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Question 6.17: Refer to Example 6.16. Find the sample size needed so that t......

Refer to Example 6.16. Find the sample size needed so that the power will be at least 0.9.

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Script File

The following computer output (from MINITAB) presents the solution:

Power and Sample Size
1-Sample t Test
Testing mean = null (versus > null)
Calculating power for mean = null + difference
Alpha = 0.05 Assumed standard deviation = 1.5
Sample Target
Difference Size Power Actual Power
2 7 0.9 0.926750

   The smallest sample size for which the power is 0.9 or more is 7. The actual power is 0.927.

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