TraXion: Rethinking Pre-training Frameworks for Mobility and Beyond
On the map: LLM reasoning → Spatial and embodied reasoning
Abstract (arXiv)
Human mobility differs from text and from generic time series in three structural ways: visits are tuple-valued events whose meaning depends on the joint distribution over location, time, and activity; users carry persistent signatures across trajectories; and visits are not independent across users, since co-location at shared places is a primary signal. Existing pre-training recipes for mobility import objectives from language modeling, treating trajectories as sentences and visits as tokens, an analogy that fails against each of the three properties above. These properties define a broader class, multi-entity spatiotemporal event streams (MESES), spanning enterprise authentication logs, electronic health records, and other event-stream domains where entities share infrastructure, schedules, or contexts. We make the properties precise as three axioms that any pre-training framework for MESES should satisfy, and introduce TraXion, whose objectives and architecture are jointly designed to meet them. A single TraXion checkpoint per dataset beats task-specific baselines on every task across six public mobility datasets covering anomaly detection, next-POI recommendation, next-visit prediction, and social-link prediction. The same recipe, applied unchanged to enterprise authentication logs and ICU mortality prediction, matches or exceeds prior work on both, showing that event streams from domains as different as mobility, security, and healthcare can be modeled under a single framework.
Key facts. No citing papers in the map yet (data through 7 Oct 2026). Placed in Spatial and embodied reasoning, one of 17 directions in LLM reasoning. Builds on 53 of its 77 references that are in the map. First posted on arXiv 7 May 2026.
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References · 53
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- 2026MobiDiff: Semantic-Aware Multi-Channel Discrete Diffusion for Human Mobility Data Generation
- 2025MoveGPT: Scaling Mobility Foundation Models with Spatially-Aware Mixture of Experts
- 2025SeMob: Semantic Synthesis for Dynamic Urban Mobility Prediction
- 2025RHYTHM: Reasoning with Hierarchical Temporal Tokenization for Human Mobility
- 2024A Universal Model for Human Mobility Prediction
- 2026ARMove: Learning to Predict Human Mobility through Agentic Reasoning
- 2024LIMP: Large Language Model Enhanced Intent-aware Mobility Prediction
- 2025MoE-TransMov: A Transformer-based Model for Next POI Prediction in Familiar & Unfamiliar Movements