and Ice Data Center to learn how climate affects the sea ice. Data on 504
Splinting in mountain-climbing accidents. The most common injury that occurs among mountain climbers is trauma to the lower extremity (leg). Consequently, rescuers must be proficient in immobilizing and splinting of fractures.In High Altitude Medicine & Biology (Vol. 10, 2009), researchers provided
Eye shadow, mascara, and nickel allergies. Pigmented makeup products like mascara and eye shadow may contain metal (e.g., nickel) allergens. Is a nickel allergy more likely to occur in women who report cosmetic dermatitis from using eye shadow or mascara? This was the question of interest in a
How does the sampling error SE compare with the width of a confidence interval?
True or false. For a specified sampling error SE, increasing the confidence level 11 - a2 will lead to a larger n in determining the sample size.
True or false. For a fixed confidence level 11 - a2, increasing the sampling error SE will lead to a smaller n in determining the sample size.
If you wish to estimate a population mean with a sampling distribution error SE = .29 using a 95% confidence interval and you know from prior sampling that s2 is approximately equal to 3.8, how many observations would have to be included in your sample?
Suppose you wish to estimate a population mean correct to within .12 with a confidence level of .90. You do not know s2, but you know that the observations will range in value between 36 and 44.a. Find the approximate sample size that will produce the desired accuracy of the estimate. You wish to
In each case, find the approximate sample size required to construct a 99% confidence interval for p that has sampling error SE = .07.a. Assume that p is near .4.b. Assume that you have no prior knowledge about p, but you wish to be certain that your sample is large enough to achieve the specified
A 90% confidence interval for p is given as (.48, .72). How large was the sample used to construct this interval?
Suppose you wish to estimate the mean of a normal population with a 95% confidence interval and you know from prior information that s2 ≈ 1.a. To see the effect of the sample size on the width of the confidence interval, calculate the width of the confidence interval for n = 36, 64, 81, 225, and
Giraffes have excellent vision. Refer to the African Zoology(Oct. 2013) study of a giraffe’s eyesight, Exercise 7.38(p. 362). Recall that the researchers measured the eye mass for a sample of 27 giraffes native to Zimbabwe, Africa, and found x = 53.4 grams and s = 8.6 grams. Suppose the objective
Shaft graves in ancient Greece. Refer to the American Journal of Archaeology (Jan. 2014) study of shaft graves in ancient Greece, Exercise 7.46(p. 363). Recall that you estimated m, the average number of shafts buried in ancient Greece graves, using data collected for 13 recently discovered grave
Risk of home burglary in cul-de-sacs. Research published in the Journal of Quantitative Criminology (Mar. 2010) revealed that the risk of burglaries in homes located on culde-sacs is lower than for homes on major roads. Suppose you want to estimate the true percentage of cul-de-sac homes in your
Lobster trap placement. Refer to the Bulletin of Marine Science (Apr. 2010) study of lobster trap placement, Exercise 7.41(p. 363). Recall that you used a 95% confidence interval to estimate the mean trap spacing (in meters)for the population of red spiny lobster fishermen fishing in Baja
Aluminum cans contaminated by fire. A gigantic warehouse located in Tampa, Florida, stores approximately 60 million empty aluminum beer and soda cans.Recently, a fire occurred at the warehouse. The smoke from the fire contaminated many of the cans with blackspot, rendering them unusable. A
Do social robots walk or roll? Refer to the International Conference on Social Robotics (Vol. 6414, 2010) study of the trend in the design of social robots, Exercise 7.67(p. 371).Recall that you used a 99% confidence interval to estimate the proportion of all social robots designed with legs but no
Duration of daylight in western Pennsylvania. Refer to the Naval Oceanography Portal data on number of minutes of daylight per day in Sharon, PA, Exercise 7.43(p. 363). An estimate of the mean number of minutes of daylight per day was obtained using data collected for 12 randomly selected days (one
Pitch memory of amusiacs. Refer to the Advances in Cognitive Psychology (Vol. 6, 2010) study of pitch memory of amusiacs, Exercise 7.45(p. 363). Recall that diagnosed amusiacs listened to a series of tone pairs and were asked to determine if the tones were the same or different.In the first trial,
Shopping on Black Friday. Refer to the International Journal of Retail and Distribution Management (Vol. 39, 2011) survey of Black Friday shoppers, Exercise 7.22(p. 353). One question was “How many hours do you usually spend shopping on Black Friday?”a. How many Black Friday shoppers should be
Study of aircraft bird strikes. Refer to the International Journal for Traffic and Transport Engineering (Vol. 3, 2013) study of aircraft bird strikes at a Nigerian airport, Exercise 7.68(p. 371). Recall that an air traffic controller wants to estimate the true percentage of aircraft bird strikes
Bacteria in bottled water. Is the bottled water you drink safe? The Natural Resources Defense Council warns that the bottled water you are drinking may contain more bacteria and other potentially carcinogenic chemicals than are allowed by state and federal regulations. Of the more than 1,000
Do you think you smell? Refer to the Depression and Anxiety (June 2010) study of patients who suffer from olfactory reference syndrome (ORS), Exercise 7.72(p. 372). Recall that psychiatrists disagree over how prevalent ORS is in the human population. Suppose you want to estimate the true proportion
Caffeine content of coffee. According to a Food and Drug Administration (FDA) study, a cup of coffee contains an average of 115 milligrams (mg) of caffeine, with the amount per cup ranging from 60 to 180 mg. Suppose you want to repeat the FDA experiment in order to obtain an estimate of the mean
Eye shadow, mascara, and nickel allergies. Refer to the Journal of the European Academy of Dermatology and Venereology (June 2010) study of the link between nickel allergies and use of mascara or eye shadow, Exercise 7.73(p. 372). Recall that two groups of women were sampled:one group with cosmetic
Preventing production of defective items. It costs more to produce defective items—since they must be scrapped or reworked—than it does to produce non-defective items.This simple fact suggests that manufacturers should ensure the quality of their products by perfecting their production
What sampling distribution is used to find an interval estimate for s2?
What conditions are required for a valid confidence interval for s2?
How many degrees of freedom are associated with a chisquare sampling distribution for a sample of size n?
For the combinations of a and degrees of freedom (df) in parts a through d below, use either Table IV in Appendix B or statistical software to find the values of x2 a>2 and x21 1 - a>22 that would be used to form a confidence interval for s2.a. a = .05, df = 6b. a = .10, df = 14c. a = .01, df =
Given the following values of x, s, and n, form a 90% confidence interval for s2.a. x = 21, s = 2.7, n = 50b. x = 1.7, s = .04, n = 14c. x = 160, s = 31.7, n = 24d. x = 9.8, s = 1.6, n = 5
Refer to Exercise 7.103. For each part, a–d, form a 90%confidence interval for s.
A random sample of n = 6 observations from a normal distribution resulted in the data shown in the table.Compute a 95% confidence interval for s2. 8 2 3 7 11 6
Corporate sustainability of CPA firms. Refer to the Business and Society (Mar. 2011) study on the sustainability behaviors of CPA corporations, Exercise 7.18(p. 352). Recall that the level of support for corporate sustainability (measured on a quantitative scale ranging from 0 to 160 points) was
Characteristics of a rockfall. Refer to the Environmental Geology (Vol. 58, 2009) simulation study of how far a block from a collapsing rock wall will bounce down a soil slope, Exercise 2.61(p. 89). Rebound lengths (in meters)were estimated for 13 rock bounces. The data are repeated in the table. A
Motivation of drug dealers. Refer to the Applied Psychology in Criminal Justice (Sept. 2009) study of the personality characteristics of convicted drug dealers, Exercise 7.17(p. 352). A random sample of 100 drug dealers had a mean Wanting Recognition (WR) score of 39 points, with a standard
Facial structure of CEOs. Refer to the Psychological Science (Vol. 22, 2011) study of a chief executive officer’s facial structure, Exercise 7.21(p. 353). Recall that the facial width-to-height ratio (WHR) was determined by computer analysis for each in a sample of 55 CEOs at publicly traded
Antigens for a parasitic roundworm in birds. Refer to the Gene Therapy and Molecular Biology (June 2009) study of DNA in peptide (protein) produced by antigens for a parasitic roundworm in birds, Exercise 7.50(p. 364).Recall that scientists tested each in a sample of 4 alleles of antigen-produced
Oil content of fried sweet potato chips. The characteristics of sweet potato chips fried at different temperatures were investigated in the Journal of Food Engineering (Sept.2013). A sample of 6 sweet potato slices were fried at 130°using a vacuum fryer. One characteristic of interest to the
Radon exposure in Egyptian tombs. Refer to the Radiation Protection Dosimetry (Dec. 2010) study of radon exposure in tombs carved from limestone in the Egyptian Valley of Kings, Exercise 7.39(p. 362). The radon levels in the inner chambers of a sample of 12 tombs were determined, yielding the
Cheek teeth of extinct primates. Refer to the American Journal of Physical Anthropology (Vol. 142, 2010) study of the characteristics of cheek teeth (e.g., molars) in an extinct primate species, Exercise 2.38(p. 78). Recall that the researchers recorded the dentary depth of molars (in millimeters)
Shell lengths of sea turtles. Refer to the Aquatic Biology (Vol. 9, 2010) study of green sea turtles inhabiting the Grand Cayman South Sound lagoon, Exercise 7.24(p. 354). Recall that the data on shell length, measured in centimeters, for 76 captured turtles are saved in the TURTLES file. Use the
Lobster trap placement. Refer to the Bulletin of Marine Science (Apr. 2010) study of red spiny lobster trap placement, Exercise 7.41(p. 363). Trap spacing measurements(in meters) for a sample of seven teams of red spiny lobster fishermen are repeated in the table below. The researchers want to know
Is honey a cough remedy? Refer to the Archives of Pediatrics and Adolescent Medicine (Dec. 2007) study of honey as a remedy for coughing, Exercise 2.40(p. 79).Recall that the 105 ill children in the sample were randomly divided into groups. One group received a dosage of an over-the-counter cough
Phishing attacks to e-mail accounts. Refer to the Chance(Summer 2007) study of an actual phishing attack against an organization, Exercise 6.36(p. 330). Recall that phishing describes an attempt to extract personal/financial information from unsuspecting people through fraudulent e-mail.The
Interpret the phrase “95% confident” in the following statement: “We are 95% confident that the proportion of all PCs with a computer virus falls between .12 and .18.”
For each of the following, identify the target parameter as m, p, or s2.a. Average score on the SATb. Mean time waiting at a supermarket checkout lanec. Proportion of voters in favor of legalizing marijuanad. Percentage of NFL players who have ever made the Pro Bowle. Dropout rate of American
In each of the following instances, determine whether you would use a z- or t-statistic (or neither) to form a 99% confidence interval for m; then look up the appropriate z or t value.a. Random sample of size n = 17 from a normal distribution with unknown mean m and standard deviation sb. Random
Use Table IV, Appendix B, or statistical software to find xa>2 2 and x1 - a>2 2 for each of the following:a. n = 10, a = .05b. n = 20, a = .05c. n = 50, a = .01
Let t0 represent a particular value of t from Table III of Appendix B. Find the table values such that the following statements are true:a. P1t … t02 = .05, where df = 14b. P1t Ú t02 = .005, where df = 19c. P1t … -t0 or t Ú t02 = .10, where df = 9d. P1t … -t0 or t Ú t02 = .01, where df = 28
In a random sample of 225 measurements, 125 possess the characteristic of interest, A.a. Use a 95% confidence interval to estimate the true proportion p of measurements in the population with characteristic A.b. How large a sample would be needed to estimate p to within .02 with 95% confidence?
A random sample of 400 measurements is selected from a population, and the sample mean and standard deviation are x = 40.5 and s = 26.0, respectively.a. Use a 99% confidence interval to estimate the mean of the population, m.b. How large a sample would be needed to estimate m to within .5 with 99%
CDC health survey. The Centers for Disease Control and Prevention (CDCP) in Atlanta, Georgia, conduct an annual survey of the general health of the U.S. population as part of their Behavioral Risk Factor Surveillance System.Using random-digit dialing, the CDCP telephones U.S.citi zens over 18 years
Personal networks of older adults. In sociology, a personal network is defined as the people with whom you make frequent contact. A stratified random sample of men and women born between 1908 and 1937 was used to gauge the size of the personal network of older adults. Each adult in the sample was
Ancient Greek pottery. Refer to the Chance (Fall 2000)study of 837 pieces of pottery found at the ancient Greek settlement at Phylakopi, presented in Exercise 2.186(p. 134). Of the 837 pieces, 183 were painted with either a curvilinear, geometric, or naturalistic decoration. Find a 90% confidence
Extinct New Zealand birds. Refer to the Evolutionary Ecology Research (July 2003) study of the patterns of extinction in the New Zealand bird population, presented in Exercise 2.108(p. 106). Suppose you are interested in estimating the mean egg length (in millimeters) for the New Zealand bird
Scanning errors at Wal-Mart. Refer to the National Institute for Standards and Technology (NIST) study of the accuracy of checkout scanners at Wal-Mart stores in California, presented in Exercise 3.56(p. 169). NIST sets standards so that no more than 2 of every 100 items scanned through an
Speed training in football. Refer to The Sport Journal(Winter 2004) study on the effectiveness of a speed-training program for football players, Exercise 7.26(p. 354). The decreases in 40-yard sprint times (time after training minus time before training) for 38 players are saved in the SPRINT file.
Assessing the bending strength of a wooden roof. The white wood material used for the roof of an ancient Japanese temple is imported from Northern Europe. The wooden roof must withstand as much as 100 centimeters of snow in the winter. Architects at Tohoku University (in Japan)conducted a study to
Water pollution testing. The EPA wants to test a randomly selected sample of n water specimens and estimate m, the mean daily rate of pollution produced by a mining operation.If the EPA wants a 95% confidence interval estimate with a sampling error of 1 milligram per liter (mg/L), how many water
Radioactive lichen. Refer to the Lichen Radionuclide Baseline Research project at the University of Alaska, presented in Exercise 2.196(p. 136). Recall that the researchers collected 9 lichen specimens and measured the amount (in microcuries per milliliter) of the radioactive element cesium-137 for
Attention time given to twins. Psychologists have found that twins, in their early years, tend to have lower IQs and pick up language more slowly than nontwins (Wisconsin Twin Research Newsletter, Winter 2004). The slower intellectual growth of most twins may be caused by benign parental neglect.
Oven cooking study. A group of Harvard University School of Public Health researchers studied the impact of cooking on the size of indoor air particles (Environmental Science& Technology, Sept. 1, 2000). The decay rate (measured in mm>hour) for fine particles produced from oven cooking or
Scary-movie study. According to a University of Michigan study, many adults have experienced lingering “fright” effects from a scary movie or TV show they saw as a teenager. In a survey of 150 college students, 39 said they still experience“residual anxiety” from a scary TV show or movie.a.
Brown-bag lunches at work. In a study reported in The Wall Street Journal, the Tupperware Corporation surveyed 1,007 U.S. workers. Of the people surveyed, 665 indicated that they take their lunch to work with them. Of these 665 taking their lunch, 200 reported that they take it in brown bags.a.
Research on brain specimens. In Exercise 2.45(p. 80), you learned that the postmortem interval (PMI) is the elapsed time between death and the performance of an autopsy on the cadaver. Brain and Language (June 1995) reported on the PMIs of 22 randomly selected human brain specimens obtained at
Inbreeding of tropical wasps. Tropical swarm-founding wasps rely on female workers to raise their offspring.One possible explanation for this strange behavior is inbreeding, which increases relatedness among the wasps, presumably making it easier for the workers to pick out their closest relatives
Exercise workout dropouts. Researchers at the University of Florida’s Department of Exercise and Sport Sciences conducted a study of variety in exercise workouts (Journal of Sport Behavior, 2001). A sample of 120 men and women were randomly divided into three groups, with 40 people per group.
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