The operations of seafood restaurant chains such as Red Lobster are sensitive to changes in the price of seafood. Quantity data for a regional seafood chain coupled with price data are in the following table (Statista website).
a. Compute a price relative for each type of seafood.
b. Compute a weighted aggregate price index for the regional seafood chain. Comment on the change in seafood expense over the 16-year period.
> The U.S. Bureau of Labor Statistics reports that 11.3% of U.S. workers belonged to unions in 2013. Suppose a sample of 400 U.S. workers is collected in 2018 to determine whether union efforts to organize have increased union membership. a. Formulate the
> Consider the following hypothesis test: H0: p ≥ .75 Ha: p < .75 A sample of 300 items was selected. Compute the p-value and state your conclusion for each of the following sample results. Use α = .05. a. p̅ = .68 c. p̅ = .70 b. p̅ = .72 d. p̅ = .77
> Consider the following hypothesis test: H0: p = .20 Ha: p ≠ .20 A sample of 400 provided a sample proportion p = .175. a. Compute the value of the test statistic. b. What is the p-value? c. At α = .05, what is your conclusion? d. What is the rejection ru
> Joan’s Nursery specializes in custom-designed landscaping for residential areas. The estimated labor cost associated with a particular landscaping proposal is based on the number of plantings of trees, shrubs, and so on to be used for t
> The mean cost of a meal for two in a mid-range restaurant in Tokyo is $40 (Numbeo.com website). How do prices for comparable meals in Hong Kong compare? The file HongKongMeals contains the costs for a sample of 42 recent meals for two in Hong Kong mid-ra
> The Onsure.com website reports that the mean annual premium for automobile insurance in the United States was $1503 in March 2014. Being from Pennsylvania at that time, you believed automobile insurance was cheaper there and decided to develop statistica
> According to the National Automobile Dealers Association, the mean price for used cars is $10,192. A manager of a Kansas City used car dealership reviewed a sample of 50 recent used car sales at the dealership in an attempt to determine whether the popul
> The United States ranks ninth in the world in per capita chocolate consumption; Forbes reports that the average American eats 9.5 pounds of chocolate annually. Suppose you are curious whether chocolate consumption is higher in Hershey, Pennsylvania, the
> The time married men with children spend on child care averages 6.4 hours per week. You belong to a professional group on family practices that would like to do its own study to determine if the time married men in your area spend on child care per week
> A production line operation is designed to fill cartons with laundry detergent to a mean weight of 32 ounces. A sample of cartons is periodically selected and weighed to determine whether underfilling or overfilling is occurring. If the sample data lead
> On its municipal website, the city of Tulsa states that the rate it charges per 5 CCF of residential water is $21.62. How do the residential water rates of other U.S. public utilities compare to Tulsa's rate? The file ResidentialWater contains the rate p
> A shareholders’ group, in lodging a protest, claimed that the mean tenure for a chief executive office (CEO) was at least nine years. A survey of companies reported in The Wall Street Journal found a sample mean tenure of x̅ = 7.27 years for CEOs with a
> According to the Vivino website, the mean price for a bottle of red wine that scores 4.0 or higher on the Vivino Rating System is $32.48. A New England–based lifestyle magazine wants to determine if red wines of the same quality are less expensive in Pro
> Consider the following hypothesis test: H0: µ = 100 Ha: µ ≠ 100 A sample of 65 is used. Identify the p-value and state your conclusion for each of the following sample results. Use α = .05. a. x̅ = 103 and s = 11.5 b. x̅ = 96.5 and s = 11.0 c. x̅ = 102 a
> Consider the following hypothesis test: H0: µ ≥ 45 Ha: µ < 45 A sample of 36 is used. Identify the p-value and state your conclusion for each of the following sample results. Use α = .01. a. x̅ = 44 and s = 5.2 b. x̅ = 43 and s = 4.6 c. x̅ = 46 and s = 5
> Older people often have a hard time finding work. AARP reported on the number of weeks it takes a worker aged 55 plus to find a job. The data on number of weeks spent searching for a job contained in the file JobSearch are consistent with the AARP findin
> Consider the following hypothesis test: H0: µ = 18 Ha: µ ≠ 18 A sample of 48 provided a sample mean x = 17 and a sample standard deviation σ = 4.5. a. Compute the value of the test statistic. b. Use the t distribution table (Table 2 in Appendix B) to com
> Consider the following hypothesis test: H0: µ ≤ 12 Ha: µ > 12 A sample of 25 provided a sample mean x = 14 and a sample standard deviation σ = 4.32. a. Compute the value of the test statistic. b. Use the t distribution table (Table 2 in Appendix B) to co
> CCN and ActMedia provided a television channel targeted to individuals waiting in supermarket checkout lines. The channel showed news, short features, and advertisements. The length of the program was based on the assumption that the population mean time
> Fowle Marketing Research, Inc., bases charges to a client on the assumption that telephone surveys can be completed in a mean time of 15 minutes or less. If a longer mean survey time is necessary, a premium rate is charged. A sample of 35 surveys provide
> Annual expenditure for prescription drugs was $838 per person in the Northeast of the country. A sample of 60 individuals in the Midwest showed a per person annual expenditure for prescription drugs of $745. Use a population standard deviation of $300 to
> For a t distribution with 16 degrees of freedom, find the area, or probability, in each region. a. To the right of 2.120 b. To the left of 1.337 c. To the left of −1.746 d. To the right of 2.583 e. Between −2.120 and 2.120 f. Between −1.746 and 1.746
> Costs are rising for all kinds of medical care. The mean monthly rent at assisted-living facilities was reported to have increased 17% over the last five years to $3486. Assume this cost estimate is based on a sample of 120 facilities and, from past stud
> The mean cost to repair the smoke and fire damage that results from home fires of all causes is $11,389 (HomeAdvisor). How does the damage that results from home fires caused by careless use of tobacco compare? The file TobaccoFires provides the cost to
> Studies show that massage therapy has a variety of health benefits and it is not too expensive. A sample of 10 typical one-hour massage therapy sessions showed an average charge of $59. The population standard deviation for a one-hour session is σ = $5.5
> Money reports that the average annual cost of the first year of owning and caring for a large dog in 2017 is $1448. The Irish Red and White Setter Association of America has requested a study to estimate the annual first-year cost for owners of this bree
> In an attempt to assess total daily travel taxes in various cities, the Global Business Travel Association conducted a study of daily travel taxes on lodging, rental car, and meals. The data contained in the file TravelTax are consistent with the finding
> Data were collected on the amount spent by 64 customers for lunch at a major Houston restaurant. These data are contained in the file Houston. Based upon past studies the population standard deviation is known with σ = $6. a. At 99% confidence, what is t
> The manager of an automobile dealership is considering a new bonus plan designed to increase sales volume. Currently, the mean sales volume is 14 automobiles per month. The manager wants to conduct a research study to see whether the new bonus plan incre
> Because of high production-changeover time and costs, a director of manufacturing must convince management that a proposed manufacturing method reduces costs before the new method can be implemented. The current production method operates with a mean cos
> A simple random sample of 60 items resulted in a sample mean of 80. The population standard deviation is σ = 15. a. Compute the 95% confidence interval for the population mean. b. Assume that the same sample mean was obtained from a sample of 120 items
> A simple random sample of 50 items from a population with σ = 6 resulted in a sample mean of 32. a. Provide a 90% confidence interval for the population mean. b. Provide a 95% confidence interval for the population mean. c. Provide a 99% confidence in
> A simple random sample of 40 items resulted in a sample mean of 25. The population standard deviation is σ = 5. a. What is the standard error of the mean, σx? b. At 95% confidence, what is the margin of error?
> An investor wants to select one of seven mutual funds for the coming year. Data showing the percentage annual return for each fund during five typical one-year periods are shown here. The assumption is that one of these five-year periods will occur again
> Many factors influence the retail price of gasoline. The following table shows the average retail price for a gallon of regular grade gasoline for each year from 2014 through 2017 (U.S. Energy Information Administration website). Year Average …………………………
> Samples of size 5 provided the following 20 sample means for a production process that is believed to be in control. a. Based on these data, what is an estimate of the mean when the process is in control? b. Assume that the process standard deviation i
> A manufacturer produces lots of a canned food product. Let p denote the proportion of the lots that do not meet the product quality specifications. An η = 25, c = 0 acceptance sampling plan will be used. a. Compute points on the operating characteristic
> An acceptance sampling plan with n = 15 and c = 1 has been designed with a producer’s risk of .075. a. Was the value of p0 .01, .02, .03, .04, or .05? What does this value mean? b. What is the consumer’s risk associated with this plan if p1 is .25?
> An n = 10, c = 2 acceptance sampling plan is being considered; assume that p0 = .05 and p1 = .20. a. Compute both producer’s and consumer’s risk for this acceptance sampling plan. b. Would the producer, the consumer, or both be unhappy with the proposed
> According to the IRS, taxpayers calling the IRS in 2017 waited 13 minutes on average for an IRS telephone assister to answer. Do callers who use the IRS help line early in the day have a shorter wait? Suppose a sample of 50 callers who placed their calls
> Managers of 1200 different retail outlets make twice-a-month restocking orders from a central warehouse. Past experience shows that 4% of the orders result in one or more errors such as wrong item shipped, wrong quantity shipped, and item requested but n
> An insurance company samples claim forms for errors created by its employees as well as the amount of time it takes to process a claim. a. When the process is in control, the proportion of claims with an error is .033. A p chart has LCL = 0 and UCL = .06
> The following were collected for the Master Blend Coffee production process. The data show the filling weights based on samples of 3-pound cans of coffee. Use these data to construct the xÌ… and R charts. What conclusions can be made about th
> The following are quality control data for a manufacturing process at Kensport Chemical Company. The data show the temperature in degrees centigrade at five points in time during a manufacturing cycle. The company is interested in using control charts to
> Twenty-five samples of size 5 resulted in x̅ = 5.42 and R̅ = 2.0. Compute control limits for the x̅ and R charts, and estimate the standard deviation of the process.
> Product filling weights are normally distributed with a mean of 350 grams and a standard deviation of 15 grams. a. Develop the control limits for the x chart for samples of size 10, 20, and 30. b. What happens to the control limits as the sample size is
> Williams Sonoma is a consumer retail company that sells kitchenware. Williams Sonoma has reported the quantity and product value information for three different glass tumblers in two different years in the table that follows. Compute a weighted aggregate
> The closing price of Walmart stock at the end of its fiscal year (end of January) for five years is given in the following table. The CPI for January of each year is also provided. Deflate the stock price series and comment on the financial performance o
> Actuaries are analysts who specialize in the mathematics of risk. Actuaries often work for insurance companies and are responsible for setting premiums for insurance policies. Below are the median salaries for actuaries and the yearly CPI for four years.
> The American Institute of Certified Tax Planners reports that the average U.S. CPA works 60 hours per week during tax season. Do CPAs in states that have flat state income tax rates work fewer hours per week during tax season? Conduct a hypothesis test t
> Compute the price relatives for the four stocks making up the Boran index in exercise 20. Use the weighted aggregates of price relatives to compute the January of Year 3 and March of Year 3 Boran indexes. Exercise 20: Boran Stockbrokers, Inc., selects f
> Boran Stockbrokers, Inc., selects four stocks for the purpose of developing its own index of stock market behavior. Prices per share for a Year 1 base period, January of Year 3, and March of Year 3 follow. Base-year quantities are set on the basis of his
> Use the price data in exercise 18 to compute a Paasche index for the shipping cost if Year 5 quantities are 4000, 3000, 7500, and 3000 for the four products, respectively. Exercise 18: Nickerson Manufacturing Company has the following data on quantities
> Nickerson Manufacturing Company has the following data on quantities shipped and unit shipping costs for each of its four products: a. Compute the price relative for each product. b. Compute a weighted aggregate price index that reflects the shipping c
> Nielsen Research provides weekly ratings of nationally broadcast television programs. The mean weekly number of viewers for the 207 prime-time programs broadcast by five major televisions networks (ABC, CBS, FOX, NBC, and CW) for the 2017â€
> A sample of 15 students received the following rankings on midterm and final examinations in a statistics course. Compute the Spearman rank-correlation coefficient for the data and test for a significant correlation with α = .10. What is th
> Course evaluation ratings for four college instructors are shown in the following table. Use α = .05 and test for a significant difference among the rating for these instructors. What is your conclusion?
> A sample of 20 engineers employed with a company for three years has been rank ordered with respect to managerial potential. Some of the engineers attended the company’s management-development course, others attended an off-site managem
> A client wants to determine whether there is a significant difference in the time required to complete a program evaluation with the three different methods that are in common use. The times (in hours) required for each of 18 evaluators to conduct a prog
> The following data are product weights for the same items produced on two different production lines. Test for a difference between the product weights for the two lines. Use α = .05. Line 1 …………………………………………… Line 2 13.6 …………………………………………………. 13.7 13.8 …
> TextRequest reports that adults 18–24 years old send and receive 128 texts every day. Suppose we take a sample of 25–34 year olds to see if their mean number of daily texts differs from the mean for 18–24 year olds reported by TextRequest. a. State the n
> A study was designed to evaluate the weight-gain potential of a new poultry feed. A sample of 12 chickens was used in a six-week study. The weight of each chicken was recorded before and after the six-week test period. The differences between the before
> Twelve homemakers were asked to estimate the retail selling price of two models of refrigerators. Their estimates of selling price are shown in the following table. Use these data and test at the .05 level of significance to determine whether there is a
> According to the National Association of Realtors website (https://www.nar.realtor/sites/default/files/documents/metro-home-prices-q3-2017-single-family-2017-11-02.pdf), the national median sales price for single-family homes was $254,000 in 2018. Assume
> A survey asked the following question: Do you favor or oppose providing tax-funded vouchers or tax deductions to parents who send their children to private schools? Of the 2010 individuals surveyed, 905 favored the proposal, 1045 opposed the proposal, an
> Refer to the Hudson Marine data in exercise 53. a. Deseasonalize the data and use the deseasonalized time series to identify the trend. b. Use the results of part (a) to develop a quarterly forecast for next year based on trend. c. Use the seasonal index
> Refer to the Hudson Marine problem in exercise 53. a. Compute the centered moving average values for this time series. b. Construct a time series plot that also shows the centered moving average and original time series on the same graph. Discuss the dif
> Refer to the Hudson Marine problem in exercise 52. Suppose the quarterly sales values for the seven years of historical data are as follows. a. Use the following dummy variables to develop an estimated regression equation to account for any season and
> Hudson Marine provides boat sales, service, and maintenance. Boat trailers are one of its top sales items. The following table reports the number of trailers sold for the last seven years. a. Construct a time series plot. Does a linear trend appear to
> Refer to the Costello Music Company time series in exercise 49. a. Deseasonalize the data and use the deseasonalized time series to identify the trend. b. Use the results of part (a) to develop a quarterly forecast for next year based on trend. c. Use th
> Refer to the Costello Music Company problem in exercise 49. a. Using time series decomposition, compute the seasonal indexes for the four quarters. b. When does Costello Music experience the largest seasonal effect? Does this result appear reasonable? Ex
> In a study entitled How Undergraduate Students Use Credit Cards, it was reported that undergraduate students have a mean credit card balance of $3173. This figure was an all-time high and had increased 44% over the previous five years. Assume that a curr
> A sample containing years to maturity and yield for 40 corporate bonds are contained in the file CorporateBonds. a. What is the sample mean years to maturity for corporate bonds and what is the sample standard deviation? b. Develop a 95% confidence inter
> Consider the Costello Music Company problem in exercise 48. The quarterly sales data follow. a. Use the following dummy variables to develop an estimated regression equation to account for any seasonal and linear trend effects in the data: Qtr1 = 1 if
> The Costello Music Company has been in business for five years. During that time, sales of pianos increased from 12 units in the first year to 76 units in the most recent year. Fred Costello, the firm’s owner, wants to develop a forecas
> The following data show the price in dollars for a general admission ticket to the Magic Kingdom at Disney World from the year 2000 (period 1) to 2017 (period 18) (Travel 1 Leisure website). These data are in the file DisneyPrices. a. Construct a time-
> The Mayfair Department Store in Davenport, Iowa, is trying to determine the amount of sales lost while it was shut down during July and August because of damage caused by the Mississippi River flood. Sales data for January through June follow. a. Use
> Annual retail store revenue for Apple from 2007 to 2017 are shown below (investorapple website). a. Construct a time series plot. What type of pattern exists in the data? b. Using statistical software, develop a linear trend equation for this time seri
> The data contained in the file CrudeCost shows the U.S. refiner acquisition cost of crude oil in dollars per barrel (Energy Information Administration website). a. Construct a time series plot. What type of pattern exists in the data? b. Compute the line
> United Dairies, Inc., supplies milk to several independent grocers throughout Dade County, Florida. Managers at United Dairies want to develop a forecast of the number of half-gallons of milk sold per week. Sales data for the past 12 weeks follow. a. C
> The following table reports the percentage of stocks in a portfolio for nine quarters. Quarter …………………………………………………… Stock % 1st—Year 1 …………………………………………………… 29.8 2nd—Year 1 …………………………………………………… 31.0 3rd—Year 1 …………………………………………………… 29.9 4th—Year 1 …………………
> The weekly demand (in cases) for a particular brand of automatic dishwasher detergent for a chain of grocery stores located in Columbus, Ohio, follows. a. Construct a time series plot. What type of pattern exists in the data? b. Use a three-week moving
> A study was conducted to investigate browsing activity by shoppers. Shoppers were classified as nonbrowsers, light browsers, and heavy browsers. For each shopper in the study, a measure was obtained to determine how comfortable the shopper was in the sto
> According to the IRS, individuals filing federal income tax returns prior to March 31 received an average refund of $1056 in 2018. Consider the population of “last-minute” filers who mail their tax return during the last five days of the income tax perio
> The U.S. Department of Energy’s Fuel Economy Guide provides fuel efficiency data for cars and trucks (www.fueleconomy.gov). The file FuelEconomy2019 provides a portion of the data for 387 vehicles from the 2019 model year. The column labeled Class identi
> Refer to the data in exercise 31. a. Develop an estimated regression equation that can be used to predict Delay by using Industry and Quality. b. Plot the residuals obtained from the estimated regression equation developed in part (a) as a function of t
> Refer to the data in exercise 31. Consider a model in which only Industry is used to predict Delay. At a .01 level of significance, test for any positive autocorrelation in the data. Exercise 31: In baseball, an earned run is any run the opposing team s
> A study investigated the relationship between audit delay (Delay), the length of time from a company’s fiscal year-end to the date of the auditor’s report, and variables that describe the client and the auditor. Some o
> In baseball, an earned run is any run the opposing team scores off a pitcher except for a run scored as a result of fielding errors. The earned run average (ERA) is a statistic commonly used to compare the performance of pitchers; the ERA of a pitcher is
> Consumer Reports tested 19 different brands and models of road, fitness, and comfort bikes. Road bikes are designed for long road trips; fitness bikes are designed for regular workouts or daily commutes; and comfort bikes are designed for leisure rides o
> A sample containing years to maturity and yield (%) CorporateBonds for 40 corporate bonds is contained in the file CorporateBonds (Barron’s). a. Develop a scatter diagram of the data using x = years to maturity as the independent variable. Does a simple
> For the holiday season of 2017, nearly 59 percent of consumers planned to buy gift cards. According to the National Retail Federation, millennials like to purchase gift cards (Dayton Daily News website). Consider the sample data in the file GiftCards. Th
> A portion of a data set containing information for 45 mutual funds that are part of the Morningstar Funds 500 follows. The complete data set is available in the file named MutualFunds. The data set includes the following five variables: Fund Type: The ty
> The Cincinnati Zoo and Botanical Gardens had a record attendance of 1.87 million visitors in 2017 (Cincinnati Business Courier website). Nonprofit organizations such as zoos and museums are becoming more sophisticated in their use of data to improve the
> Consider the following hypothesis test: H0: µ = 22 Ha: µ ≠ 22 A sample of 75 is used and the population standard deviation is 10. Compute the p-value and state your conclusion for each of the following sample results. Use α = .01. a. x̅ = 23 b. x̅ = 25.1
> The Tire Rack, America’s leading online distributor of tires and wheels, conducts extensive testing to provide customers with products that are right for their vehicle, driving style, and driving conditions. In addition, the Tire Rack m
> Recall that in exercise 50 the personnel director for Electronics Associates developed the following estimated regression equation relating an employee’s score on a job satisfaction test to length of service and wage rate. yÌ
> Recall that in exercise 49, the admissions officer for Clearwater College developed the following estimated regression equation relating final college GPA to the student’s SAT mathematics score and high-school GPA. ŷ = 21.
> A partial computer output from a regression analysis follows. a. Compute the missing entries in this output. b. Use the F test and α = .05 to see whether a significant relationship is present. c. Use the t test and α = .05 t
> The personnel director for Electronics Associates developed the following estimated regression equation relating an employee’s score on a job satisfaction test to his or her length of service and wage rate. ŷ= 14.4 - 8.69x1 + 13.5x2 where x1 = length of