Question

What does the 95% represent in a 95% confidence interval?

Choose the correct answer below
A. The 95% represents the probability the interval will contain the parameter (for example, the population mean or population proportion).
B. The 95% represents the proportion of intervals that will not contain the parameter (for example, the population mean or population proportion) If a large number of different samples is obtained
C. The 98% represents the probability the interval will not contain the parameter (for example, the population mean or population proportion)
D. The 95% represents the proportion of intervals that would contain the parameter (for example, the population mean or population proportion) If a large number of different samples is obtained

Answer 1

The correct answer is A.

The 95% represents the probability the interval will contain the parameter (for example, the population mean or population proportion) if the same sampling procedure is repeated many times and a new confidence interval is calculated each time. In other words, if we construct 100 confidence intervals using the same sample size and level of confidence, we would expect 95 of them to contain the true parameter and 5 of them to not contain it.

Note that this statement does not guarantee that the true parameter is within the interval with a probability of 0.95, but rather that the method used to construct the interval has a 95% success rate in capturing the true parameter, assuming certain assumptions are met.

Explanation: