STD in cell statistic

[ChenMeged]

How standard deviation is calculated for number of rasters in the Cell statistic tool?

The output is a raster where each pixel represent the STD. I want to understand the equation behind it.

[DavidPike · Accepted solution]

There's nothing complex going on, its the STD calculated from coincident raster cell values.

Standard Deviation and Variance (mathsisfun.com)

[DanPatterson · Accepted solution]

You must have missed the reference 

How Cell Statistics works—ArcGIS Pro | Documentation

The basic STD equation uses the population method and not the sample. 

Note that the standard deviation is calculated on the entire population (the N method); it is not estimated based on a sample (the N-1 method).

[DanPatterson]

Answered?  It is still open.  Do you need more information?