Essential Statistics
Essential Statistics
2nd Edition
ISBN: 9781259570643
Author: Navidi
Publisher: MCG
Question
Book Icon
Chapter 9.3, Problem 10E

a.

To determine

Compute the differences in samples of matched pairs Sample-1– Sample-2.

a.

Expert Solution
Check Mark

Answer to Problem 10E

The differences in samples of matched pairs Sample-1– Sample-2 is,

S.noDifference
1–6
2–1
3–9
4–1
5–5
6–1
7–4
8–8
9–2
10–9

Explanation of Solution

Calculation:

The data represents the sample of a five matched pairs.

Let μd=μ1μ2 where μ1 be the population mean-1 is and μ2 be the population mean-2.

The differences in samples of matched pairs Sample-1– Sample-2 is,

S.noSample-1Sample-2Difference=Sample1Sample2
128342834=6
229302930=1
322312231=9
425262526=1
526312631=5
629302930=1
727312731=4
824322432=8
927292729=2
1028372837=9

b.

To determine

Find the value of t-test statistic.

b.

Expert Solution
Check Mark

Answer to Problem 10E

The value of test statistic is –4.3948.

Explanation of Solution

Calculation:

The test hypotheses are given below:

Null hypothesis:

H0:μd=0

That is, there is no significant difference between the population mean1 and population mean2.

Alternate hypothesis:

H1:μd0

That is, there is a significant difference between the population mean1 and population mean2.

Mean and standard deviation of differences:

Software procedure:

Step-by-step procedure to obtain the mean and standard deviation using the MINITAB software:

  • Choose Stat > Basic statistic > Display descriptive statistics.
  • In Variables, enter the column of Differences.
  • In Statistics, select mean, standard deviation and N total.
  • Click OK.

Output using the MINITAB software is given below:

Essential Statistics, Chapter 9.3, Problem 10E , additional homework tip  1

From the MINITAB output, the mean and standard deviation are –4.6 and 3.31.

The mean and standard deviation of the differences is –4.6 and 3.31.

The test statistic is obtained as follows,

t=d¯0(sdn)=4.60(3.3110)=4.61.0467=4.3948

Thus, the test statistic is –4.3948.

c.

To determine

Check whether the null hypothesis is rejected at α=0.05 level of significance.

c.

Expert Solution
Check Mark

Answer to Problem 10E

There is enough evidence to reject the null hypothesis H0 at α=0.05 level of significance.

Explanation of Solution

Degrees of freedom:

The degrees of freedom for the test statistic is,

d.f=n1=101=9

Thus, the degree of freedom is 9.

P-value:

Software procedure:

Step-by-step procedure to obtain the P-value using the MINITAB software:

  • Choose Graph > Probability Distribution Plot.
  • Choose View Probability > OK.
  • From Distribution, choose ‘t’ distribution.
  • In Degrees of freedom, enter 9.
  • Click the Shaded Area tab.
  • Choose X value and Both Tail for the region of the curve to shade.
  • In X-value enter –4.3948.
  • Click OK.

Output using the MINITAB software is given below:

Essential Statistics, Chapter 9.3, Problem 10E , additional homework tip  2

From the MINITAB output, the P-value is 2×0.0008667=0.0017 .

Thus, the P-value is 0.0017.

Decision rule based on P-value:

If Pvalueα, then reject the null hypothesis H0.

If Pvalue>α, then fail to reject the null hypothesis H0.

Here, the level of significance is α=0.05.

Conclusion based on P-value approach:

The P-value is 0.0017 and α value is 0.05.

Here, P-value is less than the α value.

That is, 0.0017(=Pvalue)<0.05(=α).

By the rejection rule, reject the null hypothesis.

Thus, there is enough evidence to reject the null hypothesis H0.

d.

To determine

Check whether the null hypothesis is rejected at α=0.01 level of significance.

d.

Expert Solution
Check Mark

Answer to Problem 10E

There is enough evidence to reject the null hypothesis H0 at α=0.01 level of significance.

Explanation of Solution

From part (c), the P-value is 0.0017.

Decision rule based on P-value:

If Pvalueα, then reject the null hypothesis H0.

If Pvalue>α, then fail to reject the null hypothesis H0.

Here, the level of significance is α=0.01.

Conclusion based on P-value approach:

The P-value is 0.0017 and α value is 0.01.

Here, P-value is less than the α value.

That is, 0.0017(=Pvalue)<0.01(=α).

By the rejection rule, reject the null hypothesis.

Thus, there is enough evidence to reject the null hypothesis H0.

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!

Chapter 9 Solutions

Essential Statistics

Ch. 9.1 - Prob. 11ECh. 9.1 - Prob. 12ECh. 9.1 - Prob. 13ECh. 9.1 - Prob. 14ECh. 9.1 - Prob. 15ECh. 9.1 - Prob. 16ECh. 9.1 - Prob. 17ECh. 9.1 - Prob. 18ECh. 9.1 - Prob. 19ECh. 9.1 - Prob. 20ECh. 9.1 - Prob. 21ECh. 9.1 - Prob. 22ECh. 9.1 - Prob. 23ECh. 9.1 - Prob. 24ECh. 9.1 - Prob. 25ECh. 9.1 - Prob. 26ECh. 9.1 - 27. Does this diet help? A group of 78 people...Ch. 9.1 - Prob. 28ECh. 9.1 - Prob. 29ECh. 9.1 - Prob. 30ECh. 9.1 - Prob. 31ECh. 9.1 - Prob. 32ECh. 9.1 - Prob. 33ECh. 9.1 - Prob. 34ECh. 9.1 - Prob. 35ECh. 9.1 - Prob. 36ECh. 9.1 - Prob. 37ECh. 9.1 - 38. Interpret calculator display: The following...Ch. 9.1 - Prob. 39ECh. 9.1 - Prob. 40ECh. 9.1 - Prob. 41ECh. 9.2 - Prob. 1CYUCh. 9.2 - Prob. 2CYUCh. 9.2 - Prob. 3CYUCh. 9.2 - Prob. 4CYUCh. 9.2 - Prob. 5ECh. 9.2 - Prob. 6ECh. 9.2 - Prob. 7ECh. 9.2 - Prob. 8ECh. 9.2 - Prob. 9ECh. 9.2 - Prob. 10ECh. 9.2 - Prob. 11ECh. 9.2 - Prob. 12ECh. 9.2 - Prob. 13ECh. 9.2 - Prob. 14ECh. 9.2 - Prob. 15ECh. 9.2 - Prob. 16ECh. 9.2 - Prob. 17ECh. 9.2 - Prob. 18ECh. 9.2 - Prob. 19ECh. 9.2 - Prob. 20ECh. 9.2 - Prob. 21ECh. 9.2 - Prob. 22ECh. 9.2 - Prob. 23ECh. 9.2 - Prob. 24ECh. 9.2 - Prob. 25ECh. 9.2 - Prob. 26ECh. 9.2 - Prob. 27ECh. 9.2 - Prob. 28ECh. 9.2 - Prob. 29ECh. 9.2 - Prob. 30ECh. 9.2 - Prob. 31ECh. 9.2 - Prob. 32ECh. 9.2 - Prob. 33ECh. 9.2 - Prob. 34ECh. 9.2 - Prob. 35ECh. 9.2 - Prob. 36ECh. 9.2 - Prob. 37ECh. 9.3 - Prob. 1CYUCh. 9.3 - Prob. 2CYUCh. 9.3 - Prob. 3CYUCh. 9.3 - Prob. 4CYUCh. 9.3 - Prob. 5ECh. 9.3 - Prob. 6ECh. 9.3 - Prob. 7ECh. 9.3 - Prob. 8ECh. 9.3 - Prob. 9ECh. 9.3 - Prob. 10ECh. 9.3 - Prob. 11ECh. 9.3 - Prob. 12ECh. 9.3 - Prob. 13ECh. 9.3 - Prob. 14ECh. 9.3 - Prob. 15ECh. 9.3 - SAT coaching: A sample of 32 students took a class...Ch. 9.3 - Prob. 17ECh. 9.3 - Prob. 18ECh. 9.3 - Prob. 19ECh. 9.3 - Tires and fuel economy: A tire manufacturer is...Ch. 9.3 - Prob. 21ECh. 9.3 - Prob. 22ECh. 9.3 - Prob. 23ECh. 9.3 - Prob. 24ECh. 9.3 - Prob. 25ECh. 9.3 - Prob. 26ECh. 9.3 - Prob. 27ECh. 9.3 - Prob. 28ECh. 9.3 - Prob. 29ECh. 9.3 - Prob. 30ECh. 9.3 - Advantage of matched pairs: Refer to Exercise...Ch. 9.3 - Prob. 32ECh. 9 - A sample of 15 weight litters is tested to see how...Ch. 9 - Prob. 2CQCh. 9 - Prob. 3CQCh. 9 - Prob. 4CQCh. 9 - Prob. 5CQCh. 9 - Prob. 6CQCh. 9 - Prob. 7CQCh. 9 - Prob. 8CQCh. 9 - Prob. 9CQCh. 9 - Prob. 10CQCh. 9 - Prob. 11CQCh. 9 - In a survey of 300 randomly selected female and...Ch. 9 - Prob. 13CQCh. 9 - Prob. 14CQCh. 9 - Prob. 15CQCh. 9 - Prob. 1RECh. 9 - Prob. 2RECh. 9 - Prob. 3RECh. 9 - Prob. 4RECh. 9 - Prob. 5RECh. 9 - Prob. 6RECh. 9 - Prob. 7RECh. 9 - Prob. 8RECh. 9 - Prob. 9RECh. 9 - Polling results: A simple random sample of 400...Ch. 9 - Treating bean plants: In a study to measure the...Ch. 9 - Prob. 12RECh. 9 - Prob. 13RECh. 9 - Prob. 14RECh. 9 - Prob. 15RECh. 9 - Prob. 1WAICh. 9 - Prob. 2WAICh. 9 - Describe the differences between performing a...Ch. 9 - Prob. 4WAICh. 9 - In what ways is the procedure for constructing a...Ch. 9 - Prob. 6WAICh. 9 - Prob. 7WAICh. 9 - Prob. 1CSCh. 9 - Prob. 2CSCh. 9 - Prob. 3CSCh. 9 - Prob. 4CSCh. 9 - Prob. 5CSCh. 9 - Prob. 6CS
Knowledge Booster
Background pattern image
Recommended textbooks for you
Text book image
Glencoe Algebra 1, Student Edition, 9780079039897...
Algebra
ISBN:9780079039897
Author:Carter
Publisher:McGraw Hill