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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extrapolation

  1. [statistics] Using known or observed data to infer or calculate values for unobserved times, locations or other variables outside a sampled area. In the absence of data, extrapolation is a common method for making predictions, but it is not always accurate. For example, based on observed economic indicators, an economist can make predictions about the state of the economy at a future time. These predictions may not be accurate because they cannot take into account seemingly random events such as natural disasters.