After constructing a confidence interval estimate for a population mean, you believe that the interval is useless because it is
1 answer:
Answer:
a. increase the sample size
Step-by-step explanation:
The width of a confidence interval is twice the margin of error, which is given by:
In which is the standrd deviation of the population, n is the size of the sample, and z is the confidence coefficient(the higher the confidence level, the higher z is).
The only of those variables which is direct proportional to M is the sample size. This means that if we want to decrease the width of M, we need to increase the sample size.
So the correct answer is:
a. increase the sample size
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