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Chapter 6: Q66E (page 363)

If nothing is known about p, .5 can be substituted for p in the sample size formula for a population proportion. But when this is done, the resulting sample size may be larger than needed. Under what circumstances will be using p = .5 in the sample size formula yield a sample size larger than needed to construct a confidence interval for p with a specified bound and a specified confidence level?

Short Answer

Expert verified

Whenever p is greater than 0.5

Step by step solution

01

Given information

If nothing is known regarding p, 0.5 can be used in the sample size formula for a percentage of the population instead of p. However, the final sampling size may be greater than necessary if this is done.

02

Explanation

When p = 0.5, the sample size required is at its greatest.

As a result, if p is equivalent to 0.5, p=0.5, The sample size calculation will provide the needed sample size. However, if p is more than 0.5, use p=0.5. The sample size formula will provide a sample size more than what is needed to generate a confidence interval for p with a particular limit as well as a level of confidence.

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Most popular questions from this chapter

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