In statistics a bias is systematicÊasÊopposedÊtoÊaÊrandomÊdistortion ofÊaÊstatisticÊasÊaÊresultÊofÊsamplingÊprocedure. It is a vital skill to identify a bias because represent distortion of data.

To prevent bias

Official statistics are more likely to be correct and upto date, however because it is government controlled they maybe bias or not showwing the simple data.

Confirmation Bias

Herbert I. Weisberg has written:

'Bias and causation' -- subject(s): Discriminant analysis, Paired comparisons (Statistics)