Algorithmic Analysis of GTFS-RT vehicle position accuracy

Joshua Wong

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arXiv · 2506.06479

Algorithmic Analysis of GTFS-RT vehicle position accuracy

Joshua Wong

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Abstract

This paper presents three novel algorithms for calculating geodesic intersections on an ellipsoid. These algorithms are applied in a case study analyzing real-time transit data in California to assess vehicle position drift. The analysis reveals that while certain data anomalies can be corrected, large-scale discrepancies persist. The paper concludes by proposing a set of practical solutions that can be implemented by either data producers or consumers to significantly improve positional accuracy.

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Joshua Wong. 2025-06-06. Algorithmic Analysis of GTFS-RT vehicle position accuracy. https://arxiv.org/abs/2506.06479

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