I see all the data here on speed, time, altitude, plotted as nice precise points, but I don't see anything on measurement error.
Time - I'm assuming no measurement error (or perhaps a few ms at most)
Speed - what's a reasonable error bar here? What factors would increase that error bar?
Altitude - what's a reasonable error bar here? What factors would increase that error bar?
Location - I'm assuming this is GPS, so with a few feet. Fair?