arXiv Machine Learning By Johann Emmanuel Li

Calibrated Answers About Randomized Trials From a 4-Billion-Parameter Open Model: A Registered Test and a License-Clean Release

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Fiorillo v0.5 is an open 4‑billion‑parameter model that reads a randomized trial article (cut to 6,144 tokens) and predicts whether an intervention significantly increased, decreased, or had no significant effect on an outcome. Fine‑tuned on 1,431 license‑clean training articles, it achieved an expected calibration error of 0.0168, log loss 0.8603 lower than the prior, and macro‑F1 of 0.9248 on a public test split of 1,218 prompts. The model’s release, licensed under Apache 2.0, met all four pre‑registered criteria on the Open Science Framework and was validated against the evaluated predictions.

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