Question: Which samples show unequal variances? Use α = .10

> Find the sample proportions and test statistic for equal proportions. Find the p-value. a. Dissatisfied workers in two companies: x1 = 40, n1 = 100, x2 = 30, n2 = 100, α = .05, two tailed test. b. Rooms rented at least a week in advance at two hotels: x

> Calculate the test statistic and p-value for a test of equal population proportions. What is your conclusion? a. Left-tailed test, α = .10, x1 = 28, n1 = 336, x2 = 14, n2 = 112 b. Right-tailed test, α = .05, x1 = 276, n1 = 300, x2 = 440, n2 = 500 c. Two

> Calculate the test statistic and p-value for a test of equal population proportions. What is your conclusion? a. Right-tailed test, α = .10, x1 = 228, n1 = 240, x2 = 703, n2 = 760 b. Left-tailed test, α = .05, x1 = 36, n1 = 80, x2 = 66, n2 = 120 c. Two-

> Repeat the previous exercise, assuming unequal variances. Calculate the p-value using Excel, and show the Excel formula you used. Previous exercise: Do a two-sample test for equality of means assuming equal variances. Calculate the p-value. a. Compari

> A newly installed automatic gate system was being tested to see if the number of failures in 1,000 entry attempts was the same as the number of failures in 1,000 exit attempts. A random sample of eight delivery trucks was selected for data collection. Do

> Below is a random sample of shoe sizes for 12 mothers and their daughters. (a) At α = .01, does this sample show that women’s shoe sizes have increased? State your hypotheses and show all steps clearly. (b) Is the deci

> The coach told the high school swim team that times in the 200-yard individual medley in the Division I-AA Swim Championships typically are more than 1/2 second faster than their seed times going into the meet. At α = .05, do these times (i

> The U.S. government’s “Cash for Clunkers” program encouraged individuals to trade in their old gas-guzzlers for new, more efficient vehicles. At α = .05, do the data below support the hy

> Blue Box is testing a new “half price on Tuesday” policy on DVD rentals at a sample of 10 locations. (a). At α = .10, do the data show that the mean number of Tuesday rentals has increased? (b). Is th

> In preliminary tests of a vaccine that may help smokers quit by reducing the “rush” from tobacco, 64 subjects who wanted to quit smoking were given either a placebo or the vaccine. Of the 32 in the placebo group, only 3 quit smoking for 30 days (the U.S.

> A 20-minute consumer survey mailed to 500 adults aged 25–34 included a $5 Starbucks gift certificate. The same survey was mailed to 500 adults aged 25–34 without the gift certificate. There were 65 responses from the first group and 45 from the second gr

> A survey of 100 mayonnaise purchasers showed that 65 were loyal to one brand. For 100 bath soap purchasers, only 53 were loyal to one brand. Form a 95 percent confidence interval for the difference of proportions. Does it include zero?

> This table shows partial results for a one-factor ANOVA, (a). Calculate the F test statistic. (b). Calculate the p-value using Excel’s function 5F.DIST.RT (F,DF1,DF2). (c). Find the critical value F.05 from Appendix F or using Excel

> A manufacturing process drills holes in sheet metal that are supposed to be .5000 cm in diameter. Before and after a new drill press is installed, the hole diameter is carefully measured (in cm) for 12 randomly chosen parts. At α = .05, do

> An experimental surgical procedure is being studied as an alternative to the old method. Both methods are considered safe. Five surgeons perform the operation on two patients matched by age, sex, and other relevant factors, with the results shown. The ti

> The American Bankers Association reported that, in a sample of 120 consumer purchases in France, 60 were made with cash, compared with 26 in a sample of 50 consumer purchases in the United States. Construct a 90 percent confidence interval for the differ

> Consider a one-factor ANOVA with n1 = 6, n2 = 5, n3 = 4, n4 = 6, n5 = 4. (a). How many possible comparisons of means are there? (b). State the degrees of freedom for Tukey’s T. (c). Find the critical value of Tukey’s T for α = .05.

> Consider a one-factor ANOVA with n1 = 9, n2 = 10, n3 = 7, n4 = 8. (a). How many possible comparisons of means are there? (b). State the degrees of freedom for Tukey’s T. (c). Find the critical value of Tukey’s T for α = .05.

> For each data set: (a) State the hypotheses. (b) Use Excel’s Data Analysis (or MegaStat or MINITAB) to perform the one-factor ANOVA, using α = .05. (c) State your conclusion about the population means. (d) Interpret th

> For each data set: (a) State the hypotheses. (b) Use Excel’s Data Analysis (or MegaStat or MINITAB) to perform the one-factor ANOVA, using α = .05. (c) State your conclusion about the population means. (d) Interpret th

> For each data set: (a) State the hypotheses. (b) Use Excel’s Data Analysis (or MegaStat or MINITAB) to perform the one-factor ANOVA, using α = .05. (c) State your conclusion about the population means. (d) Interpret th

> For each data set: (a) State the hypotheses. (b) Use Excel’s Data Analysis (or MegaStat or MINITAB) to perform the one-factor ANOVA, using α = .05. (c) State your conclusion about the population means. (d) Interpret th

> In a one-factor ANOVA with sample sizes n1 = 8, n2 = 5, n3 = 6, n4 = 6, the test statistic was Fcalc = 3.251. (a). State the hypotheses. (b). State the degrees of freedom for the test. (c). What is the critical value of F for α = .05? (d). What is y

> In a one-factor ANOVA with sample sizes n1 = 5, n2 = 7, n3 = 6, n4 = 7, n5 = 5, the test statistic was Fcalc = 2.447. (a). State the hypotheses. (b). State the degrees of freedom for the test. (c). What is the critical value of F for α = .10? (d). W

> Oxnard Petro, Ltd. has three suppliers of catalysts. Orders are placed with each supplier every 15 working days, or about once every 3 weeks. The delivery time (days) is recorded for each order over 1 year. Are the main effects significant? Is there an i

> (a) At α = .05, does the following sample show that daughters are taller than their mothers? (b) Is the decision close? (c) Why might daughters tend to be taller than their mothers? Why might they not? Daughter's Height (cm) Mother's

> A market research firm is testing consumer reaction to a new shampoo on four age groups in four regions. There are five consumers in each test panel. Each consumer completes a 10-question product satisfaction instrument with a 5-point scale (5 is the hig

> Oxnard Petro, Ltd., has three interdisciplinary project development teams that function on an ongoing basis. Team members rotate from time to time. Every 4 months (three times a year) each department head rates the performance of each project team (using

> A small independent stock broker has created four sector portfolios for her clients. Each portfolio always has five stocks that may change from year to year. The volatility (coefficient of variation) of each stock is recorded for each year. Are the main

> A beer distributor is comparing quarterly sales of Coors Light (number of six-packs sold) at three convenience stores. Does this sample provide sufficient evidence to conclude that there is a significant difference in treatment means? Store 1 Store

> Five statistics professors are using the same textbook with the same syllabus and common exams. At the end of the semester, the department committee on instruction looked at average exam scores. Does this sample provide sufficient evidence to conclude th

> Engineers are testing company fleet vehicle fuel economy (miles per gallon) performance by using different types of fuel. One vehicle of each size is tested. Does this sample provide sufficient evidence to conclude that there is a significant difference

> Concerned about Friday absenteeism, management examined absenteeism rates for the last three Fridays in four assembly plants. Does this sample provide sufficient evidence to conclude that there is a significant difference in treatment means? Plant 1

> For each data set, use Hartley’s test to test the hypothesis of equal variances, using the 5 percent table of critical values from Table 11.5 and the largest and smallest sample variances from your previous ANOVA. Optional challenge: If

> Using the following Excel results: (a). What was the overall sample size? (b). How many groups were there? (c). Write the hypotheses. (d). Find the critical value of F for α = .10. (e). Calculate the test statistic. (f). Do the popu

> For each data set, use Hartley’s test to test the hypothesis of equal variances, using the 5 percent table of critical values from Table 11.5 and the largest and smallest sample variances from your previous ANOVA. Optional challenge: If

> Construct a 95 percent confidence interval for the difference of mean monthly rent paid by undergraduates and graduate students. What do you conclude? Undergraduate Student Rents (n = 10) 820 780 870 670 800 790 810 680 1,000 730 Graduate Student Re

> For each data set, use Hartley’s test to test the hypothesis of equal variances, using the 5 percent table of critical values from Table 11.5 and the largest and smallest sample variances from your previous ANOVA. Optional challenge: If

> For each data set, use Hartley’s test to test the hypothesis of equal variances, using the 5 percent table of critical values from Table 11.5 and the largest and smallest sample variances from your previous ANOVA. Optional challenge: If

> In a one-factor ANOVA with n1 = 7, n2 = 6, n3 = 5, n4 = 5, and n5 = 7, the sample standard deviations were s1 = 12, s2 = 24, s3 = 16, s4 = 46, and s5 = 27. For Hartley’s test: (a). State the hypotheses. (b). Calculate the degrees of freedom. (c). Fin

> In a one-factor ANOVA with n1 = 6, n2 = 4, and n3 = 5, the sample variances were s12 =121, s22 = 929, and s32 5 456. For Hartley’s test: (a). State the hypotheses. (b). Calculate the degrees of freedom. (c). Find the critical value at the 5 percent l

> Use MegaStat, MINITAB, or another software package to perform Tukey’s test for significant pairwise differences. Perform the test using both the 5 percent and 1 percent levels of significance. Refer to Exercise 11.8. Which pairs of mea

> Use MegaStat, MINITAB, or another software package to perform Tukey’s test for significant pairwise differences. Perform the test using both the 5 percent and 1 percent levels of significance. Refer to Exercise 11.7. Which pairs of mea

> Use MegaStat, MINITAB, or another software package to perform Tukey’s test for significant pairwise differences. Perform the test using both the 5 percent and 1 percent levels of significance. Refer to Exercise 11.6. Which pairs of mea

> Examine the data below showing the weights (in pounds) of randomly selected checked bags for an airline’s flights on the same day. (a) At α 5 = .05, is the mean weight of an international bag greater? Show the hypothese

> Use MegaStat, MINITAB, or another software package to perform Tukey’s test for significant pairwise differences. Perform the test using both the 5 percent and 1 percent levels of significance. Refer to Exercise 11.5. Which pairs of mea

> Researchers at the Mayo Clinic have studied the effect of sound levels on patient healing and have found a significant association (louder hospital ambient sound level is associated with slower postsurgical healing). Based on the Mayo Clinic’s experience

> In trials of an experimental Internet-based method of learning statistics, pre-tests and post-tests were given to two groups: traditional instruction (22 students) and Internet-based (17 students). Pre-test scores were not significantly different. On the

> Which samples show unequal variances? Use α = .05 in all tests. Show the critical values and degrees of freedom clearly and illustrate the decision rule. a. s1 = 5.1, n1 = 11, s2 = 3.2, n2 = 8, two-tailed test b. s1 = 221, n1 = 8, s2 = 445, n2 = 8, left

> A survey of 100 cigarette smokers showed that 71 were loyal to one brand, compared to 122 of 200 toothpaste users. Construct a 90 percent confidence interval for the difference in proportions.

> A study showed that 36 of 72 cell phone users with a headset missed their exit, compared with 12 of 72 talking to a passenger. Construct a 95 percent confidence interval for the difference in proportions.

> Using the following Excel results: (a). What was the overall sample size? (b). How many groups were there? (c). Write the hypotheses. (d). Find the critical value of F for α = .05. (e). Calculate the test statistic. (f). Do the popu

> A 30-minute consumer survey mailed to 500 adults aged 25234 included a $10 gift certificate to Borders. The same survey was mailed to 500 adults aged 25234 without the gift certificate. There were 185 responses from the first group and 45 from the second

> From a telephone log, an executive finds that 36 of 128 incoming telephone calls last week lasted at least 5 minutes. She vows to make an effort to reduce the length of time spent on calls. The phone log for the next week shows that 14 of 96 incoming cal

> In 2009, a sample of 200 in-store shoppers showed that 42 paid by debit card. In 2012, a sample of the same size showed that 62 paid by debit card. (a). Formulate appropriate hypotheses to test whether the percentage of debit card shoppers increased by

> When tested for compliance with Sarbanes-Oxley requirements for financial records and fraud protection, 14 of 180 publicly traded business services companies failed, compared with 7 of 67 computer hardware, software, and telecommunications companies. (a

> Are large companies more profitable per dollar of assets? The largest 500 companies in the world were ranked according to their number of employees, with groups defined as follows: Small = under 25,000 employees, Medium = 25,000 to 49,999 employees, Larg

> A special bumper was installed on selected vehicles in a large fleet. The dollar cost of body repairs was recorded for all vehicles that were involved in accidents over a 1-year period. Those with the special bumper are the test group and the other vehic

> Do a two-sample test for equality of means assuming equal variances. Calculate the p-value. a. Comparison of GPA for randomly chosen college juniors and seniors: /1 = 3.05, s1 = .20, n1 = 15, /2 = 3.25, s2 = .30, n2 = 15, α = .025, left-tailed test. b.

> Explain why a put option on a bond is conceptually the same as a call option on interest rates.

> What does it mean to say that a proposed merger will take advantage of available economies of scale? Suppose Eastern Power Co. and Western Power Co. are located in different time zones. Both operate at 60 percent of capacity except for peak periods, when

> Suppose a firm has a book balance of $2 million. At the automatic teller machine (ATM), the cash manager finds out that the bank balance is $2.5 million. What is the situation here? If this is an ongoing situation, what ethical dilemma arises?

> What is the duration of a bond with four years to maturity and a coupon of 8.6 percent paid annually if the bond sells at par?

> The treasurer of a major U.S. firm has $30 million to invest for three months. The annual interest rate in the United States is .17 percent per month. The interest rate in Great Britain is .61 percent per month. The spot exchange rate is £.64, and the th

> Essence of Skunk Fragrances, Ltd., sells 5,450 units of its perfume collection each year at a price per unit of $480. All sales are on credit with terms of 1/10, net 40. The discount is taken by 35 percent of the customers. What is the total amount of th

> Cholern Electric Company (CEC) is a public utility that provides electricity to the central Colorado area. Recent events at its Mile-High Nuclear Station have been discouraging. Several shareholders have expressed concern over last yearâ€&#153

> Lewellen Products has projected the following sales for the coming year: Sales in the year following this one are projected to be 15 percent greater in each quarter. a. Calculate payments to suppliers assuming that the company places orders during each

> Submarine Manufacturing is investigating a lockbox system to reduce its collection time. It has determined the following: The total collection time will be reduced by three days if the lockbox system is adopted. a. What is the PV of adopting the system

> Are the following statements true or false? Explain why. a. If the general price index in Great Britain rises faster than that in the United States, we would expect the pound to appreciate relative to the dollar. b. Suppose you are a German machine tool

> If a firm is selling futures contracts on lumber as a hedging strategy, what must be true about the firm’s exposure to lumber prices?

> What are DIP loans? Where do DIP loans fall in the APR?

> What are the different inventory types? How do the types differ? Why are some types said to have dependent demand, whereas other types are said to have independent demand?

> In an ideal economy, net working capital is always zero. Why might net working capital be positive in a real economy?

> If a textile manufacturer wanted to hedge against adverse movements in cotton prices, it could buy cotton futures contracts or buy call options on cotton futures contracts. What would be the pros and cons of the two approaches?

> Which would a firm prefer: A net collection float or a net disbursement float? Why?

> What is the duration of a bond with three years to maturity and a coupon of 6.1 percent paid annually if the bond sells at par?

> A mail-order firm processes 5,450 checks per month. Of these, 70 percent are for $55 and 30 percent are for $80. The $55 checks are delayed two days on average; the $80 checks are delayed three days on average. a. What is the average daily collection flo

> Use Figure 31.1 to answer the following questions. Suppose interest rate parity holds, and the current six-month risk-free rate in the United States is 1.9 percent. What must the six-month risk-free rate be in Great Britain? In Japan? In Switzerland?

> Turnover Chen, Inc., has an average collection period of 34 days. Its average daily investment in receivables is $61,300. What are annual credit sales? What is the receivables turnover?

> The shareholders of Flannery Company have voted in favor of a buyout offer from Stultz Corporation. Information about each firm is given here: Flannery’s shareholders will receive one share of Stultz stock for every three shares they

> Suppose the exchange rate for the Swiss franc is quoted as SF 1.09 in the spot market and SF 1.11 in the 90-day forward market. a. Is the dollar selling at a premium or a discount relative to the franc? b. Does the financial market expect the franc to st

> Consider the following financial statement information for the Rivers Corporation: Calculate the operating and cash cycles. How do you interpret your answer? Item Beginning Ending Inventory $17,385 $19,108 Accounts receivable 13,182 13,973 Accounts

> Given that many multinationals based in many countries have much greater sales outside their domestic markets than within them, what is the particular relevance of their domestic currency?

> What is the absolute priority rule?

> Describe the advantages and disadvantages of a taxable merger as opposed to a tax-free exchange. What is the basic determinant of tax status in a merger? Would an LBO be taxable or nontaxable? Explain.

> In each of the following pairings, indicate which firm would probably have a longer credit period and explain your reasoning. a. Firm A sells a miracle cure for baldness; Firm B sells toupees. b. Firm A specializes in products for landlords; Firm B speci

> What are the costs of shortages? Describe them.

> A company produces an energy-intensive product and uses natural gas as the energy source. The competition primarily uses oil. Explain why this company is exposed to fluctuations in both oil and natural gas prices.

> Are poison pills good or bad for stockholders? How do you think acquiring firms are able to get around poison pills?

> Why is a preferred stock with a dividend tied to short-term interest rates an attractive short-term investment for corporations with excess cash?

> At one point, Duracell International confirmed that it was planning to open battery manufacturing plants in China and India. Manufacturing in these countries allows Duracell to avoid import duties of between 30 and 35 percent that have made alkaline batt

> Explain the purchase accounting method for mergers. What is the effect on cash flows? On EPS?

> What is the difference between liquidation and reorganization?

> You are short 25 gasoline futures contracts, established at an initial settle price of $1.36 per gallon, where each contract represents 42,000 gallons. Over the subsequent four trading days, gasoline settles at $1.33, $1.37, $1.39, and $1.44, respectivel

> Penn Corp. is analyzing the possible acquisition of Teller Company. Both firms have no debt. Penn believes the acquisition will increase its total aftertax annual cash flow by $1.3 million indefinitely. The current market value of Teller is $27 million,

> The Litzenberger Company has projected the following quarterly sales amounts for the coming year: a. Accounts receivable at the beginning of the year are $335. The company has a 45-day collection period. Calculate cash collections in each of the four qu

> Your firm has an average receipt size of $119. A bank has approached you concerning a lockbox service that will decrease your total collection time by two days. You typically receive 5,650 checks per day. The daily interest rate is .015 percent. If the b

> Suppose the Japanese yen exchange rate is ¥126 5 $1, and the British pound exchange rate is £1 5 $1.53. a. What is the cross-rate in terms of yen per pound? b. Suppose the cross-rate is ¥195.8 5 £1. Is there an arbitrage opportunity here? If there is, ex

> A firm offers terms of 1/10, net 30. What effective annual interest rate does the firm earn when a customer does not take the discount? Without doing any calculations, explain what will happen to this effective rate if: a. The discount is changed to 2 pe

> What are some of the factors that determine the length of the credit period? Why is the length of the buyer’s operating cycle often considered an upper bound on the length of the credit period?