Dear TinkerForge, 
We recently bought a GPS Bricklet unit and we would like to have some more details about the data received in the callbacks.   
We successfully used the coordinate callback as explained here: https://www.tinkerforge.com/en/doc/Software/Bricklets/GPS_Bricklet_C.html#c-c-gps-bricklet 
The data contains also the EPE value which we read about here: https://www.nps.gov/gis/gps/WhatisEPE.html 
What we did not understand is which confidence interval is used: 50%, 68%, 95%, 99.7?   
We need this information to calculate the position covariance (standard deviation) following this approach: https://en.wikipedia.org/wiki/Standard_deviation#Rules_for_normally_distributed_data   
Many thanks, 
Guido