Log out Go to App
Go to App

Learning Materials

Features

Discover

Chapter 10: Q. 64 (page 658)

Dropping out You have data from interviews with a random sample of students who failed to graduate from a particular college in 7years and also from a random sample of students who entered at the same time and did graduate. You will use these data to compare the percentages of students from rural backgrounds among dropouts and graduates.

Short Answer

Expert verified

Two proportion z-test.

Step by step solution

01

Given Information

Given in the question that,data from interviews with a random sample of students who failed to graduate from a particular college inyears and also from a random sample of students who entered at the same time and did graduate

02

Explanation

The z- test for two sample proportions is a technique of the statistics that is check out if there is a difference in the proportions of two populations or not. Here, it is required to compare the percentage of students from rural background.

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

Thirty-five people from a random sample of 125workers from Company A admitted to using sick leave when they weren’t really ill. Seventeen employees from a random sample of 68workers from Company B admitted that they had used sick leave when they weren’t ill. A 95% confidence interval for the difference in the proportions of workers at the two companies who would admit to using sick leave when they weren’t ill is

(a) 0.03±(0.28)(0.72)125+(0.25)(0.75)68

(b) localid="1650367573248" 0.03±1.96(0.28)(0.72)125+(0.25)(0.75)68

(c) 0.03±1.645(0.28)(0.72)125+(0.25)(0.75)68

(d)

0.03±1.96(0.269)(0.731)125+(0.269)(0.731)68

(e) 0.03±1.645(0.269)(0.731)125+(0.269)(0.731)68

48. Did the randomization produce similar groups? First, compare the two groups of birds in the first year. The only difference should be the
chance effect of the random assignment. The study report says: “In the experimental year, the degree of synchronization did not differ between
food-supplemented and control females.” For this comparison, the report gives t=-1.05.
(a) What type of tstatistic (one-sample, paired, or two-sample) is this? Justify your answer.
(b) Explain how this value of t leads to the quoted conclusion.

The power takeoff driveline on tractors used in agriculture is a potentially serious hazard to operators of farm equipment. The driveline is covered by a shield in new tractors, but for a variety of reasons, the shield is often missing on older tractors. Two types of shields are the bolt-on and the flip-up. It was believed that the bolt-on shield was perceived as a nuisance by the operators and deliberately removed, but the flip-up shield is easily lifted for inspection and maintenance and may be left in place. In a study initiated by the U.S. National Safety Council, random samples of older tractors with both types of shields were taken to see what proportion of shields were removed. Of 183tractors designed to have bolt-on shields, 35 had been removed. Of the 136 tractors with flip-up shields, 15 were removed. We wish to perform a test of H0:pb-pif versus Ha:pb≠pf where pb and pf are the proportions of all tractors with the bolt-on and flip-up shields removed, respectively. Which of the following conditions for performing the appropriate significance test is definitely not satisfied in this case?

(a) Both populations are Normally distributed.

(b) The data come from two independent samples.

(c) Both samples were chosen at random.

(d) The counts of successes and failures are large enough to use Normal calculations.

(e) Both populations are at least 10 times the corresponding sample sizes

45. Paying for college College financial aid offices expect students to use summer earnings to help pay for college. But how large are these earnings? One large university studied this question by asking a random sample of 1296students who had summer jobs how much they earned. The financial aid office separated the responses into two groups based on gender. Here are the data in summary form:

(a) How can you tell from the summary statistics that the distribution of earnings in each group is strongly skewed to the right? A graph of the data reveals no outliers. The use of two-sample t procedures is still justified. why?
(b) Construct and interpret a 90%confidence interval for the difference between the mean summer earnings of male and female students at this university.
(c) Interpret the 90%confidence level in the context of this study.

Explain why the conditions for using two-sample z procedures to perform inference about p1-p2are not met in the settings

In-line skatersA study of injuries to in-line skaters used data from the National Electronic Injury Surveillance System, which collects data from a random sample of hospital emergency rooms. The researchers interviewed 161 people who came to emergency rooms with injuries from in-line skating. Wrist injuries (mostly fractures) were the most common.6The interviews found that 53people were wearing wrist guards and 6of these had wrist injuries. Of the 108who did not wear wrist guards, 45had wrist injuries.

See all solutions

Recommended explanations on Math Textbooks

Statistics

Read Explanation

Applied Mathematics

Read Explanation

Mechanics Maths

Read Explanation

Logic and Functions

Read Explanation

Calculus

Read Explanation

Theoretical and Mathematical Physics

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