Fix: a bus appears to travel impossibly fast between two stops
Code: fast_travel_between_consecutive_stops (MobilityData validator)
What this means
For some trips, the time between two consecutive stops in stop_times.txt is too
short for the distance between them: the implied speed is faster than a bus could
go. Either a stop time is wrong or a stop is in the wrong place.
Why it matters
Wrong times or locations make trip planners give riders bad arrival predictions
and draw routes that jump around the map. A single fat-fingered time can make a
whole trip look unreliable. The usual causes are a typo in a stop time, a stop
placed at the wrong coordinates, or two stops that are actually the same place.
How to fix it
Check the trips the validator flags:
- A wrong stop time: correct the
arrival_time/departure_timeso the
segment takes a realistic amount of time.
- A misplaced stop: fix the
stop_lat/stop_loninstops.txtso the
distance is right. A stop dropped at 0,0 or at the wrong corner is a common
cause.
- Duplicate stops: if two consecutive stops are the same physical location,
merge them or remove the duplicate.
How long it usually takes
A targeted fix on the flagged trips. The count tells you how widespread it is; a
single bad stop can explain many flagged segments at once.