GIS Dictionary

Definitions for GIS terms related to operations such as analysis, GIS modeling and web-based GIS, cartography, and Esri software.

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precision

See Also: accuracy, dataset precision, double precision, single precision

  1. [data quality] The closeness of a repeated set of observations of the same quantity to one another. Precision is a measure of the control over random error. For example, assessment of the quality of a surveyor's work is based in part on the precision of their measured values.
  2. [data quality] The number of significant digits used to store numbers, particularly coordinate values. Precision is important for accurate feature representation, analysis, and mapping.
  3. [data quality] A statistical measure of repeatability, usually expressed as the variance of repeated measures about the mean.