Editing Selection bias (section)

===Data===
* Partitioning (dividing) data with knowledge of the contents of the partitions, and then analyzing them with tests designed for blindly chosen partitions.
*[[Post hoc analysis|Post hoc]] alteration of data inclusion based on arbitrary or subjective reasons, including:
**[[Cherry picking (fallacy)|Cherry picking]], which actually is not selection bias, but [[confirmation bias]], when specific subsets of data are chosen to support a conclusion (e.g. citing examples of plane crashes as evidence of airline flight being unsafe, while ignoring the far more common example of flights that complete safely. See: [[availability heuristic]])
**Rejection of bad data on (1) arbitrary grounds, instead of according to previously stated or generally agreed criteria or (2) discarding "[[outlier]]s" on statistical grounds that fail to take into account important information that could be derived from "wild" observations.<ref name="Kruskal1960">{{cite journal|last1=Kruskal|first1=William H.|title=Some Remarks on Wild Observations|journal=Technometrics|volume=2|issue=1|year=1960|pages=1–3|doi=10.1080/00401706.1960.10489875|url=http://www.tufts.edu/~gdallal/out.htm|url-access=subscription}}</ref>