Forecast Bias

Forecast Bias is a systematic skew in a forecast (consistently too conservative or consistently too optimistic) as opposed to ordinary, random miss. A single missed forecast could be noise; a team that’s off by the same direction and rough magnitude quarter after quarter has a bias, not bad luck.

Bias only becomes visible once forecast accuracy is tracked against actuals over multiple periods, department by department, rather than judged one period at a time. See how a reconciled actuals history makes it measurable in forecast bias and sandbagging.