Statgraphics Standard Error Calculation

Hi guys,
i am working on a DOE Screening, and am trying to figure out how the program calculates the standard error. It does not apply the normal statistical formula of the standard error.
Attached there is a picture of the data that the programs gives. in the first group i have excluded a bunch of interactions, and in the second i just put all of them in again. Does anyone have anyide how it works?? im stuck badly in this :shakehead