Log out Go to App
Go to App

Learning Materials

Features

Discover

Chapter 8: Q 8.137. (page 344)

Big Bucks. In the article "The \(350,000 Club" (The Business Journal, Vol. 24, Issue 14, Pp. 80-82), J. Trunelle et al. examined Arizona public-company executives with salaries and bonuses totaling over \)350,000 The following data provide the salaries, to the nearest thousand dollars, of a random sample of 20 such executives.

Short Answer

Expert verified

It is reasonable to apply the t-interval procedure to obtain the confidence interval of the population mean based on this sample.

Step by step solution

01

Given information

516574560623600
770680672745450
450545630650461
836404428620604
02

Explanation

Now, draw a probability plot for the given data.

Now construct a box plot for a given data.

03

Explanation

Now construct the histogram for the given data.

The sample size here is moderate (n=20) We can observe from the graphs that there is no outlier in the sample. The plotted points fall closely along a straight line, indicating that the variable under study is approximately regularly distributed. As a result, applying the t-interval approach to estimate the confidence interval of the population means based on this sample is appropriate.

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Start your free trial

Over 30 million students worldwide already upgrade their learning with Vaia!

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

Preliminary data analyses indicate that you can reasonably apply the z- interval procedure

Poverty and Dietary Calcium. Calcium is the most abundant mineral in the human body and has several important functions. Most body calcium is stored in the bones and teeth, where it functions to support their structure. Recommendations for calcium are provided in Dietary Reference Intakes, developed by the Institute of Medicine of the National Academy of Sciences. The recommended adequate intake (RAI) of calcium for adults (ages 19-50) is 100milligrams (mg) per day. A simple random sample of 18adults with incomes below the poverty level gave the following daily calcium intake

Explain the effect on the margin of error and hence the effect on the accuracy of estimating a population mean by a sample mean.

Increasing the confidence level while keeping same sample size.

Assume that the population standard deviation is known and decide weather use of the z-interval procedure to obtain a confidence interval for the population mean is reasonable. Explain your answers.

The variable under consideration is very close to being normally distributed, and the sample size is 10.

A confidence interval for a population mean has length 20.

a. Determine the margin of error.

b. If the sample mean is 60, obtain the confidence interval.

c. Construct a graph that illustrates your results.

Bicycle Commuting Times. A city planner working on bikeways designs a questionnaire to obtain information about local bicycle commuters. One of the questions asks how long it takes the rider to pedal from home to his or her destination. A sample of local bicycle commuters yields the following times, in minutes.

a. Find a 90%confidence interval for the mean commuting time of all local bicycle commuters in the city. (Note: The sample mean and sample standard deviation of the data are 25.82minutes and 7.71minutes, respectively.)

b. Interpret your result in part (a).

c. Graphical analyses of the data indicate that the time of 48min utes may be an outlier. Remove this potential outlier and repeat part (a). (Note: The sample mean and sample standard deviation of the abridged data are 24.76 and 6.05, respectively.)

d. Should you have used the procedure that you did in part (a)? Explain your answer.
See all solutions

Recommended explanations on Math Textbooks

Logic and Functions

Read Explanation

Probability and Statistics

Read Explanation

Mechanics Maths

Read Explanation

Decision Maths

Read Explanation

Geometry

Read Explanation

Calculus

Read Explanation
View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.

Sign-up for free