Article
CommunityJev Benchmarks & Evaluations
Can the Confidence and Decisions of System 1 Models Be Trusted?
Open, deterministic audit benchmark for System 1 decision models, covering calibration under label-preserving perturbations, cross-question interference, and post-hoc attribution faithfulness across five open-weight models and generative baselines.
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- Nov 2026
Highlights
- Evaluates five open-weight models from 0.8B to 27B against logprob and structured JSON/CoT System 2 baselines.
- Reports provider confidence as a closed-form dispersion transform rather than empirical accuracy.
- Bundling questions in one request caused 11.7% to 22.4% binary flips on Tev1-0.8B, versus 0.1% to 0.2% on Tev1-4B.
- Models at 4B or larger reached ECE_w of 0.030 to 0.087 under syntactic shifts, versus 0.144 logprob and 0.378 JSON.
- S1-SHAP with a logit link recovered 89.3% to 100.0% of disjunctive OR gates, versus 57.1% to 82.1% in probability space.
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It evaluates System 1 decision models on calibration under label-preserving perturbations, cross-question interference when multiple questions are bundled in one request, and post-hoc attribution faithfulness, alongside generative System 2 baselines.
Five open-weight models ranging from 0.8B to 27B parameters, compared against generative System 2 baselines using single-token logprob scoring and structured JSON/CoT decoding.
NLI (e-SNLI), adversarial syntactic shortcuts (HANS), synthetic clinical triage (N=900), prompt injection defense (Tensor Trust, N=250), and an 86-case logic-gate trigger suite.
The paper reports it as an exact closed-form dispersion transform: 1 - H(p)/ln K on sub-10B models and a normalized margin on Clef-27B, rather than a measure of empirical accuracy.
The audit found directional cross-question interference, with 11.7% to 22.4% binary flips on Tev1-0.8B compared with 0.1% to 0.2% on Tev1-4B.
On Tensor Trust (N=250), models with 4B parameters or more reached 0.988 to 0.998 AUROC with up to 95.2% recall and 0.0% false alarms at 48 to 60 ms.
The abstract describes an open, deterministic audit benchmark but names no maintainer, license, or repository. It covers five open-weight models from 0.8B to 27B and the listed suites; it reports no results for closed frontier models or production deployments.
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