TS-Arena Technical Report -- A Pre-registered Live Forecasting Platform
Marcel Meyer, Sascha Kaltenpoth, Kevin Zalipski, Henrik Albers, Oliver Müller
TL;DR
TS-Arena tackles the TSFM evaluation crisis by turning the test set into the future, unseen at pre-registration, using live data streams and SCD2 historization to preserve provenance and prevent leakage. The platform provides a leakage-resistant, continuously updated benchmarking framework with dual participation modes (containerized and BYOP) and a moving frontier defined by $t_p$, enabling real-time, domain-spanning evaluation (starting in energy) with rolling, scope-aware leaderboards. Primary performance is tracked by $MASE$, with plans to incorporate probabilistic metrics like CRPS, and to broaden domain coverage while strengthening governance and auditability. This work demonstrates feasibility through an energy-focused prototype and outlines a scalable path toward robust, leakage-resistant forecasting benchmarks across multiple domains.
Abstract
While Time Series Foundation Models (TSFMs) offer transformative capabilities for forecasting, they simultaneously risk triggering a fundamental evaluation crisis. This crisis is driven by information leakage due to overlapping training and test sets across different models, as well as the illegitimate transfer of global patterns to test data. While the ability to learn shared temporal dynamics represents a primary strength of these models, their evaluation on historical archives often permits the exploitation of observed global shocks, which violates the independence required for valid benchmarking. We introduce TS-Arena, a platform that restores the operational integrity of forecasting by treating the genuinely unknown future as the definitive test environment. By implementing a pre-registration mechanism on live data streams, the platform ensures that evaluation targets remain physically non-existent during inference, thereby enforcing a strict global temporal split. This methodology establishes a moving temporal frontier that prevents historical contamination and provides an authentic assessment of model generalization. Initially applied within the energy sector, TS-Arena provides a sustainable infrastructure for comparing foundation models under real-world constraints. A prototype of the platform is available at https://huggingface.co/spaces/DAG-UPB/TS-Arena.
