DR. GRAMLING BUAL 2600 FINAL EXAM QUESTIONS AND ANSWERS 2024/2025

DR. GRAMLING BUAL 2600 FINAL EXAM QUESTIONS AND ANSWERS 2024/2025 A normal distribution with mean equal to zero and a standard deviation equal to one is called the ________ normal distribution. a. continuous b. standard c. uniform d. exponential - RIGHT ANSWER -b. standard HW #10 A standard normal distribution has a mean of ________ and standard deviation of ________. a. one, one b. zero, one c. one, zero d. zero, zero - RIGHT ANSWER -b. zero, one HW #10 A(n) ________ is a collection of sample space outcomes. a. event b. set c. experiment d. probability - RIGHT ANSWER -a. event HW #10 Given that the length an athlete throws a hammer is a normal random variable with mean 50 feet and standard deviation 5 feet, what is the probability he throws it no less than 55 feet? a. .8413 b. .6826 c. .3174 d. .1587 - RIGHT ANSWER -d. .1587 HW #10 Given that X is a normal random variable, the probability that a given value of X is below its mean is ________. a. 1 b. less than .5 c. greater than .5 d. equal to .5 - RIGHT ANSWER -d. equal to .5 HW #10 Probabilities must be assigned to each sample space outcome so that the probabilities of all the sample space outcomes add up to ________. a. 0 b. 1 c. between 0 and 1 d. between −1 and 1 - RIGHT ANSWER -b. 1 HW #10 Probabilities must be assigned to sample space outcomes so that the probability assigned to each sample space outcome must be between ________, inclusive. a. −1 and 1 b. 0 and 1 c. −100 and 100 b. 0 and 100 - RIGHT ANSWER -b. 0 and 1 HW #10 T/F: For a continuous distribution, P(X ≤ 100) = P(X < 100). - RIGHT ANSWER -True HW #10 T/F: In any probability situation, either an event or its complement must occur. - RIGHT ANSWER -True HW #10 T/F: The mean and median are the same for a normal distribution. - RIGHT ANSWER -True HW #10 The ________ of an event is a number that measures the likelihood that an event will occur when an experiment is carried out. a. outcome b. observation c. intersection d. probability - RIGHT ANSWER -d. probability HW #10 The fill weight of a certain brand of adult cereal is normally distributed with a mean of 910 grams and a standard deviation of 5 grams. We calculated the value of z for a specific box of this brand of cereal, and the z value was negative. This negative z value indicates that a. the fill weight may be more or less than 910 grams depending on the value of the standard deviation. b. we made a mistake in our calculations, as z must always be a nonnegative number. c. the fill weight is more than 910 grams. d. the fill weight is less than 910 grams. e. the fill weight is equal to 910 grams. - RIGHT ANSWER -d. the fill weight is less than 910 grams. HW #10 The flying time of a drone airplane has a normal distribution with mean 4.76 hours and standard deviation of .04 hours. What is the probability that the drone will fly less than 4.66 hours? a. .9938 b. −.0062 c. .5062 d. .0062 - RIGHT ANSWER -d. .0062 HW #10 The grade a student received on an examination was transformed to a z value, which was negative. Therefore, we know that he scored a. below the mean. b. lower than 16 percent of the class. c. above the first quartile. d. higher than 16 percent of the class. e. higher than 45 percent of the class. - RIGHT ANSWER -a. below the mean. HW #10 What is the probability that a standard normal random variable will be between .3 and 3.2? a. .9993 b. .3814 c. .6179 d. .3808 - RIGHT ANSWER -b. .3814 HW #10 A process of observation that has an uncertain outcome is referred to as a(n) ________. a. conditional probability b. frequency c. probability d. experiment - RIGHT ANSWER -d. experiment HW #10 Consider a normal population with a mean of 10 and a variance of 4. Find P(X > 7). a. .9332 b. .0668 c. .8413 d. .1587 - RIGHT ANSWER -a. .9332 HW #10 The ________ of event X consists of all sample space outcomes that do not correspond to the occurrence of event X. a. conditional probability b. complement c. dependence d. independence - RIGHT ANSWER -b. complement HW #10 The area under the curve of a valid continuous probability distribution must ________. a. be less than 1 b. be infinite c. equal 1 d. be between 0 and 1 - RIGHT ANSWER -c. equal 1 HW #10 The set of all possible outcomes for an experiment is called a(n) ________. a. experiment b. event c. sample space d. probability - RIGHT ANSWER -c. sample space HW #11 A ________ is a measure of the chance that an uncertain event will occur. a. population b. probability c. random experiment d. complement e. sample space - RIGHT ANSWER -b. probability HW #11 As the margin of error decreases, the width of the confidence interval ________. a. stays the same b. decreases c. increases - RIGHT ANSWER -b. decreases HW #11 As the sample size n increases, the width of the confidence interval ________. a. increases b. decreases c. stays the same - RIGHT ANSWER -b. decreases HW #11 Consider a normal population with a mean of 10 and a variance of 4. Find P(X < 6). a. .0228 b. .9772 c. .1587 d. .8413 - RIGHT ANSWER -a. .0228 HW #11 Consider a normal population with a mean of 10 and a variance of 4. Find P(X > 18). a. 1.00 b. .0228 c. .00 d. .9772 - RIGHT ANSWER -c. .00 HW #11 Consider a normal population with a mean of 10 and a variance of 4. Find P(X ≥ 10). a. .50 b. 1.00 c. −.50 d. .00 - RIGHT ANSWER -a. .50 HW #11 Given that the length an athlete throws a hammer is a normal random variable with mean 50 feet and standard deviation 5 feet, what is the probability he throws it between 50 feet and 60 feet? a. .9544 b. .9972 c. .4772 d. .5000 - RIGHT ANSWER -c. .4772 HW #11 If the random variable x is normally distributed, ______ percent of all possible observed values of x will be within three standard deviations of the mean. a. None of these answers are correct. b. 68.26 c. 95.44 d. 100 e. 99.73 - RIGHT ANSWER -e. 99.73 HW #11 In 2005, 13,000 Internet users were surveyed and asked about their willingness to pay fees for access to websites. Of these, 2,938 were definitely not willing to pay such fees. Construct a 95 percent confidence interval for the proportion definitely unwilling to pay fees. a. [.220, .232] b. [.219, .233] c. [.214, .245] d. [.286, .302] e. [.212, .241] - RIGHT ANSWER -b. [.219, .233] HW #11 In a randomly selected group of 650 automobile deaths, 180 were alcohol related. Construct a 95 percent confidence interval for the true proportion of all automobile accidents caused by alcohol. a. [.243, .311] b. [.263, .291] c. [.259, .294] d. [.262, .292] - RIGHT ANSWER -a. [.243, .311] HW #11 Recently, a case of food poisoning was traced to a particular restaurant chain. The source was identified, and corrective actions were taken to make sure that the food poisoning would not reoccur. Despite the response from the restaurant chain, many consumers refused to visit the restaurant for some time after the event. A survey was conducted three months after the food poisoning occurred, with a sample of 319 former customers contacted. Of the 319 contacted, 29 indicated that they would not go back to the restaurant because of the potential for food poisoning. Construct a 95 percent confidence interval for the true proportion of the market who still refuse to visit any of the restaurants in the chain three months after the event. a. [.059, .122] b. [.000, .196] c. [.240, .339] d. [.118, .244] e. [.090, .091] - RIGHT ANSWER -a. [.059, .122] HW #11 T/F: If the random variable, x, is normally distributed, 68.26 percent of all possible observed values of x will be within two standard deviations of the mean. - RIGHT ANSWER -False HW #11 T/F: The z value tells us the number of standard deviations that a value, x, is from the mean. - RIGHT ANSWER -True HW #11 The internal auditing staff of a local lawn-service company performs a sample audit each quarter to estimate the proportion of accounts that are delinquent (more than 90 days overdue). For this quarter, the auditing staff randomly selected 400 customer accounts and found that 80 of these accounts were delinquent. What is the 95 percent confidence interval for the proportion of all delinquent customer accounts at this company? a. .1485 to .2515 b. .1992 to .2008 c. .1671 to .2329 d. .1608 to .2392 e. .1714 to .2286 - RIGHT ANSWER -d. .1608 to .2392 HW #11 The population of lengths of aluminum-coated steel sheets is normally distributed with a mean of 30.05 inches and a standard deviation of .2 inches. What is the probability that a sheet selected at random from the population is between 30.25 and 30.65 inches long? a. .8413 b. .1587 c. .1574 d. .9987 - RIGHT ANSWER -c. .1574 HW #11 The population of lengths of aluminum-coated steel sheets is normally distributed with a mean of 30.05 inches and a standard deviation of .2 inches. What is the probability that a sheet selected at random will be less than 31 inches long? a. 1.00 b. .8289 c. .5987 d. .00 - RIGHT ANSWER -a. 1.00 HW #11 The relationship between the standard normal random variable, z, and normal random variable, X, is that a. the values of the standard normal random variable z cannot be negative. b. only the normal random variable X is continuous. c. only the standard normal variable z is continuous. d. the standard normal variable z counts the number of standard deviations that the value of the normal random variable X is away from its mean. e. the values of the normal random variable X cannot be negative. - RIGHT ANSWER -d. the standard normal variable z counts the number of standard deviations that the value of the normal random variable X is away from its mean. HW #11 The specific shape of each normal distribution is determined by its ________ and ________. a. mean, variance b. mean, standard deviation c. median, standard deviation d. median, variance - RIGHT ANSWER -b. mean, standard deviation HW #11 The state agriculture department tested 203 fuel samples across the state in 2009 for accuracy of the reported octane level. For premium grade, 14 out of 105 samples failed. Find a 99 percent confidence interval for the true population proportion of premium grade fuel-quality failures. a. [.100, .276] b. [.045, .221] c. [.048, .219] d. [.068, .198] e. [.023, .115] - RIGHT ANSWER -c. [.048, .219] HW #11 The success rate of an experimental medical procedure is 37 per 120 cases in a sample. Find a 95 percent confidence interval for the actual success proportion of the procedure. a. [.2260, .3910] b. [.2836, .4564] c. [.2975, .4425] d. [.2389, .3776] - RIGHT ANSWER -a. [.2260, .3910] HW #11 The weight of a product is normally distributed with a mean of 4 ounces and a variance of .25 squared ounces. What is the probability that a randomly selected unit from a recently manufactured batch weighs more than 3.75 ounces? a. .1587 b. .8413 c. .3085 d. .6915 - RIGHT ANSWER -d. .6915 HW #11 The weight of a product is normally distributed with a mean of 4 ounces and a variance of .25 squared ounces. What is the probability that a randomly selected unit from a recently manufactured batch weighs more than 5 ounces? a. .0228 b. 1.00 c. .000 d. .9772 - RIGHT ANSWER -a. .0228 HW #11 When a confidence interval for a population proportion is constructed for a sample size n = 30 and the value of pˆp^ = .4, the interval is based on a. the Poisson distribution. b. the exponential distribution. c. the z distribution. d. the t distribution. e. None of these answers is correct. - RIGHT ANSWER -c. the z distribution HW #11 The flying time of a drone airplane has a normal distribution with mean 4.76 hours and standard deviation of .04 hours. What is the probability that the drone will fly more than 4.80 hours? a. .6587 b. .3413 c. .8413 d. .1587 - RIGHT ANSWER -d. .1587 HW #2 A ________ variable takes on values that are numbers on the real number line. a. quantitative b. nominative c. qualitative d. categorical - RIGHT ANSWER -a. quantitative HW #2 A commercial shipping company operates a large fleet of trucks. The company needs to collect data on vehicle usage including acceleration, braking, and vehicle maintenance such as fluid levels. The datasourcing method needed to collect the data for this scenario is... a. Point of Sale b. None of these c. Clickstream d. Sensor e. Social Media - RIGHT ANSWER -d. sensor HW #2 A doctor's office needs to know how many of their services are used by their patients during a one year time period. Before a patient leaves their office, a summary report includes the date, the doctor they saw, the services provided, and the total charge for each service. Which of the following datasourcing methods best describes this data collection scenario? a. None of these b. Survey c. Point of Sale d. Clickstream e. Social Media f. Observation - RIGHT ANSWER -c. point of sale HW #2 A person's telephone area code is an example of a(n) ________ variable. a. ordinal b. ratio c. nominative d. interval - RIGHT ANSWER -c. nominative HW #2 A(n) ________ variable can have values that indicate into which of several categories of a population it belongs. a. qualitative b. quantitative c. interval d. ratio - RIGHT ANSWER -a. qualitative HW #2 A(n) ________ variable is a qualitative variable such that there is no meaningful ordering or ranking of the categories. a. ratio b. nominative c. interval d. ordinal - RIGHT ANSWER -b. nominative HW #2 An identification of police officers by rank would represent a(n) ________ level of measurement. a. nominative b. ratio c. ordinal d. interval - RIGHT ANSWER -c. ordinal HW #2 Classify each of the following qualitative variables as ordinal or nominative. a. Statistics course letter grade: A, B, C, D, F b. Door choice on Let's Make A Deal: Door #1, Door #2, Door #3 c. Television show classifications: TV-G, TV-PG, TV-14, TV-MA d. Personal computer ownership: Yes, No e. Restaurant rating: *****, ****, ***, **, * f. Income tax filing status: Married filing jointly; Married filing separately; Single; Head of household; Qualifying widow(er) - RIGHT ANSWER -a. ordinal b. nominative c. ordinal d. nominative e. ordinal f. nominative HW #2 In the Analytic Process, the next step after the descriptives (descriptives is the data that has occurred up to the current point in time) have been collected, is to use the data to... a. Make an actionable decision b. Conduct a random sample c. None of these d. Make predictions e. Ask the next question - RIGHT ANSWER -d. Make predictions HW #2 Measurements from a population are called... a. processes. b. variables. c. observations. d. elements. - RIGHT ANSWER -c. observations. HW #2 Possible qualitative data for Stitchfix to collect is a clothing size such as small, medium, and large. This is an example of __________ (ordinal, nominal, discrete, or continuous) variable. a. ordinal b. nominal c. discrete d. continuous - RIGHT ANSWER -a. ordinal HW #2 T/F: A quantitative variable can also be referred to as a categorical variable. - RIGHT ANSWER -False HW #2 T/F: An example of a qualitative variable is the mileage of a car. - RIGHT ANSWER -False HW #2 T/F: Business analytics is a new field that does not use traditional statistics to analyze big data. - RIGHT ANSWER -false HW #2 Which of the following describes the steps of the Analytic Process after we know the business problem? a. Collect Descriptives-Choose Sampling Method-Make Prediction-Ask Next Question b. Collect Descriptives-Ask the Next Question-Choose Sampling Method-Make Prediction c. Choose DataSourcing Method-Choose Sampling Method-Collect Descriptives-Make Prediction-Ask Next Question d. Choose DataSourcing Method-Collect Descriptives-Make Prediction-Ask Next Question e. None of these f. Choose Sampling Method-Choose DataSourcing Method-Make Prediction-Ask Next Question - RIGHT ANSWER -d. Choose DataSourcing Method-Collect Descriptives-Make Prediction-Ask Next Question HW #2 Which of the following is a quantitative variable? a. whether a person has a charge account b. mileage of a car c. a person's gender d. the manufacturer of a cell phone e. whether a person is a college graduate - RIGHT ANSWER -b. milage of a car HW #2 Which of these variables are quantitative and which are qualitative? a. The dollar amount on an accounts receivable invoice. b. The net profit for a company in 2017. c. The stock exchange on which a company's stock is traded. d. The national debt of the United States in 2017. e. The advertising medium (radio, television, or print) used to promote a product. - RIGHT ANSWER -a. quantitative b. quantitative c. qualitative d. quantitative e. qualitative HW #3 A ________ is a subset of the units in a population. a. census b. process c. sample d. variable - RIGHT ANSWER -c. sample HW #3 ________ occurs when some population elements are excluded from the process of selecting the sample. a. Error of observation b. Sample frame c. Nonresponse d. Undercoverage - RIGHT ANSWER -d. Undercoverage HW #3 A local store wants to find out if a new item is linked by their customers. They ask the first 10 customers that enter the store and use only this data. This is an example of _________ sampling. a. Cluster b. Simple Random c. Response d. Convenient e. Stratified Random - RIGHT ANSWER -d. Convenient HW #3 A set of all elements we wish to study is called a ________. a. sample b. process c. census d. population - RIGHT ANSWER -d. population HW #3 Amazon collects random reviews from their customers on the West Coast as the data they use for their nationwide marketing plan. This sample suffers from which sampling bias? a. Response Bias b. Undercoverage c. Recording Error d. Nonresponse Error - RIGHT ANSWER -b. Undercoverage HW #3 By randomly selecting a starting point then choosing every 50th person, we are conducting a ________ random sample. - RIGHT ANSWER -systematic HW #3 Examining all population measurements is called ________. a. sample b. frame c. variable d. census - RIGHT ANSWER -d. census HW #3 In ________ we select elements because they are easy to sample. a. random sampling b. judgment sampling c. convenience sampling d. probability sampling - RIGHT ANSWER -c. convenience sampling HW #3 Nonoverlapping groups of similar elements in a population are called a. stages. b. clusters. c. frames. d. strata. - RIGHT ANSWER -d. strata. HW #3 StitchFix has 1000 customers they sampled by age. They should use _________ random sampling to randomly select 50 customers from each age group. - RIGHT ANSWER -stratified HW #3 StitchFix wants to make sure different specific characteristics, such as all different age groups, are represented in their sample. The appropriate sampling method they should use is: a. Voluntary Sampling b. Systematic Sampling c. Cluster Sampling d. Convenient Sampling e. Simple Random Sampling f. Stratified Random Sampling - RIGHT ANSWER -f. Stratified Random Sampling HW #3 T/F: A common practice in selecting a sample from a large geographic area is multistage cluster sampling. - RIGHT ANSWER -true HW #3 T/F: A low response rate has no effect on the validity of a survey's findings. - RIGHT ANSWER -false HW #3 T/F: A population is a set that includes all elements about which we wish to draw a conclusion. - RIGHT ANSWER -true HW #3 T/F: A quantitative variable can also be referred to as a categorical variable. - RIGHT ANSWER -false HW #3 T/F: A random sample is selected so that every element in the population has the same chance of being included in the sample. - RIGHT ANSWER -true HW #3 T/F: A recording error is an error of observation. - RIGHT ANSWER -true HW #3 T/F: By taking a systematic sample in which we select every 100th shopper arriving at a specific store, we are approximating a random sample of shoppers. - RIGHT ANSWER -true HW #3 T/F: Convenience sampling is a type of probability sampling in which we select elements to sample because we believe they have the highest probability of responding. - RIGHT ANSWER -false HW #3 T/F: Errors of non-observation occur when data values are recorded incorrectly. - RIGHT ANSWER -false HW #3 T/F: If we examine some of the population measurements, we are conducting a census of the population. - RIGHT ANSWER -false HW #3 T/F: In order to select a stratified random sample, we divide the population into overlapping groups of similar elements. - RIGHT ANSWER -false HW #3 T/F: In systematic sampling, the first element is randomly selected from the first (N/n) elements. - RIGHT ANSWER -true HW #3 T/F: It is possible to use a random sample from a population to make statistical inferences about the entire population. - RIGHT ANSWER -true HW #3 T/F: Sampling error occurs because a characteristic of a random sample may not exactly equal the population characteristic that we are attempting to estimate. - RIGHT ANSWER -true HW #3 T/F: Stratification can at times be combined with multistage cluster sampling to develop an appropriate sample. - RIGHT ANSWER -true HW #3 The 2020 Presidential Election was in November and we saw reports on the percentage of Americans who were registered to vote in the national. If we wanted to sample all registered to vote in the national election. If we wanted to sample all registered voters in the United States and avoid bias, as well as, save time and money, the appropriate sampling method to use would be: a. Stratified Random Sampling by States b. Systematic Random Sampling of registered voters c. Cluster Random Sampling by regions nationwide d. Simple Random Sampling of registered voters e. Voluntary Sampling by States - RIGHT ANSWER -c. Cluster Random Sampling by regions nationwide HW #3 The purpose of collecting a random sample from a population is: a. to make statistical inferences about the entire population b. to ask the next question c. to replicate the population d. to create a census - RIGHT ANSWER -a. to make statistical inferences about the entire population HW #3 When a low response bias occurs, what should you do? a. Conduct another sample to increase the response rate b. Report whatever data was collected Ask a different question c. Conduct a convenient sample d. Nothing can be done to correct this bias - RIGHT ANSWER -a. Conduct another sample to increase the response rate HW #3 When a person gives an answer that they think you want to hear or is politically correct, this is an example of which bias: a. Measurement Error b. Undercoverage c. Recording Error - RIGHT ANSWER -a. Measurement Error HW #3 Which of the following questions would result in Response Bias? a. Would you attend a cooking demonstration? b. What do you think is the best way to remove trash from our waterways? c. Would you prefer to eat a steak or a peanut butter sandwich? d. Since hacking is so common, are you confident that the information you provide online is secure? e. None of the questions would result in a bias - RIGHT ANSWER -d. Since hacking is so common, are you confident that the information you provide online is secure? HW #4 The number of measurements falling within a class interval is called the ________. a. leaf b. frequency c. relative frequency d. cumulative sum - RIGHT ANSWER -b. frequency HW #4 ________ and ________ are used to describe qualitative (categorical) data. a. Pie charts, histograms b. Bar charts, pie charts c. Scatter plots, histograms d. Stem-and-leaf displays, scatter plots e. Dot plots, bar charts - RIGHT ANSWER -b. Bar charts, pie charts HW #4 822 recently purchased books were randomly selected from all recent book purchases over the Internet. The chart below shows the breakdown of the classification of the book type. What percentage of the books in the sample were either mystery or science fiction/fantasy? 1. top 50 fiction: 189 2. children's books: 168 3. mystery: 153 4. sci/fi: 147 5. self-help books: 94 6. biographies: 34 7. classical books: 22 8. textbooks: 15 a. 24.33 b. 22.99 c. 18.61 d. 36.50 e. 17.88 - RIGHT ANSWER -d. 36.50 HW #4 822 recently purchased books were randomly selected from all recent book purchases over the Internet. The chart below shows the breakdown of the classification of the book type. What percentage of the books in the sample were self-help books? 1. top 50 fiction: 189 2. children's books: 168 3. mystery: 153 4. sci/fi: 147 5. self-help books: 94 6. biographies: 34 7. classical books: 22 8. textbooks: 15 a. 0.940 b. 11.44 c. 1.82 d. .1144 e. 0.0182 - RIGHT ANSWER -b. 11.44 HW #4 A multiple choice question on an exam has four possible responses—(A), (B), (C), and (D). When 250 students take the exam, 100 give response (A), 25 give response (B), 75 give response (C), and 50 give response (D). a. Write out the frequency distribution, relative frequency distribution, and percent frequency distribution for these responses. (Round your relative frequency answers to 2 decimal places.) b. Choose the bar chart for this data using frequencies. - RIGHT ANSWER -a.) a. freq: 100; relative freq: 0.40; % freq: 40 b. freq: 25; relative freq: 0.10; % freq: 10 c. freq: 75; relative freq: 0.30; % freq: 30 d. freq: 50; relative freq: 0.20 % freq: 20 b.) figure A is correct HW #4 A multiple choice question on an exam has four possible responses—(A), (B), (C), and (D). When 300 students take the exam, 150 give response (A), 30 give response (B), 90 give response (C), and 30 give response (D). A. Write out the frequency distribution, relative frequency distribution, and percent frequency distribution for these responses. (Round your relative frequency answers to 2 decimal places.) - RIGHT ANSWER -a. freq: 150; relative freq: 0.50; % freq: 50 b. freq: 30; relative freq: 0.10; % freq: 10 c. freq: 90; relative freq: 0.30; % freq: 30 d. freq: 30; relative freq: 0.10 % freq: 10 HW #4 A Yes or No question is ________. a. open-ended b. systematic c. dichotomous d. evaluative - RIGHT ANSWER -c. dichotomous HW #4 At the end of their final exam, 550 students answered an additional question in which they rated their instructor's teaching effectiveness, with the following results. What proportion of the students who rated their instructor as very or somewhat effective received a C or lower in the class? 1. A; effective: 190; ineffective: 85 2. B; effective: 75; ineffective: 120 3. C; effective: 20; ineffective: 17 4. D; effective: 9; ineffective: 18 5. F; effective: 1; ineffective: 15 a. 0.10 b. 0.13 c. 0.03 d. 0.15 e. 0.06 - RIGHT ANSWER -a. 0.10 HW #4 Below we give the overall dining experience ratings (Outstanding, Very Good, Good, Average, or Poor) of 30 randomly selected patrons at a restaurant on a Saturday evening. Outstanding, Good, Very Good, Very Good, Outstanding, Good, Outstanding Outstanding, Outstanding, Very Good, Very Good, Average, Very Good, Outstanding, Outstanding, Outstanding, Outstanding, Very Good, Outstanding, Good, Very Good, Outstanding, Very Good, Outstanding, Good, Very Good, Outstanding, Very Good, Good, Outstanding (a) Find the frequency distribution and relative frequency distribution for these data. (Round your relative frequency answers to 3 decimal places.) - RIGHT ANSWER -Outstanding = 14, 0.467 Very Good = 10, 0.333 Good = 5, 0.167 Average = 1, 0.033 Poor = 0, 0.000 HW #4 Consider the following data on distances traveled by people to visit the local amusement park and calculate the relative frequency for the distances over 24 miles. 1. distance: 1-8 miles; frequency: 15 2. distance: 9-16 miles; frequency: 12 3. distance: 17-24 miles; frequency: 7 4. distance: 25-32 miles; frequency: 5 5. distance: 33-40 miles; frequency: 1 a. .150 b. .025 c. .125 d. .375 e. .325 - RIGHT ANSWER -a. .150 HW #4 Consider the following data on distances traveled by people to visit the local amusement park and calculate the relative frequency for the shortest distance. 1. distance: 1-8 miles; frequency: 15 2. distance: 9-16 miles; frequency: 12 3. distance: 17-24 miles; frequency: 7 4. distance: 25-32 miles; frequency: 5 5. distance: 33-40 miles; frequency: 1 a. .300 b. .375 c. .333 d. .150 e. .500 - RIGHT ANSWER -b. .375 HW #4 T/F: A bar chart is a graphic that can be used to depict qualitative data. - RIGHT ANSWER -true HW #4 T/F: The relative frequency is the frequency of a class divided by the total number of measurements. - RIGHT ANSWER -true HW #4 T/F: When data are qualitative, the bars should never be separated by gaps. - RIGHT ANSWER -false HW #4 The following is a partial relative frequency distribution of grades in an introductory statistics course. Find the relative frequency for the B grade. 1. grade - A ;relative freq. - 0.22 2. grade - B ;relative freq. - ? 3. grade - C ;relative freq. - 0.18 4. grade - D ;relative freq. - 0.17 5. grade - F ;relative freq. - 0.06 a. .47 b. .65 c. .27 d. .37 e. .78 - RIGHT ANSWER -d. .37 HW #4 The proportion of measurements in a class is called the ________ of that class. a. cumulative percentage b. leaf c. relative frequency d. frequency - RIGHT ANSWER -c. relative frequency HW #4 Use the Pareto Chart given in the lecture powerpoint to answer this question. _____% of the defects are cause by printing errors. - RIGHT ANSWER -15.6 HW #4 Use the Pareto Chart given in the lecture powerpoint to answer this question. ____% of the defects are caused by printing errors. (Give answer to one decimal place as a percent and not a proportion; Do not include the percent sign in your answer) - RIGHT ANSWER -15.6 HW #4 Use the Pareto Chart given in the lecture powerpoint to answer this question. The cumulative percent of defects due to Crooked Label and Missing Label is ______% - RIGHT ANSWER -58.2 HW #4 Use the Pareto Chart given in the lecture powerpoint to answer this question. What are the "vital few" defect(s) that should be corrected based on the 80/20 Pareto Principle? a. Smudged Label and Other b. Loose Label c. Crooked Label, Printing Error, and Wrinkled Label d. Crooked Label, Missing Label, Printing Error, Loose Label e. Crooked Label - RIGHT ANSWER -d. Crooked Label, Missing Label, Printing Error, Loose Label HW #4 When developing a frequency distribution, the class (group) intervals must be ________. a. small b. integer c. nonoverlapping d. large e. equal - RIGHT ANSWER -c. nonoverlapping HW #4 Which of the following is a type of question used in survey research? a. dichotomous b. All of the other answers are correct. c. multiple-choice d. open-ended - RIGHT ANSWER -b. All of the other answers are correct. HW #4 The Kia Plant needs to determine the cumulative frequency of defects in the production of a car door hinge. Which type of graph should they use to accurately present this information? a. Pie Chart b. Pareto Chart c. Line Graph d. Histogram e. Bar Graph - RIGHT ANSWER -b. Pareto Chart HW #5 A ________ displays the frequency of each class with qualitative data and a ________ displays the frequency of each class with quantitative data. a. scatter plot, bar chart b. bar chart, histogram c. stem-and-leaf, pie chart d. histogram, stem-and-leaf display - RIGHT ANSWER -b. bar chart, histogram HW #5 A plot that allows us to visualize the relationship between two variables is a(n) ________ plot. a. frequency b. dot c. scatter d. ogive - RIGHT ANSWER -c. scatter HW #5 Below we list several variables. Which of these variables are quantitative and which are qualitative? a. The dollar amount on an accounts receivable invoice. b. The net profit for a company in 2017. c. The stock exchange on which a company's stock is traded. d. The national debt of the United States in 2017. e. The advertising medium (radio, television, or print) used to promote a product. - RIGHT ANSWER -a. Quantitative b. Quantitative c. Qualitative d. Quantitative e. Qualitative HW #5 If a histogram has a long left or right tail, the data is described as: a. Misleading b. Approximately Normal c. A story d. All of these e. Skewed - RIGHT ANSWER -e. Skewed HW #5 What should be included on a graph axis when the scale does not start at zero? - RIGHT ANSWER -slashes HW #5 Which of the following correlation coefficients describes the strongest relationship between two quantitative variables? a. 0.85 b. 0.25 c. -0.80 d. 1.29 e. 0.15 - RIGHT ANSWER -a. 0.85 HW #5 A ________ shows the relationship between two quantitative variables. a. scatter plot b. histogram c. bar chart d. pie chart e. pareto chart - RIGHT ANSWER -a. scatter plot HW #5 An example of manipulating a graphical display to distort reality is ________. a. starting the axes at zero b. making the bars in a histogram equal widths c. stretching the axes d. adding an unbiased caption - RIGHT ANSWER -c. stretching the axes HW #5 Given a scatterplot, if one quantitative variable increases as the other quantitative variable increases, the _____ of the correlation coefficient is _______. (one word per blank) - RIGHT ANSWER -direction, positive HW #5 Given a scatterplot, if one quantitative variable increases when the other quantitative variable decreases, the _____ of the correlation coefficient is _______. (one word per blank) - RIGHT ANSWER -direction, negative HW #5 If a dataset's maximum value is 1500 but the graph only goes to 1000, this is an example of: a. Ownership b. Data Ethics c. None of these d. Data Analytics e. Misleading Graphs - RIGHT ANSWER -e. Misleading Graphs HW #5 T/F: A scatter plot is mainly used to identify outliers. - RIGHT ANSWER -False HW #5 T/F: Beginning the vertical scale of a graph at a value different from zero can cause increases to look more dramatic. - RIGHT ANSWER -True HW #5 T/F: When looking at the shape of the distribution using a histogram, a distribution is skewed to the right when the distribution has a long right tail. - RIGHT ANSWER -True HW #5 What is it called when we combine graphs (visuals) with predictive analytics? a. Visual Analytics b. Storytelling c. Graphic Tabulations d. Data Visualization e. None of these - RIGHT ANSWER -a. Visual Analytics HW #5 What is the process of displaying large quantities of data in a meaningful way called? a. Storytelling b. None of these c. Data Visualization d. Visual Analytics e. Big Data - RIGHT ANSWER -c. Data Visualization HW #5 Which of the following are included in the Key Points of Storytelling? a. Eliminate distorted axes b. Always start the frequency axis at zero c. Choose the appropriate graph & tell an accurate story d. Include slashes e. Always include a title and data values - RIGHT ANSWER -c. Choose the appropriate graph & tell an accurate story HW #5 Which of the following correlation coefficient describes the weakest relationship between two quantitative variables? a. -0.800 b. .15 c. 1.29 d. 0.70 e. -0.50 - RIGHT ANSWER -b. 15 HW #5 Which of the following divides quantitative measurements into classes and graphs the frequency, relative frequency, or percentage frequency for each class? a. scatter plot b. dot plot c. histogram d. stem-and-leaf display - RIGHT ANSWER -c. histogram HW #5 Which one of the following graphical tools is used to graph the frequency of employee salaries for Target? a. histogram b. bar chart c. pie chart d. Pareto chart - RIGHT ANSWER -a. histogram HW #6 T/F: Statistical inference is the science of using a sample of measurements to make generalizations about the important aspects of a population of measurements. - RIGHT ANSWER -True HW #6 T/F: Using a nonrandom sample procedure in order to support a desired conclusion is an example of an unethical statistical procedure. - RIGHT ANSWER -True HW #6 The Data Ethics principle that supports datasets can be made available to the public is: a. Privacy b. Openness c. Currency d. Consent e. Ownership - RIGHT ANSWER -b. Openness HW #6 When a company sells your data from a datasourcing method such as clickstream, this is an example of which data ethic principle? a. Ownership b. Openness c. Consent d. Currency e. Privacy - RIGHT ANSWER -d. Currency HW #6 Which of the following is a categorical variable? a. value of company stock b. whether a person has a traffic violation c. bank account balance d. air temperature e. daily sales in a store - RIGHT ANSWER -b. whether a person has a traffic violation HW #6 Which of the following is not an example of unethical statistical practices? a. using graphs to make statistical inferences b. None of the other answers is correct. c. inappropriate interpretation of statistical results d. descriptive measures that mislead the user e. improper sampling - RIGHT ANSWER -a. using graphs to make statistical inferences HW #6 An unusually large or small observation separated from the rest of the data is a(n) ________. a. absolute extreme b. quartile c. outlier d. mode - RIGHT ANSWER -c. outlier HW #6 From the video we watched in class (the link is provided in the powerpoint in module Misleading Graphs), the act of choosing a portion of the axis which leads to telling a misleading story is called: a. Biased Selection b. Openness c. Cherry Picking d. Informed Consent e. Analytics Visualization - RIGHT ANSWER -c. Cherry Picking HW #6 If Amazon wanted to ensure a customers' response to an online survey was confidential and the sampling method was unbiased, which of the following should be implemented? a. Use a means of distribution to ensure there is no identification to any of the participants b. Send an email to customers with only a first or last name in their userid but not both c. Identify each randomly selected customer by a random identification number d. Use clickstream to collect the data e. Make sure those customers who volunteer to reply are coded with random identification number - RIGHT ANSWER -c. Identify each randomly selected customer by a random identification number HW #6 If we are concerned whether the data was collected confidentially or anonymously, this is an example of which data ethic principle? a. Currency b. Consent c. Privacy d. Openness e. Ownership - RIGHT ANSWER -c. Privacy HW #6 The Data Ethics principle that ensures a participant is aware of what data is being collected, the purpose, and how the data will be used is _________. (one word answer) - RIGHT ANSWER -consent HW #6 The question "Do you use third-party cookies" is an example of what would be asked if a person was concerned about: a. All of these b. Openness Data Ethics Principle c. Privacy Storytelling Principle d. Data Visualization Principle e. Privacy Data Ethics Principle - RIGHT ANSWER -e. Privacy Data Ethics Principle HW #8 T/F: An analytic dashboard presents both current and historical trends of a business's key performance indicators. - RIGHT ANSWER -True HW #8 A histogram that has a longer tail extending toward smaller values is ________. a. a scatter plot b. normal c. skewed to the right d. skewed to the left - RIGHT ANSWER -d. skewed to the left HW #8 A relative frequency histogram having a longer tail to the right than to the left is said to be ________. a. skewed to the right b. normal c. a scatter plot d. skewed to the left - RIGHT ANSWER -a. skewed to the right HW #8 A(n) ________ is a graphical presentation of the current status and historical trends of a business's key performance indicators. a. dashboard b. Pareto chart c. frequency distribution d. histogram - RIGHT ANSWER -a. dashboard HW #8 All of the following are measures of central tendency except the ________. a. mean b. mode c. range d. median - RIGHT ANSWER -c. range HW #8 If a population distribution is skewed to the right, then, given a random sample from that population, one would expect that the ________. a. median would be equal to the mean b. median would be greater than the mean c. median would be less than the mean d. mode would be equal to the mean - RIGHT ANSWER -c. median would be less than the mean HW #8 If the mean is greater than the median, then the relative frequency curve is most likely to be ________. a. skewed left b. skewed right c. bimodal d. symmetrical - RIGHT ANSWER -b. skewed right HW #8 If the mean, median, and mode for a given population are all equal and the relative frequency curve has matching tails to the right and left, then we would describe the shape of the distribution of the population as ________. a. skewed to the left b. skewed to the right c. symmetrical d. bimodal - RIGHT ANSWER -c. symmetrical HW #8 In a hearing test, randomly selected subjects estimate the loudness (in decibels) of a sound, and the results are (mean = 70): 68, 67, 70, 71, 68, 75, 68, 62, 80, 73, 68. What is the range? a. 22.40 b. 4.73 c. 6.76 d. 324 e. 18 - RIGHT ANSWER -e. 18 HW #8 In a statistics class, 10 scores were randomly selected with the following results (mean = 71.5): 74, 73, 77, 77, 71, 68, 65, 77, 67, 66. What is the range? a. 144.00 b. 4.77 c. 516.20 d. 12.00 e. 22.72 - RIGHT ANSWER -d. 12.00 HW #8 In a statistics class, the following 10 scores were randomly selected: 74, 73, 77, 77, 71, 68, 65, 77, 67, 66. What is the mean? a. 77.0 b. 73.0 c. 71.5 d. 71.0 e. 72.0 - RIGHT ANSWER -c. 71.5 HW #8 In a statistics class, the following 10 scores were randomly selected: 74, 73, 77, 77, 71, 68, 65, 77, 67, 66. What is the median? a. 77.0 b. 73.0 c. 71.0 d. 71.5 e. 72.0 - RIGHT ANSWER -e. 72.0 HW #8 In a statistics class, the following 10 scores were randomly selected: 74, 73, 77, 77, 71, 68, 65, 77, 67, 66. What is the mode? a. 73.0 b. 71.0 c. 72.0 d. 71.5 e. 77.0 - RIGHT ANSWER -e. 77.0 HW #8 Lauren is a college sophomore majoring in business. This semester Lauren is taking courses in accounting, economics, management information systems, public speaking, and statistics. The sizes of these classes are, respectively, 360, 55, 70, 45, and 35. (a) Find the mean and the median of the class sizes. (b) What is a better measure of Lauren's "typical class size"—the mean or the median? - RIGHT ANSWER -(a) 113, 55 (b) median HW #8 T/F: Range is a better measure of variation than standard deviation. - RIGHT ANSWER -False HW #8 T/F: The median is said to be resistant to extreme values. - RIGHT ANSWER -True HW #8 T/F: The median is the measure of central tendency that divides a population or sample into four equal parts. - RIGHT ANSWER -False HW #8 T/F: The median is the value below which and above which approximately 50 percent of the measurements lie. - RIGHT ANSWER -True HW #8 T/F: The mode is the measurement in a sample or population that occurs most frequently. - RIGHT ANSWER -True HW #8 T/F: The population mean is the average of the population measurements. - RIGHT ANSWER -True HW #8 T/F: The range of the measurement is the largest measurement plus the smallest measurement. - RIGHT ANSWER -False HW #8 The ________ is the positive square root of the sample variance. a. population standard deviation b. range c. median d. sample standard deviation e. sample mean - RIGHT ANSWER -d. sample standard deviation HW #8 Which of the following is influenced the least by the occurrence of extreme values in a sample? a. geometric mean b. mean c. median d. weighted mean - RIGHT ANSWER -c. median HW #8 A graphical portrayal of a quantitative data set that divides the data into classes and gives the frequency of each class is a(n) ________. a. histogram b. dot plot c. bar chart d. ogive plot e. Pareto chart - RIGHT ANSWER -a. histogram HW #9 A measurement located outside the upper limits of a box-and-whiskers display is ________. a. an outlier b. always the largest value in the data set c. always in the first quartile d. within the lower limits - RIGHT ANSWER -a. an outlier HW #9 A survey of the top 10 employees in a major Midwest city found workers spent an average of 413 minutes per day on a job with standard deviation = 26.8 minutes. If the time spent on the job is approximately normal, what are the times within which approximately 68% of all workers fall? a. [386.2,439.8] b. [372.8,453.2] c. [332.6,493.4] d. [359.4,466.6] e. [394.8,431.2] - RIGHT ANSWER -a. [386.2,439.8] HW #9 Another name for the 50th percentile is the ________. a. mode b. median c. first quartile d. mean e. third quartile - RIGHT ANSWER -b. median HW #9 Find the z-score for an IQ test score of 118 when the mean is 100 and the standard deviation is 15. a. 1.2 b. 18.0 c. −1.03 d. 1.0 e. −1.2 - RIGHT ANSWER -a. 1.2 HW #9 Find the z-score for an IQ test score of 125 when the mean is 100 and the standard deviation is 15. a. −1.1 b. 1.1 c. −1.67 d. 1.67 e. 25 - RIGHT ANSWER -d. 1.67 HW #9 Find the z-score for an IQ test score of 142 when the mean is 100 and the standard deviation is 15. a. 1.27 b. 18.78 c. 42 d. 2.8 e. −2.8 - RIGHT ANSWER -d. 2.8 HW #9 If the median of a data set is 760, the third quartile is 950, and the first quartile is 650, what is the interquartile range? a. 190 b. 300 c. 150 d. 910 e. 110 - RIGHT ANSWER -b. 300 HW #9 In a statistics class, 10 scores were randomly selected with the following results (mean = 71.5): 74, 73, 77, 77, 71, 68, 65, 77, 67, 66. What is the range? a. 12.00 b. 516.20 c. 4.77 d. 144.00 e. 22.72 - RIGHT ANSWER -a. 12.00 HW #9 In a statistics class, 10 scores were randomly selected with the following results: 74, 73, 77, 77, 71, 68, 65, 77, 67, 66. What are the lower and upper limits of a box-and-whiskers display of this data? a. 57, 87 b. 37, 107 c. 52, 92 d. 47, 97 e. 67, 77 - RIGHT ANSWER -c. 52, 92 HW #9 In a statistics class, 10 scores were randomly selected with the following results: 74, 73, 77, 77, 71, 68, 65, 77, 67, 66. What is the IQR? a. 5.00 b. 10 c. 12.00 d. 5.25 e. 11.00 - RIGHT ANSWER -b. 10 HW #9 In a statistics class, 10 scores were randomly selected with the following results: 74, 73, 77, 77, 71, 68, 65, 77, 67, 66. What is the third quartile? a. 73.85 b. 77.0 c. 66.75 d. 67.3 e. 65.9 - RIGHT ANSWER -b. 77.0 HW #9 In a statistics class, 10 scores were randomly selected with the following results: 74, 73, 77, 77, 71, 68, 65, 77, 67, 66.What is the 65th percentile? a. 65.5 b. 66.75 c. 74.0 d. 67.3 e. 77.0 - RIGHT ANSWER -c. 74.0 HW #9 In a statistics class, 10 scores were randomly selected, with the following results: 74, 73, 77, 77, 71, 68, 65, 77, 67, 66. What is the 10th percentile? a. 66.75 b. 77.0 c. 67.3 d. 65.5 - RIGHT ANSWER -d. 65.5 HW #9 The average lateness for one of the top airline companies is 10 minutes. The variance of the lateness measure is calculated as 9. An airplane arrived 13 minutes after the stated arrival time. Calculate the z-score for the lateness of this particular airplane. a. .58 b. 1.00 c. .33 d. 1.33 e. .44 - RIGHT ANSWER -b. 1.00 HW #9 The company financial officer was interested in the average cost of PCs that had been purchased in the past six months. She took a random sample of the price of 10 computers, with the following results. $3,250, $1,127, $2,995, $3,250, $3,445, $3,449, $1,482, $6,120, $3,009, $4,000 What are the lower and upper limits of a box-and-whiskers display of this data? a. 1633, 2087 b. 2768, 3676 c. 2087, 4357 d. 2314, 4130 - RIGHT ANSWER -d. 2314, 4130 HW #9 The company financial officer was interested in the average cost of PCs that had been purchased in the past six months. She took a random sample of the price of 10 computers, with the following results. $3,250, $1,127, $2,995, $3,250, $3,445, $3,449, $1,482, $6,120, $3,009, $4,000 What is the third quartile? a. $3,449.00 b. $4,212.00 c. $3,415.75 d. $2,617.00 e. $1,446.50 - RIGHT ANSWER -a. $3,449.00 HW #9 Which percentile describes the third quartile, Q3? a. 75th b. 25th c. 100th d. 50th - RIGHT ANSWER -a. 75th HW #9 A normal population has 99.73 percent of the population measurements within ________ standard deviation(s) of the mean. a. 2 b. 4 c. 1 d. 3 - RIGHT ANSWER -d. 3 HW #9 Personnel managers usually want to know where a job applicant ranked in his or her graduating class. With a grade point average of 3.83, Michelle Robinson graduated above the 93rd percentile of her graduating class. What is the percentile rank of a student whose GPA was the median GPA? a. 10th b. 25th c. 75th d. 50th e. 93rd - RIGHT ANSWER -d. 50th HW #9 Suppose that 20 randomly selected customers give the following satisfaction ratings (on a scale of 1 to 10) for a DVD recorder. 1 3 5 5 7 8 8 8 8 8 8 9 9 9 9 Find the first quartile, the median, and the third quartile for these data. (Round your answers to 1 decimal place.) - RIGHT ANSWER -- Q1 = 7.5 - Median = 8 - Q3 = 9 HW #9 The company financial officer was interested in the average cost of PCs that had been purchased in the past six months. She took a random sample of the price of 10 computers, with the following results. $3,250, $1,127, $2,995, $3,250, $3,445, $3,449, $1,482, $6,120, $3,009, $4,000 What is the first quartile? a. $3,587.00 b. $4,212.00 c. $3,415.75 d. $2,995.00 e. $1,446.50 - RIGHT ANSWER -d. $2,995.00