← Back to all news
arXiv Machine Learning By Yuvraj Verma

What Does 99% Accuracy Measure? A Reproducible Audit of Shortcut Learning in a Widely Used Fake News Corpus

Read the original on arXiv Machine Learning →

The paper audits the widely used ISOT/Kaggle Fake and Real News corpus and finds that extremely high reported accuracies (≈0.98) are largely due to shortcut signals rather than genuine veracity detection. A simple TF‑IDF linear classifier achieves perfect F1 when using only subject metadata, and even after removing metadata, newswire tags, and duplicate documents, the F1 drops only modestly, indicating that editorial style rather than specific tokens drives performance. Under topic‑disjoint and temporal transfer tests, performance collapses, and models transfer poorly to the independent LIAR benchmark, showing that within‑corpus scores reflect source and topic separability, not truth verification. whyItMatters:"The study demonstrates that current high accuracy metrics on this fake‑news dataset are misleading, highlighting the need for more robust evaluation protocols that guard against shortcut learning."

Machine-generated by The Flow from the publisher's headline and feed description — not written or checked by a human. The full article lives at arXiv Machine Learning.

Related stories

arXiv Machine Learning
Oct 12

Forecasting Corpus-Sampling Disagreement in Masked Text Reconstruction

The paper investigates how much a masked‑text reconstruction predictor’s outputs would differ if a second corpus were collected from the same population. Using a smoothed predictor based on token‑pair counts, the authors derive a first‑order formula for expected disagreement between predictors trained on two independent corpora, accounting for document length, random context counts, and token‑offset correlations. Experiments on TinyStories, WikiText‑103, and CNN/DailyMail show that increasing corpus size from 512 to 2,048 chunks of 64 tokens reduces disagreement only modestly (5–40 %), and that forecast accuracy improves with larger reference corpora and a source‑split jackknife correction. whyItMatters:"The study provides a practical method to estimate how much predictor outputs would change with additional data, informing decisions about data collection and model robustness in masked‑text reconstruction tasks."

By Hare Krishna
llmsdiffusion
More like this →
arXiv AI
Oct 5

Sentence-Level Context Sensitivity as a Training-Free Detector of Unsupported Content, Evaluated Against Trained Verifiers

The paper proposes a training‑free detector that uses sentence‑level context sensitivity to identify unsupported content in retrieval‑augmented generation (RAG) answers. By re‑scoring each sentence with full context, no context, and each chunk removed, the method flags the chunk whose removal most reduces a sentence’s likelihood as the likely source. Evaluated on RAGTruth, TofuEval, and RAGBench, the detector outperforms answer‑level faithfulness scores, achieving AUCs up to 0.745 and matching per‑chunk fact‑checkers while using only a fraction of the compute required by large‑language‑model judges.

By Mohamed Aly Bouke
llmsragnlpbenchmarks
More like this →