Introduction to the Practice of Statistics
Introduction to the Practice of Statistics
9th Edition
ISBN: 9781319013387
Author: David S. Moore, George P. McCabe, Bruce A. Craig
Publisher: W. H. Freeman
bartleby

Concept explainers

bartleby

Videos

Question
Book Icon
Chapter 11, Problem 25E

(a)

To determine

To find: The multiple regression for BMI using x1and x2 as explanatory variables.

(a)

Expert Solution
Check Mark

Answer to Problem 25E

Solution: The required multiple regression model is BMI=23.40.682x1+0.102x2_.

Explanation of Solution

Given: The data for the PA and BMI are given below:

Introduction to the Practice of Statistics, Chapter 11, Problem 25E , additional homework tip  1

Calculation: The explanatory variables are x1=(PA8.614)and x2=(PA8.614)2

To obtain multiple regression analysis by using Minitab, follow the steps below:

Step 1: Enter the data in Minitab worksheet.

Step 2: Go to Calc>Calculator.

Step 3: Enter x1=PA8.614 in Store result in variable for Expression.

Step 4: Click OK.

Step 5: Repeat the steps. Enter x2=(PA8.614)2 in Store result in variable for Expression.

Step 6: Go to Stat > Regression > Regression

Step 7: Select BMI in Response and select x1 and x2 in Predictors.

Step 8: Click OK.

The multiple regression model is obtained as BMI=23.40.682x1+0.102x2.

(b)

To determine

To find: The value of R2.

(b)

Expert Solution
Check Mark

Answer to Problem 25E

Solution: The value of R2 17.7%.

Explanation of Solution

It can be seen from part (b) that R2 is obtained as 17.7% which is explained by predictors x1 and x2. The percentage of R2 is very low. It indicates that the model is not good with this quadratic term.

(c)

To determine

To graph: The Normal quantile plot.

(c)

Expert Solution
Check Mark

Explanation of Solution

Graph: To perform the multiple regression by using year and census count as explanatory variables use Minitab. Follow the steps below:

Step 1: Enter the data in Minitab worksheet.

Step 2: Go to Stat> Regression >Regression.

Step 3: Select BMI in Response and select x1 and x2 in Predictors.

Step 4: Click on Graphs and select “Residuals versus fits.”

Step 5: Click OK.

The residual plot is obtained as:

Introduction to the Practice of Statistics, Chapter 11, Problem 25E , additional homework tip  2

Interpretation: From the obtained residual plot, it can be concluded that the plot represents no pattern and the data points are randomly scattered.

(d)

To determine

To test: The hypothesis that coefficient of the variable PA8.614 is equal to zero.

(d)

Expert Solution
Check Mark

Answer to Problem 25E

Solution: There is enough evidence to conclude that there is no linear increase over time.

Explanation of Solution

Calculation: From the output which is obtained in part (b), the regression equation is BMI=23.40.682x1+0.102x2. The standard error is 0.0555. From the equation, it can be seen that the coefficient of x2 is b2=0.102. To test the hypothesis that there is a linear rise over time, the null and alternative hypotheses can be stated as:

H0:β2=0Hα:β20

The level of significance is 0.05. The test statistic under null hypothesis is calculated as:

t=b2sb1=0.1020.05556=1.835

The p-value can be calculated as:

pvalue=2P(t|tcal|)=2P(t1.835)=2(0.034)=0.0678

The p-value is 0.0678.

Conclusion: The obtained p-value is greater than the significance level. Hence, there is enough evidence to conclude that the quadratic term contributes insignificantly to the fit.

Want to see more full solutions like this?

Subscribe now to access step-by-step solutions to millions of textbook problems written by subject matter experts!
Students have asked these similar questions
Homework Let X1, X2, Xn be a random sample from f(x;0) where f(x; 0) = (-), 0 < x < ∞,0 € R Using Basu's theorem, show that Y = min{X} and Z =Σ(XY) are indep. -
Homework Let X1, X2, Xn be a random sample from f(x; 0) where f(x; 0) = e−(2-0), 0 < x < ∞,0 € R Using Basu's theorem, show that Y = min{X} and Z =Σ(XY) are indep.
An Arts group holds a raffle.  Each raffle ticket costs $2 and the raffle consists of 2500 tickets.  The prize is a vacation worth $3,000.    a. Determine your expected value if you buy one ticket.     b. Determine your expected value if you buy five tickets.     How much will the Arts group gain or lose if they sell all the tickets?
Knowledge Booster
Background pattern image
Statistics
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, statistics and related others by exploring similar questions and additional content below.
Similar questions
SEE MORE QUESTIONS
Recommended textbooks for you
Text book image
MATLAB: An Introduction with Applications
Statistics
ISBN:9781119256830
Author:Amos Gilat
Publisher:John Wiley & Sons Inc
Text book image
Probability and Statistics for Engineering and th...
Statistics
ISBN:9781305251809
Author:Jay L. Devore
Publisher:Cengage Learning
Text book image
Statistics for The Behavioral Sciences (MindTap C...
Statistics
ISBN:9781305504912
Author:Frederick J Gravetter, Larry B. Wallnau
Publisher:Cengage Learning
Text book image
Elementary Statistics: Picturing the World (7th E...
Statistics
ISBN:9780134683416
Author:Ron Larson, Betsy Farber
Publisher:PEARSON
Text book image
The Basic Practice of Statistics
Statistics
ISBN:9781319042578
Author:David S. Moore, William I. Notz, Michael A. Fligner
Publisher:W. H. Freeman
Text book image
Introduction to the Practice of Statistics
Statistics
ISBN:9781319013387
Author:David S. Moore, George P. McCabe, Bruce A. Craig
Publisher:W. H. Freeman
Points, Lines, Planes, Segments, & Rays - Collinear vs Coplanar Points - Geometry; Author: The Organic Chemistry Tutor;https://www.youtube.com/watch?v=dDWjhRfBsKM;License: Standard YouTube License, CC-BY
Naming Points, Lines, and Planes; Author: Florida PASS Program;https://www.youtube.com/watch?v=F-LxiLSSaLg;License: Standard YouTube License, CC-BY