An estimator involves using data from a sample to infer values for an unknown population parameter (for example the population mean).

Biasedness

The biasedness of an estimator refers to the difference between the true value of the population parameter and the expected value of the estimator. Better estimators have smaller values of biasedness.

The biasedness of an estimator for a parameter can be calculated as

Estimators where are said to be "unbiased estimators".

Quality

The quality of an estimator can be determined as the loss function between the estimator of the parameter and the parameter.

Types

• Interval Estimator
• Point Estimator