Find study content
Learning Materials

Discover learning materials by subject, university or textbook.

Explanations

Textbooks

Exams
All Subjects

Anthropology

Archaeology

Architecture

Art and Design

Bengali

Biology

Business Studies

Greek

Chemistry

Chinese

Combined Science

Computer Science

Economics

Engineering

English

English Literature

Environmental Science

French

Geography

German

History

Hospitality and Tourism

Human Geography

Italian

Japanese

Law

Macroeconomics

Marketing

Math

Media Studies

Medicine

Microeconomics

Music

Nursing

Nutrition and Food Science

Physics

Polish

Politics

Psychology

Religious Studies

Sociology

Spanish

Sports Sciences

Translation

All Subjects

Biology

Business Studies

Chemistry

Combined Science

Computer Science

Economics

English

Environmental Science

Geography

History

Math

Physics

Psychology

Sociology

EXAM TYPES

GCSE

IGCSE

AS

A Level

International A Level

University Admissions Tests

GCSE SUBJECTS

GCSE 1

GCSE 2

GCSE 3

GCSE 4

GCSE 5

SOME-TEXT

IGCSE SUBJECTS

IGCSE 1

AS SUBJECTS

AS 1

A Level SUBJECTS

A Level 1

International A Level SUBJECTS

International A Level 1

University Admissions Tests SUBJECTS

University Admissions Tests 1
Features
Features

Discover all of these amazing features with a free account.

Flashcards

Vaia AI

Notes

Study Plans

Study Sets
What’s new?

Flashcards
Study your flashcards with three learning modes.

Study Sets
All of your learning materials stored in one place.

Notes
Create and edit notes or documents.

Study Plans
Organise your studies and prepare for exams.
Resources
Discover

All the hacks around your studies and career - in one place.

Find a job

Find a degree

Student Deals

Magazine

Mobile App
Featured

Magazine
Trusted advice for anyone who wants to ace their studies & career.

Job Board
The largest student job board with the most exciting opportunities.

Vaia Deals
Verified student deals from top brands.

Our App
Discover our mobile app to take your studies anywhere.

Go to App

Learning Materials

Features

Discover

Introductory Statistics

Barbara Illowsky, Susan Dean

$Math Studyset Vaia Explanations$ Math

OER 2018 Edition · 902 pages

ISBN: 9781938168208

Chapter 8: Q.2 (page 477)

In words, define the random variables $X$ and $\bar{X}$ .

Short Answer

Expert verified

The sample mean, $\bar{x}$ is the point estimate for the population mean $μ$ .

Step by step solution

01

Given Information

The random variables are $X$ and $\bar{X}$ .

02

Explanation

The sample mean, $\bar{x}$ is the point estimate for the population mean $μ$ .

Suppose that $X_{1}, X_{2}, \dots, X_{n}$ , is a random sample from a normal distribution with unknown mean $μ$ , than test statistic

$\bar{X} = \frac{X_{1} + X_{2} + \dots + X_{n}}{n},$

is normally distributed with mean $μ$ and variance localid="1648836325806" $σ^{2} / n$ .

03

Explanation

It is often necessary to construct confidence intervals on a population proportion. For example, suppose that a random sample of size $n$ has been taken from a large (possibly infinite) population and that $X (\leq n)$ observations in this sample belong to a class of interest. Then

\bar{P} = \frac{X}{n}

is a point estimator of the proportion of the population $p$ that belongs to this class.

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

Define the random variables $X$ and $P'$ in words.

The mean age for all Foothill College students for a recent Fall term was $33.2$ . The population standard deviation has been pretty consistent at $15$ . Suppose that twenty-five Winter students were randomly selected. The mean age for the sample was $30.4$ . We are interested in the true mean age for Winter Foothill College students. Let $X =$ the age of a Winter Foothill College student.

In words, define the random variable $\bar{X}$ .

A random sample of statistics students were asked to estimate the total number of hours they spend watching television in an average week. The responses are recorded in Table $8.4$ . Use this sample data to construct a $98$ % confidence interval for the mean number of hours statistics students will spend watching television in one week.

$0$	$3$	$1$	$20$	$9$
$5$	$10$	$1$	$10$	$4$
$14$	$2$	$4$	$4$	$5$

Table $8.4$

Fill in the blanks on the graph with the areas, upper and lower limits of the confidence interval, and the sample mean.

Using the same mean, standard deviation, and sample size, how would the error bound change if the confidence level were reduced to 90%? Why?

See all solutions

Recommended explanations on Math Textbooks

Pure Maths

Read Explanation

Discrete Mathematics

Read Explanation

Applied Mathematics

Read Explanation

Mechanics Maths

Read Explanation

Geometry

Read Explanation

Probability and Statistics

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