The skip factor for calculating statistics on a file geodatabase raster is based on the pyramid levels available. The skip factor uses all the pixels in a pyramid level to calculate statistics. Consequently, pyramids have to be present for the file geodatabase raster in order for the skip factor to take effect, otherwise statistics will be calculated based on all pixels in the raster.
The skip factor relates to the pyramid level as follows:
A skip factor of 1 is equal to pyramid level 0.
A skip factor of 2 or 3 is equal to pyramid level 1.
A skip factor of 4 through 7 is equal to pyramid level 2.
For example: if a skip factor of 50 for columns and 50 for rows is used, then pyramid level 5 will be used to calculate the statistics.
If the skip factor converts to a pyramid level that is greater than the raster dataset's maximum pyramid level, then the maximum pyramid level is used to calculate statistics.
This only relates to the calculate statistics skip factor in a file geodatabase or SDE.