1. [-12 Points] BBBASICSTAT8 1.R.010. A radio talk show host asked listeners to respond either yes or no to the question, "Is the candidate who spends the most on a campaign the most likely to win?" Fifteen people called in and nine said yes. What is the implied population? ' ' all adults ' all radio listeners " all callers " all listeners of the radio talk show What is the variable? " number of callers " number of listeners opinion of a listener " opinion of a caller Can you detect any bias in the selection of the sample? " Yes, there is a systematic bias against those that are not listening to the talk show. No, there is no bias in the selection of this sample. ' Yes, voluntary response. Those with the strongest opinions are most likely to call in. '\\ Yes, nonresponse. Many listeners may not call in. 2. [-I2.27 Points] DETAILS BBBASICSTAT8 1.R.009. MY NOTES I You are conducting a study of students doing work-study jobs on your campus. Among the questions on the survey Instrument are the follownng. A. How many hours are you scheduled to work each week? Answer to the nearest hour. B. How applicable is this work experience to your future employment goals? Respond using the following scale: 1: not at all, 2 = somewhat, 3 = very (a) Suppose you take random samples from the following groups: freshmen, sophomores, juniors, and seniors. What kind of sampling technique are you using (simple random, stratied, systematic, cluster, multistage, convenience)? ' ' cluster sample systematic sample convenience sample " simple random sample stratified sample " multistage sample (b) Describe the individuals of this study. " Students on all campuses with work-study jobs. ' Students on your campus. " Students on your campus with work-study jobs. ' Studenls on all campuses. (c) What is the variable for question A? ' ' type of job hours scheduled number of students who work " total hours worked Classify the variable as qualitative or quantitative. neither quantitative nor qualitative Classify the variable as qualitative or quantitative. " neither quantitative nor qualitative both qualitative and quantitative qualitative quantitative What is the level of measurement? ratio \\ interval ' \\ ordinal " nominal (d) What is the variable for question B? ' ' rating of applicability of work experience to future employment ' rating of satisfaction of work experience for future employment hours scheduled number of students who work Classify the variable as qualitative or quantitative. neither quantitative nor qualitative quantitative qualitative ' ' both qualitative and quantitative What is the level of measurement? ratio ' interval ' ' ordinal ' nominal (e) Is the proportion of responses "3 = very\" to question B a statistic or a parameter? neither a statistic nor a parameter 1.... a \"yummy-t. and a inhabit-bi;- Classify the variable as qualitative or quantitative. neither quantitative nor qualitative quantitative qualitative both qualitative and quantitative What is the level of measurement? " ratio ' ' interval ordinal nominal (e) Is the proportion of responses "3 = very\" to question B a statistic or a parameter? " neither a statistic nor a parameter both a parameter and a statistic statistic parameter (f) Suppose only 40% of the students you selected for the sample respond. What is the nonresponse rate? % Do you think the nonresponse rate might introduce bias into the study? Explain. No, the people choosing not to respond probably don't have characteristics that would bias the study. " Yes, the people choosing to respond may have some characteristics that would bias the study. No, the people choosing to respond probably don't have characteristics that would bias the study. Yes, the people choosing not to respond may have some characteristics that would bias the study. (9) Would it be appropriate to generalize the results of your study to all work-study students in the nation? Explain. " No, the sample frame is restricted to one campus. Yes, the sample is random so the results can be applied anywhere. Yes, the sample frame is for all campuses. No, results only apply to the students sampled. 3. [-/2.27 Points] DETAILS BBBASICSTAT8 2.R.016.S. MY NOTES Many people say the civil justice system is overburdened. Many cases center on suits involving businesses. The following data are based on a Wall Street Journal report. Researchers conducted a study of lawsuits involving 1908 businesses ranked in the Fortune 1000 over a 20-year period. They found the following distribution of civil justice caseloads brought before the federal courts involving the businesses. Note: Contracts cases involve disputes over contracts between businesses. (SALT uses C for "Contracts," GT for "General torts (personal injury)", AL for "Asbestos liability," OPL for "Other product liability," and AO for "All other.") Number of Filings Case Type (in thousands) Contracts 107 General torts (personal injury) 191 Asbestos liability 49 Other product liability 38 All other 21 In USE SALT (a) Make a Pareto chart of the caseloads. 200 2007 107 180 180 160 160 140 140 2 120 120 107 191 100 100 80- 80 60 60 49 38 40 40 21 21 20 20 O Gen tris Cntrots Asbets Othr pract All othr O Gen tris Cntrots Asbets Othr pract All othr 200 7 107 200 191 180 180 160 160 140 140 120 120200 191 200 107 180 180 160 160 140 140 1 120 107 9 120 191 ings 100 100 Filings 80 80 60 60 49 38 40 38 UV 49 21 21 20 20 O Gen tris Cntrots Asbets Othr pract All othr O Gen tris Cntrots Asbsts Other pract All othr 2007 107 200 191 180 180 160 160 140 140 120 191 107 Ings Filings 100 100 80 7 80 60 60 38 49 40 49 40 38 21 21 20 O Cntrots Gentrts Oth prdot Asbsts All othr O Cntrcts Gentrts Othr pract Asbsts All othr Which type of cases occur most frequently? all other contracts general torts O asbestos liability O other product liabilityWhich type of cases occur most frequently? all other contracts " general torts asbestos liability other product liability (b) Make a pie chart showing the percentage of cases of each type. (b) Make a pie chart showing the percentage of cases of each type. 4. [-l2.16 Points] BBBASICSTAT8 3.R.012.S. Radon he Problem No One Wants to Face\" is the title of an article appearing in Consumer Reports. Radon is a gas emitted from the ground that can collect in houses and buildings. At certain levels it can cause lung cancer. Radon concentrations are measured in picocuries per liter (pCi/L). A radon level of 4 pCi/L is considered "acceptable." Radon levels in a house vary from week to week. In one house, a sample of 8 weeks had the following readings for radon level (in pCi/L). 1.9 2 5.7 4.6 1.9 8.1 3.9 7.8 la use SALT (a) Find the mean, median, and mode. mean median mode (b) Find the sample standard deviation, coefcient of variation, and range. (Round your standard deviation to four decimal places and your coefcient of variation to two decimal places.) S CV % range (c) Based on the data, would you recommend radon mitigation in this house? Explain. Yes, since the median value is over "acceptable" ranges, although the mean value is not. No, since the average and median values are both under "acceptable\" ranges. " Yes, since the average and median values are both over "acceptable\" ranges. " Yes, since the average value is over "acceptable" ranges, although the median value is not. when using the least-squares line for prediction, are results more reliable for extrapolation or interpolation? Interpolation, because we are predicting from data outside the range used to create the least-squares line. ' ' Interpolation, because we are predicting from data in the range used to create the least-squares line. '\\ Extrapolation, because we are predicting from data in the range used to create the least-squares line. '\\ Extrapolation, because we are predicting from data outside the range used to create the least-squares line. 6. [I4 Points] BBBASICSTAT8 4.R.009.S. Bighorn sheep are beautiful wild animals found throughout the western United States. Letx be the age of a bighorn sheep (in years), and let y be the mortality rate (percent that die) for this age group. For example, X = 1, y = 14 means that 14% of the bighorn sheep between 1 and 2 years old died. A random sample of Arizona bighorn sheep gave the following information: x 1 2 3 4 5 y 12.0 20.3 14.4 19.6 20.0 I USE SA 2x = 15; By = 86.3; 2x2 = 55; XyZ = 1,547.61; Exy = 274.2 (a) Find )7, I], b, and the equation of the least-squares line. (Round your answers for)? and I, to two decimal places. Round your leastsquares estimates to three decimal places.) )7 = O- ' 13.5 O Ho: p = 13.5; H1: p # 13.5 O Ho: M = 13.5; H1: M 13.5 O Ho: M = 13.5; H1: M # 13.5 O Ho: p = 13.5; H1: p 0.500 O 0.250 0.500 0.250