FL Bus Stops

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Researchers at the Center for Urban Transportation Research [1] at the University of South Florida conducted a project in 2010-2011 to assess the feasibility of using public-domain and crowd-sourced data (such as OpenStreetMap) to support multimodal trip planning [2][3]. The team consisted of

  • a geographer who had been actively mapping in OSM, using Potlatch to trace over imagery, work with uploaded GPS traces, and edit and tag from photographs taken while walking through areas mapped by tracing or GPS;
  • a computer scientist who had extensive experience in programming cell phones for location-based services; and
  • two students in computer science.

As part of this project, the team contacted public transportation agencies in the state of Florida that had created data files using the General Transit Feed Specification (GTFS) [4] format to describe their systems. GTFS is the format that agencies use when providing data about their systems for use in Google Transit. The team described the project and OpenStreetMap, and requested permission to upload their GTFS bus-stop data into OpenStreetMap. The following agencies responded and gave permission:

  • Hillsborough Area Regional Transit
  • Pinellas Suncoast Transit Authority
  • Miami-Dade Transit
  • Space Coast Area Transit
  • Sarasota County Area Transit

The project developed an open-source software package (GTFS-OSM Synchronization, or GO_Sync) [5] to read an agency's GTFS file, determine its areal extent, check for bus stops within that extent already in OSM, display stops that might be in conflict between the two sets of stops, and allow the user either to match them or to allow import of the GTFS stops into OSM with FIXME tags to indicate possible conflicts. Reflecting the conditions of the first file we worked with, we considered any stops in OSM within 400 meters of a GTFS stop to be potentially in conflict; experience with subsequent files has shown that smaller distances probably are appropriate in most cities. Other than adding FIXME tags, with an explanation, to stops in OSM that might be in conflict, GO_Sync makes no changes to any data in OSM when it uploads GTFS stops. GTFS stops that might also be in conflict are also tagged with FIXME and an explanation. The software also creates a route relation for each route recorded in the GTFS file, and adds the appropriate relations to each bus stop node that it uploads. It does not create "way" relations to describe the path of the route, because of the complexity required to split ways, follow dual-carriageways, etc. The design of the software proceeded under several assumptions:

  • that few bus stops have already been mapped in OSM for the city served by the agency. This assumption was valid for most cities in the US as of the time the project was conducted, with the main exceptions being the largest metropolitan areas. GO_Sync should not be used in areas where the local OSM mapping community has already mapped a substantial number of the agency's bus stops.
  • that an agency may want to download data that it has uploaded, to identify changes in location or attributes made by the OSM community, to improve the quality of its data;
  • that an agency may want to maintain currency of the data it has uploaded to OSM, as a way of supporting independent developers of software services for its ridership;

Prior to each upload, project staff checked the area to be affected, determined whether any bus stops had been mapped in the area in OSM, and sent a note to the OSM-user-address of the person listed on the most current version of each stop in OSM. The note described the project and the planned imports, asked if there were any questions, asked to provide feedback on the locational accuracy of the import, and offered to remove the upload if it created problems. In most cases, there was no reply. One mapper expressed enthusiasm. Two responded that they were active primarily in other areas and didn't mind. In one area (Space Coast), no bus stops had been previously mapped in OSM. All replies occurred within 3 days of the contact. After a week or so in each case, we uploaded the GTFS stops for four of the five agencies; there were problems with the GTFS file that Sarasota provided, and staff turnover at that agency has to date precluded correcting the problems and proceeding with the upload.

This page is in progress, more information including tagging will be added later.--EdH 16:56, 21 December 2010 (UTC)

See also