Poistumat

Poistumat is a Finnish noun referring to the act or result of removing something or someone from a system, group, or dataset. The term is used in statistics, demography, and data management, but may appear in other contexts as well. It derives from the verb poistua (to depart, disappear) and the related noun poistuma; the plural form is poistumat.

In statistics and research, poistumat describes items that have left the sample or population at risk during a given period. This includes participants who drop out of a longitudinal study, individuals who migrate or die, or records that are excluded during data cleaning. The concept is closely linked to attrition and censoring, and its rate affects the interpretation of results and the handling of missing data.

In forestry and natural resource statistics, poistumat can refer to the reduction of a stock due to harvest, natural mortality, or damage. In population accounting, it may denote removals from the resident population, such as emigration or death.

Handling of poistumat involves reporting their size, reasons, and timing, and using methods appropriate for censored data or population at risk. Researchers consider poistumat as part of data quality, cohort maintenance, and resource planning in field operations.

Note on usage: Poistumat is a Finnish term, and its precise meaning and usage can vary between disciplines and organizations. In non-Finnish contexts, equivalents include attrition, removal, deletion, or censoring, depending on the field.