A simple random sample of size n is drawn from a normally distributed population, and the mean of the sample is (x with a line o
ver it), while the standard deviation is s. What is the 99% confidence interval for the population mean? Use the table below to help you answer the question. Confidence Level. 90%. 95%. 99%
z*-score. 1.645. 1.96. 2.58
If we extract a sample of size n from a normal population and we want to estimate the population mean then the confidence interval for the mean will be:
Where
Where is an estimator for the mean μ.
n is the sample size and s is its standard deviation.
is the level of significance
= 1-Confidence Level
Then
Then the 99% confidence interval for the population mean is