/*! 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.14 Smartphone Ownership. Refer to P... [FREE SOLUTION] | 91影视

91影视

Log out

Learning Materials

Features

Discover

Chapter 11: Q.14 (page 480)

Smartphone Ownership. Refer to Problem 13 .

a. Find a 99% confidence interval for the difference, p1-p2, between the proportions of men and women smartphone owners.

b. Interpret your answer in part (a) in terms of the difference in percentages of men and women smartphone owners.

Short Answer

Expert verified

a). The gap in the proportion of men and women who own smartphones is somewhere between 0.0062and 0.1142, according to 99%confidence.

b). One can be 99%certain that the gap in smartphone ownership between men and women is between 0.62%and 11.42%.

Step by step solution

01

Part (a) Step 1: Given Information

Population 1Men: role="math" localid="1651421541742" n1=1029,

x1=607.

Population 1Women: n2=1223,

x2=648.

02

Part (a) Step 2: Explanation

A significance level of 伪,

To find z伪/2using table II.

Significance level is 1%.

i.e. 伪=0.01.

Using table II,

z伪/2=z0.01/2

=z0.005

=2.58.

The endpoints for the confidence interval of p1-p2are -

p^1-p^2卤z伪/2路p^11-p^1n1+p^21-p^2n2鈬�CI=(0.590-0.5298)卤2.580.590(1-0.590)1029+0.5298(1-0.5298)1223鈬�CI=0.0602卤(2.58脳0.209)

鈬�CI=0.0602卤0.0540

鈬�CI=0.0062to0.1142

03

Part (b) Step 2: Given Information

Population 1Men: n1=1029,

x1=607.

Population 1Women: n2=1223,

x2=648.

04

Part (b) Step 2: Explanation

The endpoints for the confidence interval of p1-p2are -

p^1-p^2卤z伪/2路p^11-p^1n1+p^21-p^2n2

鈬�CI=0.0062to0.1142

鈬�CI=0.62%to11.42%

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

In a New York Times article "More Mother Breast-Feed, in First Months at Least," G. Harris reported that 779new mothers breast-feed their infants at least briefly, the highest rate seen in the United States in more than a decade. His report was based on data for 434 infants from the National Health and Nutrition Examination Survey, which involved in-person interviews and physical examinations. Find a 90% confidence interval for the percentage of all new mothers who breast-feed their infants at least briefly.

Indicted Governor. On Thursday, June 13, 1996, thenArizona Governor Fife Symington was indicted on 23counts of fraud and extortion. Just hours after the federal prosecutors announced the indictment, several polls were conducted of Arizonans asking whether they thought Symington should resign. A poll conducted by Research 91影视, Inc., that appeared in the Phoenix Gazette, revealed that 58%of Arizonans felt that Symington should resign; it had a margin of error of plus or minus 4.9 percentage points. Another poll, conducted by Phoenix-based Behavior Research Center and appearing in the Tempe Daily News, reported that 54% of Arizonans felt that Symington should resign; it had a margin of error of plus or minus 4.4 percentage points. Can the conclusions of both polls be correct? Explain your answer.

In this Exercise, we have given the number of successes and the sample size for a simple random sample from a population. In each case,

a. use the one-proportion plus-four z-interval procedure to find the required confidence interval.

b. compare your result with the corresponding confidence interval found in Exercise 11.25-11.30, if finding such a confidence interval was appropriate.

role="math" localid="1651325715651" x=8,n=40,95%level

11.94 Drowning Deaths. In the article "Drowning Deaths of Zero to Five Year Old Children in Victorian Dams, 1989-2001" (Australian Journal of Rural Health, Vol. 13, Issue 5, pp. 300-308), L. Bugeja and R. Franklin examined drowning deaths of young children in Victorian dams to identify common contributing factors and develop strategies for future prevention. Of 11young children who drowned in Victorian dams located on farms, 5 were girls, At the 5% significance level, do the data provide sufficient evidence to conclude that, of all young children drowning in Victorian dams located on farms, less than half are girls?

Obtain a sample size that will ensure a margin of error of at most the one specified.

Margin of error=0.04

Confidence level=99%
See all solutions

Recommended explanations on Math Textbooks

Calculus

Read Explanation

Statistics

Read Explanation

Mechanics Maths

Read Explanation

Theoretical and Mathematical Physics

Read Explanation

Geometry

Read Explanation

Decision Maths

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.