The winner of the 2012-2013 National Basketball Association (NBA) championship was the Miami Heat. One possible starting lineup for that team is as follows.

a. Determine the population mean height, μ, of the five players:

b. Consider samples of size 2without replacement. Use your answer to Exercise 7.11(b)on page 295and Definition 3.11on page 140to find the mean, μr, of the variable x^.

c. Find μx*using only the result of part (a).

Short Answer

Expert verified
  1. The population mean height of the players is 78.6.
  2. The mean height μx¯for sample of size 2is 78.6.
  3. The mean height μx¯for sample size 2is equal to the population mean height of the players that is78.6.

Step by step solution

01

Part (a) Step 1: Given information

Given in the question that a table

02

Part (a) Step 2: Explanation

Here we need to find the population mean height of the players

The equation will be

μ=i=1nxin=83+76+80+74+805=3935=78.6

Therefore the population mean height of the players will be78.6

03

Part (b) Step 1: Given information

Given in the question that a table

04

Part (b) Step 2: Explanation

Here we need to obtain the mean height μx¯for sample size 2

The below table shows the corresponding mean obtained

Sample sizeHeightMean(x¯)B,W83,7683+762=79.5B,J83,8083+802=81.5B,C83,7483+742=78.5B,H83,8083+802=81.5W,J76,8076+802=78.0W,C76,7476+742=75.0W,H76,8076+802=78.0J,C80,7480+742=77.0J,H80,8080+802=80.0C,H74,8074+802=77.0

The mean of all possible sample mean is get in the table is

μx¯=xi¯N=79.5+81.5+78.5+81.5+78.0+75.0+78.0+77.0+80.0+77.010=78610=78.6

05

Part (c) Step 1: Given information

Given in the question that a table

06

Part (c) Step 2: Explanation 

Here we need to compare the population mean and mean height that has sample size 2.

So, the mean of the sample mean is equal to the population mean

μx=μ=78.6

So, here both are same.

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 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

Suppose that a random sample of size 1is to be taken from a finite population of size N.

a. How many possible samples are there?

b. Identify the relationship between the possible sample means and the possible observations of the variable under consideration.

c. What is the difference between taking a random sample of size 1from a population and selecting a member at random from the population?

Alcohol consumption on college and university campuses has gained attention because undergraduate students drink significantly more than young adults who are not students. Researchers I. Balodis et al. studied binge drinking in undergraduates in the article "Binge Drinking in Undergraduates: Relationships with Gender, Drinking Behaviors, Impulsivity, and the Perceived Effects of Alcohol". The researchers found that students who are binge drinkers drink many times a month with the span of each outing having a mean of 4.9 hours and a standard deviation of 1.1 hours.

Part (a): For samples of size 40, find the mean and standard deviation of all possible sample mean spans of binge drinking episodes. Interpret your results in words.

Part (b): Repeat part (a) with n=120.

A variable of a population has mean μand standard deviation σFor a large sample size n, fill in the blanks, Justify your answers.

a. Approximately _ %of all possible samples have means within σ/nof the population mean, μ.

b. Approximately _ %of all possible samples have means within 2σ/nof the population mean, μ

c. Approximately _ %of all possible samples have means within 3σ/nof the population mean, μ

d. Approximately __ %of all possible samples have means within zv/2of the population mean, μ

7.54 Unbiased and Biased Estimators. A statistic is said to be an unbiased estimator of a parameter if the mean of all its possible values equals the parameter. otherwise, it is said to be a biased estimator. An unbiased estimator yields, on average, the correct value of the parameter, whereas a biased estimator does not.
a. Is the sample mean an unbiased estimator of the population mean? Explain your answer.
b. Is the sample median an unbiased estimator of the population median? (Hint: Refer to Example 7.2 on pages 292-293. Consider samples of size 2.)

Why is obtaining the mean and standard deviation of x¯ a first step in approximating the sample distribution of the sample mean by a normal distribution?

See all solutions

Recommended explanations on Math Textbooks

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