Estimating a population mean

The most commonly estimated parameter for numerical data is the population mean, µ. We now examine how to estimate µ when the population standard deviation, σ, is a known value.

In most practical situations, the population standard deviation, σ, is also unknown and must be estimated. However we leave this type of problem until later in this section.

Confidence interval from standard error

A 95% confidence interval for µ is based on the formula for the sample mean's standard error.

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