1Cademy - Mathematical Definition of Estimator Bias

Function A: Calculates the arithmetic average of the five data points.
Function B: Identifies the middle value after sorting the data points.

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Point Estimators

Formula

Mathematical Definition of Estimator Bias

$\mathrm{bias}(\hat{\theta}_m) = \mathbb{E}(\hat{\theta}_m) - \theta$ , where $\hat{\theta}_m$ is the estimator of a parameter, $\theta$ is the true value of that parameter, and $m$ is the sample size/number of data points. The bias of an estimator for a parameter is the difference between the expected value that the estimator will take when trained on data and the actual value of the parameter used to generate the data.