Estimating a population mean

A confidence interval for a mean estimates a population mean based on the results from a sample. Go through this tutorial to learn how to calculate confidence intervals using sample mean and sample standard deviation.

Introduction to t statistics

Simulation showing value of t statistic

Conditions for valid t intervals

Conditions for a t interval for a mean

Example finding critical t value

Finding the critical value t* for a desired confidence level

Example constructing a t interval for a mean

Calculating a t interval for a mean

Confidence interval for a mean with paired data

Sample size for a given margin of error for a mean

Sample size and margin of error in a confidence interval for a mean