Ask Question, Ask an Expert

+61-413 786 465

info@mywordsolution.com

Ask Statistics and Probability Expert

Instructions: This problem set is due by the end of class on Thursday, November 15th. You can either hand in a paper copy, or email a copy to amcquoid@u.edu. When you submit through email, please title the file "firstname_lastname_ps5". NO LATE homework will be acknowledged. The complete answer comprises not just a numerical (or graphical or tabular) answer, however an interpretation of the result. You are expected to give thorough answers to problems which ask for a discussion, interpretation or description. The overall problem set grade depends mainly on your capability to describe.

problem: (Anderson, Sweeney, and Williams, 11th ed, 8.8)

The National Quality Research Center at University of Michigan offers a quarterly measure of consumer opinions regarding products and services (The Wall Street Journal, February 18, 2003). The survey of 10 restaurants in the Fast Food/Pizza group showed a sample mean customer satisfaction index of 71. Past data point out that the population standard deviation of the index has been relatively stable with σ = 5

a) What assumption must the researcher be willing to make if a margin of error is desired?
b) Using 95% confidence, determine the margin of error?
c) Determine the margin of error if 99% confidence is desired?

problem: (Anderson, Sweeney, and Williams, 11th ed, 8.10)

Playbill magazine reported that the mean annual household income of its readers is $119,155 (Playbill, January 2006). Suppose this estimate of the mean annual household income is based on the sample of 80households, and based on past studies, the population standard deviation is known to be σ = $30; 000.

a) Make a 90% confidence interval estimate of the population mean.
b) Make a 95% confidence interval estimate of the population mean.
c) Make a 99% confidence interval estimate of the population mean.
d) Discuss what happens to the width of confidence interval as the confidence level is raised.

Does this result seem reasonable? Describe.

problem: (Anderson, Sweeney, and Williams, 11th ed, 8.16)

The mean number of hours of flying time for pilots at the Continental Airlines is 49 hours per month (The Wall Street Journal, February 25, 2003). Suppose that this mean was based on actual flying times for a sample of 100 Continental pilots and that the sample standard deviation was 8.5 hours.

a) At 95% confidence, determine the margin of error?
b) Determine the 95% confidence interval estimate of the population mean flying time for the pilots?

c) The mean number of hours of flying time for the pilots at United Airlines is 36 hours per month. Use your outcomes from part (b) to discuss differences between the flying times for the pilots at the two 1airlines. The Wall Street Journal reported United Airlines as having the highest labor cost among all airlines. Does the information in this exercise give insight as to why United Airlines might expect the higher labor costs?

problem: (Anderson, Sweeney, and Williams, 11th ed, 8.19)

The average cost per night of a hotel room in the New York City is $273 (SmartMoney, March 2009). Suppose this estimate is based on the sample of 45 hotels and which the sample standard deviation is $65.

a) With 95% confidence, determine the margin of error?
b) Determine the 95% confidence interval estimate of the population mean?
c) Two years ago, the average cost of a hotel room in the New York City was $229. Discuss the change in cost over two-year period.

problem: (Anderson, Sweeney, and Williams, 11th ed, 8.26)

The average cost of gallon of unleaded gasoline in the Greater Cincinnati was reported to be $2.41 (The Cincinnati Enquirer, February 3, 2006). Throughout periods of rapidly modifying prices, the newspaper samples service stations and prepares reports on gasoline prices frequently. Suppose the standard deviation is $.15 for the price of a gallon of unleaded regular gasoline, and recommend the suitable sample size for the newspaper to use if they wish to report a margin of error at 95% confidence.

a) Assume that the desired margin of error is $.07.
b) Assume that the desired margin of error is $.05.
c) Assume that the desired margin of error is $.03.

problem: (Anderson, Sweeney, and Williams, 11th ed, 8.38)

According to Thomson Financial, through January 25, 2006, the majority of companies reporting profits had beaten estimates (Business Week, February 6, 2006). The sample of 162 companies showed 104 beat estimates, 29 matched estimates, and 29 fell short.

a) What is the point estimate of the proportion which fell short of estimates?
b) Determine the margin of error and provide a 95% confidence interval for the proportion which beat estimates.
c) How big a sample is required if the desired margin of error is .05?

Statistics and Probability, Statistics

  • Category:- Statistics and Probability
  • Reference No.:- M9255

Have any Question? 


Related Questions in Statistics and Probability

A national center for health statistics report based on

A National Center for Health Statistics report based on 1985 data states that 30 percent of American adults smoke. Consider a simple random sample of 17 adults. Find the probability that the number of smokers in the samp ...

Honda is the manufacturer of 4 of the top 9 vehicles in

Honda is the manufacturer of 4 of the top 9 vehicles in terms of fuel economy. - Determine the probability distribution for the number of Hondas in a sample of 3 cars chosen from the top 9? - What is the likelihood that ...

Prior data indicates if a planter machine is operating

Prior data indicates if a planter machine is operating "properly," the length of the planter produced by the machine can be modeled as being normally distributed with a mean of 107 centimeters and a standard deviation of ...

Show worksuppose you are thinking of purchasing the moore

Show Work Suppose you are thinking of purchasing the Moore Co.'s common stock today. If you expect Moore to pay $1.2, $1.26, $1.323, and $1.39 dividends at the end of year one, two, three, and four respectively and you b ...

A professor records the following final exam scores 68 6 m

A professor records the following final exam scores: 68 6 (M SD). Students scoring in the top 18% get an A. What is the cutoff score for the top 18% in this example?

1 for a normal distribution with mu 500 and sigma 100 a

1. For a normal distribution with μ = 500 and σ = 100, a. What is the percentile rank for X = 550? b. What is the percentile rank for X = 650? c. What is the percentile rank for X = 450? 2. For a normal distribution with ...

This table summarizes the results from alongtermrandomized

This table summarizes the results from along+termrandomized clinicaltrial to  determine whether aspirin reduces the risk of heart attack. Researchers  randomly assigned a large sample of healthy male physicians (22,071) ...

Monroe inc is evaluating a project the company uses 138

Monroe, Inc, is evaluating a project. The company uses 13.8 percent discount rate for this project. cost and cash flows are shown in the table. What is the NPV of the project? year. Project 0. ($11,368,000) 1. $2,187,590 ...

You are working with a moe of -4 and a confidence level of

You are working with a MOE of +/-4% and a confidence level of 95%. P and Q =.50, and your CPI is $25.00. The company you work for needs to make a decision as to whether they may need different advertising for men and wom ...

Industries recently commissioned management consultants to

Industries recently commissioned management consultants to estimate an appropriate rate for investment projects with the same risk as the firm. Unfortunately, part of the report was lost, and you have been asked to calcu ...

  • 4,153,160 Questions Asked
  • 13,132 Experts
  • 2,558,936 Questions Answered

Ask Experts for help!!

Looking for Assignment Help?

Start excelling in your Courses, Get help with Assignment

Write us your full requirement for evaluation and you will receive response within 20 minutes turnaround time.

Ask Now Help with Problems, Get a Best Answer

Why might a bank avoid the use of interest rate swaps even

Why might a bank avoid the use of interest rate swaps, even when the institution is exposed to significant interest rate

Describe the difference between zero coupon bonds and

Describe the difference between zero coupon bonds and coupon bonds. Under what conditions will a coupon bond sell at a p

Compute the present value of an annuity of 880 per year

Compute the present value of an annuity of $ 880 per year for 16 years, given a discount rate of 6 percent per annum. As

Compute the present value of an 1150 payment made in ten

Compute the present value of an $1,150 payment made in ten years when the discount rate is 12 percent. (Do not round int

Compute the present value of an annuity of 699 per year

Compute the present value of an annuity of $ 699 per year for 19 years, given a discount rate of 6 percent per annum. As