Question: On the Internet, look up two influential

> A process has specification limits of LSL = 540 and USL = 550. The process standard deviaton is σ = 1.25. Find the Cp and Cpk capability indexes if (a) the process mean is 545; (b) the process mean is 543.

> Define three quality metrics that might be used to describe quality and performance for the following services: (a) your cellular phone service (e.g., Verizon); (b) your Internet service provider (e.g., AOL); (c) your dry cleaning and laundry service; (d

> Are the X and Y data well-conditioned? If not, make any transformations that may be necessary and explain. DATA SET A Mileage and Other Characteristics of Randomly Selected Vehicles (n = 73, k = 4) O Mileage Obs Vehicle CityMPG Length Widt

> Define three possible quality metrics (not necessarily the ones actually used) to describe and monitor: (a) your performance in your college classes; (b) effectiveness of the professors in your college classes; (c) your effectiveness in managing your per

> Explain each chart’s purpose and the parameters that must be known or estimated to establish its control limits. a.
chart b. R chart c. p chart d. I chart

> Pick one Excel data set (A through F) and investigate whether the data could have come from a normal population using α = .01. Use any test you wish, including a histogram, or MegaStat’s Descriptive Statistics > Normal

> (a) Make a scatter plot of the data. What does it suggest about the correlation between X and Y? (b) Use Excel, MegaStat, or MINITAB to calculate the correlation coefficient. (c) Use Excel or Appendix D to find t.025 for a two-tailed test at Î&plu

> The table below shows the number of ATM customer arrivals per minute in 60 randomly chosen minutes. Research question: At α = .025, can you reject the hypothesis that the number of arrivals per minute follows a Poisson process? 0 0 1 3

> In the World Cup tournaments between 1990 and 2002, there were 232 games with the distribution of goals shown in this worksheet. Research question: At α = .025, can you reject the hypothesis that goals per game follow a Poisson process? You

> A student rolled a supposedly fair die 60 times, resulting in the distribution of dots shown. Research question: At α = .10, can you reject the hypothesis that the die is fair? Number of Dots 1 2 3 5 6. Total Frequency 7 14 13 7 10 60

> In a four-digit lottery, each of the four digits is supposed to have the same probability of occurrence. The table shows the frequency of occurrence of each digit for 89 consecutive daily four digit drawings. Research question: At α = .01, can you reject

> Oxnard Kortholt, Ltd., employs 50 workers. Research question: At α = .05, do Oxnard employees differ significantly from the national percent distribution? Oxnard Employees Frequency National Health Care Visits Percentage No visits 16.5

> Prof. Green’s multiple-choice exam had 50 questions with the distribution of correct answers shown below. Research question: At α = .05, can you reject the hypothesis that Green’s exam answers came from a uniform population? Correct Answer …………………………………

> Are these cross-sectional data or time-series data? What is the unit of observation (e.g., firm, individual, year)? DATA SET A Mileage and Other Characteristics of Randomly Selected Vehicles (n = 73, k = 4) O Mileage Obs Vehicle CityMPG Le

> Make a scatter plot of Y against X. Discuss what it tells you. Midterm and Final Exam Scores for Business Statistics Students Fall Semester 2011 (n = 58 students) Midterm Exam Score ………â

> The actual distribution of car colors for 2006 model car buyers is shown below. Based on the sample of 200 car buyers for 2012 model vehicles, use the multinomial chi-square GOF test at α = .05 to test whether car buyers’

> A survey of 189 statistics students asked the age of car usually driven and the student’s political orientation. The car age was a numerical variable, which was converted into ordinal categories. Research question: At α =

> A survey of randomly chosen new students at a certain university revealed the data below concerning the main reason for choosing this university instead of another. Research question: At α = .01, is the main reason for choosing the univers

> Can people really identify their favorite brand of cola? Volunteers tasted Coke, Pepsi, Diet Coke, and Diet Pepsi, with the results shown below. Research question: At α = .05, is the correctness of the prediction different for regular cola

> Driving without a seat belt is not risky. I’ve done it for 25 years without an accident.” This best illustrates which fallacy? a. Unconscious bias. b. Conclusion from a small sample. c. Post hoc reasoning.

> Researchers found a correlation coefficient of r = .50 on personality measures for identical twins. A reporter interpreted this to mean that “the environment orchestrated one-half of their personality differences.” Do you agree with this interpretation?

> A researcher used stepwise regression to create regression models to predict CarTheft (thefts per 1,000) using four predictors: Income (per capita income), Unem (unemployment percent), Pupil/ Tea (pupil-to-teacher ratio), and Divorce (divorces per 1,000

> For a multiple regression, which statement is true? Why not the others? a. Evans’ Rule suggests at least 10 observations for each predictor. b. The tcalc in a test for significance of a binary predictor can have only two values. c. Occam’s Razor says we

> Make a fishbone chart (cause-and-effect diagram) for the reasons an airline flight might be late to arrive. Use as many branches as necessary. Which factors are most important? Which are most easily controlled? Flight Is Late Arriving at Destination

> Make a fishbone chart (cause-and-effect diagram) for the reasons your end-of-month checkbook balance may not match your bank statement. Use as many branches as necessary. Which factors are most important? Which are most easily controlled? Checkbook

> A forecasting model is fitted to sales data over 24 months. Forecasting errors are tabulated to reveal whether the model provides an overestimate (1) or an underestimate (2) for each month’s sales. The results are - - + + + - + - - + + - - - - - - + + +

> Make a fishbone chart (cause-and-effect diagram) like the following for the reasons you have ever been (or could be) late to class. Use as many branches as necessary. Which factors are most important? Which are most easily controlled? Late Arrival t

> Why are p charts widely used in service applications like health care?

> Which is not an ethical obligation of a statistician? Explain. a. To know and follow accepted procedures. b. To ensure data integrity and accurate calculations. c. To support client wishes in drawing conclusions from the data.

> To choose a sample of 12 students from a statistics class of 36 students, which type of sample (simple random, systematic, cluster, convenience), is each of these? a. Picking every student who was wearing blue that day. b. Using Excel’s =RANDBETWEEN (1,

> Tell if each variable is continuous or discrete. a. Tonnage carried by an oil tanker at sea. b. Wind velocity at 7 o’clock this morning. c. Number of text messages you received yesterday.

> Which statement is incorrect? Explain. a. The triangular always has a single mode. b. The mean of the triangular is (a + b + c)/3. c. The triangular cannot be skewed left or right.

> Which is not a characteristic of using a log scale to display time series data? Explain. a. A log scale helps if we are comparing changes in two time series of dissimilar magnitude. b. General business audiences find it easier to interpret a log scale.

> Give the type of measurement (nominal, ordinal, interval, ratio) for each variable. a. Length of time required for a randomly chosen vehicle to cross a toll bridge. b. Student’s ranking of five cell phone service providers. c. The type of charge card us

> Tell if each statement is true or false for a simple regression. If false, explain. a. If the standard error is syx = 3,207, then a residual ei = 4,327 would be an outlier. b. In a regression with n = 50, then a leverage statistic hi = .10 indicates unu

> Describe two quality improvement tools unique to the service industry.

> In a study of stock prices from 1970 to 1994, the correlation between Nasdaq closing prices on successive days (i.e., with a 1-day lag) was r = .13 with a t statistic of 5.47. Interpret this result. (See David Nawrocki, “The Problems with Monte Carlo Sim

> Why is the quality improvement process never-ending? Identify the steps of one improvement cycle identified in the textbook.

> (a) What determines sampling frequency? (b) Why are variable samples often small? (c) Why are attribute samples often large?

> What is the difference between an attribute control chart and a variable control chart?

> Which statement is true for a normal distribution? Why not the others? a. The shape of the PDF is always symmetric regardless of μ and σ. b. The shape of the CDF resembles a bell-shaped curve. c. When no tables are available, areas may be found by a sim

> Name the survey instrument used to measure service quality. What are the five service quality dimensions?

> Which statement is false? Explain. a. In the hypergeometric distribution, sampling is done without replacement. b. The mean of the uniform distribution is always (a + b)/2. c. We use the geometric distribution to find probabilities of arrivals per unit o

> Identify three common quality improvement programs and give their acronyms.

> Explain the difference between SQC and SPC.

> Which data type (categorical, numerical) is each of the following? a. Your current credit card balance. b. Your college major. c. Your car’s odometer mileage reading today.

> Which statement is correct for a simple regression? Why not the others? a. A 95% confidence interval (CI) for the mean of Y is wider than the 95% CI for the predicted Y. b. A confidence interval for the predicted Y is widest when X =
. c. The t test for

> The price of a particular stock over a period of 60 days rises (1) or declines (2) in the following pattern. Research question: At α = .05, is the pattern random? + + - - - + + + + + + + - - - - + + - + - + - + - - - - + + + + - + + + + - + + + - + - + -

> Explain the role of statisticians in quality improvement.

> Which statement is true? Why not the others? a. The Poisson distribution has two parameters. b. The binomial distribution assumes dependent random trials. c. The uniform distribution has two parameters.

> Can zero variation be achieved? Explain.

> Explain the difference between common cause variation and special cause variation.

> Match each statement to the correct property of an estimator (unbiased, consistent, efficient): a. The estimator “collapses” on the true parameter as n increases. b. The estimator has a relatively small variance. c. The expected value of the estimator i

> Which type of probability (empirical, classical, subjective) is each of the following? a. On a given Friday, the probability that Flight 277 to Chicago is on time is 23.7%. b. Your chance of going to Disney World next year is 10%. c. The chance of rolli

> Define a measurable aspect of quality for (a) the car dealership where you bought your car, (b) the bank or credit union where you usually make personal transactions, and (c) the movie theater where you usually go.

> Look up two of Deming’s 14 points on the Internet and explain their meaning.

> Explain the relationship between productivity and quality from a modern perspective. How does this differ from the past perspective?

> Thirty-four customers at Starbucks either ordered coffee (C) or did not order coffee (X). Research question: At α = .05, is the sequence random? C X C X C C C C X X X X C X C X C X C C C X C X C C X C X X X C C X

> Which statement is not correct concerning a p-value? Explain. a. Ceteris paribus, a larger p-value makes it more likely that H0 will be rejected. b. The p-value shows the risk of Type I error if we reject H0 when H0 is true. c. In making a decision, we

> List four rules for detecting abnormal (special cause) observations in a control chart.

> (a) To construct control limits for an
chart, name three ways to estimate σ empirically. (b) Why is the
method often used? (c) Why is the s method the default in MINITAB?

> Samples are shown of volatility (coefficient of variation) for sector stocks over a certain period of time. (a). At α = .05, is there a difference in median volatility in these four portfolios? Use Mega- Stat, MINITAB, or a similar compu

> An experimental bumper was designed to reduce damage in low-speed collisions. This bumper was installed on an experimental group of vans in a large fleet, but not on a control group. At the end of a trial period, there were 12 repair incidents (a “repair

> Bob and Tom are “paper investors.” They each “buy” stocks they think will rise in value and “hold” them for a year. At the end of the year, they c

> Final exam scores for a sample of 20 students in a managerial accounting class are shown. (a). At α = .05, is there a difference in the population median scores on the two exams? Make an Excel worksheet for your Wilcoxon signed-rank test

> A sample of 28 student scores on the chemistry midterm exam is shown. (a). At α = .10, does the population median differ from 50? Make a worksheet in Excel for your calculations. (b). Make a histogram of the data. Would you be justified

> A baseball player was at bat 33 times during preseason exhibition games. His pattern of hits (H) and nonhits (N) is shown (a nonhit is a walk or a strikeout). Research question: At = 5 .01, is the pattern of hits random? N N N H N H N N H N N H H N N N N

> On a professional certifying exam, there are 25 true-false questions. The correct answers are T F T T F F F T T F T F T T T F F T T F F T T F T. Research question: At α = .05, is the T/F pattern random?

> Which data would be most suitable for a pie chart? Why not the others? a. Presidential vote in the last election by party (Democratic, Republican, Other). b. Retail prices of six major brands of color laser printers. c. Labor cost per vehicle for 10 maj

> Using α = .10, perform a runs test for randomness on the sample data (n = 24). X O X X X X O O O O X O O O X O O O X O O X X O

> Weights of 12 randomly chosen Sonora Bars (a type of candy) from assembly line 1 had a mean weight of 56.25 grams (g) with a standard deviation of 0.65 g, while the weights of 12 randomly chosen Sonora Bars from assembly line 2 had a mean weight of 56.75

> Rates of return on 24 mutual funds are shown. (a) Convert the data to ranks. Check the column sums. (b) Calculate Spearman’s rank correlation coefficient. Show your calculations. (c) At α = .01 can you reject the hypothesi

> Profits of 20 consumer food companies are shown. (a) Convert the data to ranks. Check the column sums. (b) Calculate Spearman’s rank correlation coefficient. Show your calculations. (c) At α = .01 can you reject the hypoth

> JavaMax is a neighborhood take-out coffee shop that offers three sizes. Yesterday’s sales are shown. Use MegaStat or another software package to perform a Friedman test to see whether the median sales of coffee sizes differ at Î&p

> Consumers are asked to rate the attractiveness of four potential dashboard surface textures on an interval scale (1 5 least attractive, 10 5 most attractive). Use MegaStat or another software package to perform a Friedman test to see whether the median r

> The results shown below are mean productivity measurements (average number of assemblies completed per hour) for a random sample of workers at each of three work stations. (a). At α = .05, is there a difference in median productivity? Us

> Using α = .05, perform a runs test for randomness on the sample data (n = 27). A A B B A A B B A B A A B B B A A B B B B A A B A B B

> One-year sales volume of four similar 20-oz. beverages on a college campus is shown. Beverage ………………………………………………………. Sales (Cases) Frappuccino Coffee ………………………………………………………... 18 Frappuccino Mocha ………………………………………………………… 23 Frappuccino Vanilla …………………………

> Advertisers need to know which age groups are likely to see their ads. Purchasers of 120 copies of Cosmopolitan are shown by age group. Purchaser Age ………………………………………………. Units Sold 18–24 ……………………………………………….………………………. 38 25–34 ……………………………………………….…………………

> Use MegaStat or MINITAB to identify observations with high leverage. Midterm and Final Exam Scores for Business Statistics Students Fall Semester 2011 (n = 58 students) Midterm Exam Score ………&

> Market research has shown that Americans will continue to eat out even in a depressed economy. A market analysis during the most recent recession showed the following distribution of visits to the various types of restaurants: A new survey of 250 Ameri

> U.S. market share for smartphones with larger screens is increasing. As of the first quarter of 2011, smartphones with screens 4 inches or larger had captured 24 percent of the smartphone market. The market for smartphones with screens between 3.5 and 3.

> Last month, 85 percent of the visitors to the Sonora Candy Factory made a purchase in the on-site candy shop after taking the factory tour. This month, a random sample of 500 such visitors showed that 435 purchased candy after the tour. The manager said,

> Marketing researchers sent an advance e-mail notice announcing an upcoming Internet survey and describing the purpose of their research. Half the target customers received the prenotification, followed by the survey. The other half received only the surv

> Is HDTV ownership related to quantity of purchases of othe r electronics? A Best Buy retail outlet collected the following data for a random sample of its recent customers. Research question: At α = .10, is the frequency of in-store purchas

> Students applying for admission to an MBA program must submit scores from the GMAT test, which includes a verbal and a quantitative component. Shown here are raw scores for 100 randomly chosen MBA applicants at a Midwestern, public, AACSB-accredited busi

> Teenagers make up a large percentage of the market for clothing. Below are data on running shoe ownership in four world regions (excluding China). Research question: At α = .01, does this sample show that running shoe ownership depends on w

> Use MINITAB’s Stat > Basic Statistics > Normality Test or other software to obtain a probability plot for the exam score data (see Exercise 15.15). Interpret the probability plot and Anderson-Darling statistic. Exercise 15.15: E

> One Friday night, there were 42 carry-out orders at Ashoka Curry Express. (a). Estimate the mean and standard deviation from the sample. (b). Assuming that the data are from a normal distribution, define bins by using method 3 (equal expected frequen

> Exam scores of 40 students in a statistics class are shown. (a). Estimate the mean and standard deviation from the sample. (b). Assuming that the data are from a normal distribution, define bins by using method 3 (equal expected frequencies). Use 8 b

> Use MegaStat or MINITAB to generate 95 percent confidence and prediction intervals for various X-values. Midterm and Final Exam Scores for Business Statistics Students Fall Semester 2011 (n = 58 students) Midterm Exam Score …â

> At a local supermarket receiving dock, the number of truck arrivals per day is recorded for 100 days. (a). Estimate the mean from the sample. (b). Calculate the expected frequencies assuming a Poisson distribution. Show your calculations in a spreads

> During the 1973–74 hockey season, the Boston Bruins played 39 home games and scored 193 points, as shown below. (a). Estimate the mean from the sample. (b). Calculate the expected frequencies assuming a Poisson distribution. Show yo

> Excel was asked to generate 50 Poisson random numbers with mean λ = 5. X ……………………………………………………………….. Frequency 0 ……………………………………………………………………………….. 1 1 ……………………………………………………………………………….. 1 2 ……………………………………………………………………………….. 4 3 ……………………………………………………………………………

> Which statement is correct? Why not the others? a. The level of significance α is the probability of committing Type I error. b. As the sample size increases, critical values of t.05 increase, gradually approaching z.05. c. When σ is unknown, it is conse

> Ages of 56 attendees of a recent Hunger Games movie are shown. (a). Form seven age classes (10 to 20, 20 to 30, etc.). Tabulate the frequency of attendees in each class. (b). Calculate expected frequencies for each class. (c). Perform a chi-square G

> In a three-digit lottery, each of the three digits is supposed to have the same probability of occurrence (counting initial blanks as zeros, e.g., 32 is treated as 032). The table shows the frequency of occurrence of each digit for 90 consecutive daily t

> A random sample of California residents who had recently visited a car dealership were asked which type of vehicle they were most likely to purchase, with the results shown. Research question: At α = .10, is the choice of vehicle type indep

> (a) Use MegaStat or MINITAB to deseasonalize the monthly Corvette sales data and fit a trend. Interpret the results. (b) Use MegaStat or MINITAB to perform a regression using seasonal binaries. Interpret the results. (c) Use the regression equation to ma

> (a) Use MegaStat or MINITAB to deseasonalize the quarterly data on PepsiCo’s revenues and fit a trend. Interpret the results. (b) Use MegaStat or MINITAB to perform a regression using seasonal binaries. Interpret the results. (c) Use th