I need to explain why ArcGIS offers the function "standard deviation" when symbolizing rasters with the Stretch method.
The Standard Deviation is a measure of how spread out numbers are and is calculated by the square root of the Variance. The variance in the Squared differences from the mean and the "n" in the ArcGIS Setting refers to the population.
So what is really happening? Is ArcGIS replacing each Height value with a StdDev value calculated by neighbouring "n" pixels? That would mean the colours represent the average "spread" of heights and not the actual height values themselves.
Am I on the right track here?