Maps, Models, and Mobility: GPT Goes for a Walk
Opening — Why this matters now Foundation models are no longer confined to text. They’ve begun crawling out of the linguistic sandbox and into the physical world—literally. As cities digitize and mobility data proliferates, a new question surfaces: Can we build a GPT-style foundation model that actually understands movement? A recent tutorial paper from SIGSPATIAL ’25 attempts exactly that, showing how to assemble a trajectory-focused foundation model from scratch using a simplified GPT-2 backbone. It’s refreshingly honest, decidedly hands-on, and quietly important: trajectory models are the next frontier for location‑aware services, logistics, smart cities, and any business that relies on forecasting movement. ...