- Journal
- RAS Techniques and Instruments
- Authors
- A. Mann (sole author)
- Data
- TESS, 20-second cadence, 80 M dwarfs
- Code and data
- doi:10.5281/zenodo.23278174
Onset leakage in ML stellar flare forecasting
I introduce a model-agnostic guard-gap cross-validation test that measures how much of a flare-forecasting classifier's score comes from reading the flare onset inside its input window, rather than predicting it. Applied to an LSTM forecaster on 80 M dwarfs (TESS 20-s cadence, leave-one-star-out), a 10-minute guard cut the robust mean ROC-AUC from 0.997 to 0.870, against a within-star permutation floor of 0.492 ± 0.026. The final ten minutes carry about a quarter of the above-chance signal.