# Data provenance

DataMind builds, reconstructs, and reviews transit data. The published feeds passed the MobilityData GTFS Validator 7.1.0 with zero errors. Their service period, geographic coverage, counts, warnings and checksum appear on each feed card and in the public manifest.

| GTFS component | Origin and source | Transformation |
|---|---|---|
| agency.txt | DataMind operator and agency research; names may include OSM-relation and published transit references | Normalize agency IDs and group services by operator |
| stops.txt | Directly traced OSM records and DataMind review, manual research and backfill | Export source-linked node IDs, names and coordinates; some locations are reconstructed |
| routes.txt | DataMind route inventory, sequence work and reviewed research; some route relations are sourced from OSM | Build route names, operators, directions and GTFS route records |
| trips.txt | DataMind schedule profiles and service patterns | Build trip IDs and links to routes, services and shapes |
| stop_times.txt | DataMind stop sequences and runtime estimates | Generate ordered stop calls, times and distances |
| calendar.txt | DataMind service patterns and feed periods | Export weekday service and effective dates |
| calendar_dates.txt | DataMind researched service exceptions | Export added or removed service dates |
| shapes.txt | DataMind route geometry; 25 exact shape matches trace to persisted Valhalla-family geometry over OSM road tiles | Export ordered GTFS shape points and distances |

In the 17 April Quito/Pichincha and Guayaquil snapshot, 1,883 of 2,707 stop coordinates match original Overpass records. Twenty-five shapes exactly match persisted Valhalla-family candidate geometries. The pipeline compiles original transit work with geographic source data and route geometry. See [the dataset license](DATA-LICENSE.md) and [version history](GTFS-VERSION-HISTORY.md).