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Chapter 8: Q.10 (page 482)

How confident? The figure at top right shows the result of taking 25SRSs from a Normal population and constructing a confidence interval for each sample. Which confidence level—80%,90%,95%, or 99%—do you think was used? Explain.

Short Answer

Expert verified

The nearest confidence level is 99%.

Step by step solution

01

Given Information

The result of taking 25 SRSs:

02

Explanation

The red lines under the curve represent the sample means that do not contain the true population proportion.

We note that there are 0out of the 25samples that do not contain the true proportion and thus 25out of the 25samples contain the true proportion:

2525=1=100%

The nearest confidence level is 99%(although 95%could also be a possible used confidence level).

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