I can get a measurement of my distance between points (x1,y1,z1 and x2,y2,z2) by analysing position data from a GPS/barometer system, which has a standard deviation of about 2m for x y z positions. I can also analyse data from a system that provides velocity with a standard deviation of about 0.5 m/s for x y z velocities. I integrated the magnitude of the velocity values, obtained position and used this to find distance. Given that I have 2 values for distance, how should I combine them to report the best estimate? I have not repeated the experiment. The object moved while the two devices outputted their measurements.