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Chapter 10: Q. 89 (page 688)

Music and memory Refer to Exercise 87.

a. Construct and interpret a 99%confidence interval for the true mean difference. If you already defined the parameter and checked conditions in Exercise87, you don鈥檛 need to do them again here.

b. Explain how the confidence interval provides more information than the test in Exercise .

Short Answer

Expert verified

a. 99%confidence interval for the true mean difference is 0.2114,2.9286.

b. The confidence interval gives us the range of possible values for the true mean difference than the significance test.

Step by step solution

01

Part (a): Step 1: Given information

We need to Construct and interpret a 99%confidence interval for the true mean difference.

02

Part (a): Step 2: Explanation

Given:

n=Samplesize=30x炉d=Meandifferences=1.57sd=Standarddeviationofdifferences=2.70c=confidencelevel=99%=0.99

Now we will determine the confidence interval for the population mean difference.

Now at Degree of freedom

=29andc=99%t伪2=2.756Themarginoferroris:E=t伪2脳sdn=2.756脳2.7030鈮�1.3586Nowtheboundariesofconfidenceintervalwillbecomex炉d-E=1.57-1.3586=0.2114x炉d+E=1.57+1.3586=2.9286Confidenceintervalis0.2114,2.9286
03

Part (b): Step 1: Given information

We need to explain how the confidence interval provides more information than the test.

04

Part (b): Step 2: Explanation

The confidence interval gives us more information than the significance test because the confidence interval gives us a different range of possible values for true mean difference than the significance test because the significance test checks only one possible value for the true mean difference.

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Most popular questions from this chapter

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