Bias

1. an error in experimental measurement OR

2. the effect of an error in the model.

In the former case, bias is a constant error, not subject to random fluctuation, e.g., a zero offset on a meter. In the latter case, the error is between the chosen model and the true physical situation.

Bias is often used to describe the error caused by assuming a linear model when the true physical situation is nonlinear. The computation of bias requires both a current model and a model postulated or known to be the "true" model.

See also

Gage Bias

Alias

Confounding.

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