GIS Dictionary
Definitions for GIS terms related to operations such as analysis, GIS modeling and web-based GIS, cartography, and Esri software.
Now available for purchase: A to Z GIS: An illustrated dictionary of geographic information systems.
Search the GIS Dictionary:
GIS Bibliography
Researching GIS?
Search the GIS Bibliography for a vast index of books, journals, conference proceedings and reports.
standard deviation
-
[statistics]
A statistical measure of the spread of values from their mean, calculated as the square root of the sum of the squared deviations from the mean value, divided by the number of elements minus one. The standard deviation for a distribution is the square root of the variance.