The width of the confidence interval estimate of the population mean μ is a function of only two quantities: the population standard deviation σ and the sample size n.

Confidence Interval

A range of values, derived from sample statistics, that is believed to contain the value of an unknown population parameter at a certain confidence level.

Population Standard Deviation

A measure of the dispersion or variability of a set of data points in a population.

Sample Size

The number of observations or elements selected from a population for the purpose of statistical analysis.