/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Q. 100 Which inference method?a. A city... [FREE SOLUTION] | 91影视

91影视

Log out

Learning Materials

Features

Discover

Chapter 10: Q. 100 (page 691)

Which inference method?

a. A city planner wants to determine if there is convincing evidence of a difference in the average number of cars passing through two different intersections. He randomly selects 12times between 6:00a.m. and 10:00p.m., and he and his assistant count the number of cars passing through each intersection during the 10-minute interval that begins at that time.

b. Are more than 75%of Toyota owners generally satisfied with their vehicles? Let鈥檚 design a study to find out. We鈥檒l select a random sample of 400 Toyota owners. Then we鈥檒l ask each individual in the sample, 鈥淲ould you say that you are generally satisfied with your Toyota vehicle?鈥�

c. Are male college students more likely to binge drink than female college students? The Harvard School of Public Health surveys random samples of male and female undergraduates at four-year colleges and universities about whether they have engaged in binge drinking.

d. A bank wants to know which of two incentive plans will most increase the use of its credit cards and by how much. It offers each incentive to a group of current credit card customers, determined at random, and compares the amount charged during the following 6 months.

Short Answer

Expert verified

a. Paired t test for the mean difference

b. One sample z test for a proportion

c. Two sample z test for the difference in proportions

d. Paired t interval for the mean difference

Step by step solution

01

Part (a): Step 1 : Given information

We have given 2samples for the case study

We have to find a suitable method to determine if the claim that there is a difference in the average number of cars passing through two different intersections is correct or not.

02

Part (a): Step 2: Explanation

To determine the correctness of the claim, we use hypothesis testing.

Here, we have given 2samples containing the same 12times. Also, samples are dependent and are estimated at the mean or average.

Hence, we use a paired t-test for the mean difference.

03

Part (b): Step 1: Given information

We have given 1samples for the case study

We have to find a suitable method to determine if the claim that "more than 75%Toyota owners are generally satisfied with their vehicles" is true or not.

04

Part (b): Step 2: Explanation

To determine the correctness of the claim, we use hypothesis testing.

Here, we have given only 1a sample.

Hence, we use a one-sample test for a proportion.

05

Part (c): Step 1: Given Information

We have given 2samples for the case study

We have to find a suitable method to determine if the claim that "male college students are more likely to drink than female college students" is true or not.

06

Part (c): Step 2: Explanation

To determine the correctness of the claim, we use hypothesis testing.

Here, we have given 2samples containing different subjects. Hence, samples are independent and are estimated at proportions.

Hence, we use two-sample z tests for the difference in proportions.

07

Part (d): Step 1: Given information 

We have given 2samples for the case study

We have to find a suitable method to help the bank to know which of the two incentive plans will most increase the use of its credit cards and by how much

08

Part (d): Step 2: Explanation

To estimate the difference in the mean amount charged, we use paired testing.

Here, we have given 2samples containing the same subjects. Hence, samples are dependent and are estimated by paired tests.

Hence, we use a paired t-interval for the mean difference.

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.

Over 30 million students worldwide already upgrade their learning with 91影视!

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

At a baseball game, 42of 65randomly selected people own an iPod. At a rock concert occurring at the same time across town, 34of 52randomly selected people own an iPod. A researcher wants to test the claim that the proportion of iPod owners at the two venues is different. A 90%confidence interval for the difference (Game 鈭� Concert) in population proportions is (鈭�0.154,0.138). Which of the following gives the correct outcome of the researcher鈥檚 test of the claim?

a. Because the confidence interval includes 0, the researcher can conclude that the proportion of iPod owners at the two venues is the same.

b. Because the center of the interval is -0.008, the researcher can conclude that a higher proportion of people at the rock concert own iPods than at the baseball game.

c. Because the confidence interval includes 0, the researcher cannot conclude that the proportion of iPod owners at the two venues is different.

d. Because the confidence interval includes more negative than positive values, the researcher can conclude that a higher proportion of people at the rock concert own iPods than at the baseball game.

e. The researcher cannot draw a conclusion about a claim without performing a significance test.

Where鈥檚 Egypt? In a Pew Research poll, 287out of 522randomly selected U.S. men were able to identify Egypt when it was highlighted on a map of the Middle East. When520 randomly selected U.S. women were asked, 233 were able to do so.

a. Construct and interpret a 95% confidence interval for the difference in the true

proportion of U.S. men and U.S. women who can identify Egypt on a map.

b. Based on your interval, is there convincing evidence of a difference in the true

proportions of U.S. men and women who can identify Egypt on a map? Justify your

answer.

Digital video disks A company that records and sells rewritable DVDs wants to compare the reliability of DVD fabricating machines produced by two different manufacturers. They randomly select 500DVDs produced by each fabricator and find that 484of the disks produced by the first machine are acceptable and 480of the disks produced by the second machine are acceptable. If p1,p2are the proportions of acceptable DVDs produced by the first and second machines, respectively, check if the conditions for calculating a confidence interval for p1-p2are met.

In an experiment to learn whether substance M can help restore memory, the brains of 20rats were treated to damage their memories. First, the rats were trained to run a maze. After a day, 10rats (determined at random) were given substance M and 7of them succeeded in the maze. Only 2of the 10control rats were successful. The two-sample z test for the difference in the true proportions

a. gives z=2.25,P<0.02 .

b. gives z=2.60,P<0.005 .

c. gives z=2.25,P<0.04 but not<0.02

d. should not be used because the Random condition is violated.

e. should not be used because the Large Counts condition is violated.

Young adults living at home A surprising number of young adults (ages 19

to 25) still live in their parents鈥� homes. The National Institutes of Health surveyed

independent random samples of 2253men and 2629women in this age group. The survey found that 986 of the men and 923 of the women lived with their parents.

a. Construct and interpret a 99%confidence interval for the difference in the true

proportions of men and women aged 19-25who live in their parents鈥� homes.

b. Does your interval from part (a) give convincing evidence of a difference between the population proportions? Justify your answer.
See all solutions

Recommended explanations on Math Textbooks

Calculus

Read Explanation

Probability and Statistics

Read Explanation

Theoretical and Mathematical Physics

Read Explanation

Decision Maths

Read Explanation

Discrete Mathematics

Read Explanation

Geometry

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.