## What is the difference between an estimate and an estimator?

## Answer

These two terms are related. An estimator is a rule or formula used to create estimates.

For example, a common estimator for the population mean is \(\bar{x} = \frac{\sum_{i=1}^n x_i}{n}\). If you had a sample consisting of the numbers 1 to 5, then you could use the above formula to get an estimate of 3. It is important to remember that while an estimate is just a single number, an estimator is a random variable with its own sampling distribution.