[
    {
        "id": "osp-22808",
        "type": "article-journal",
        "title": "Audit-First VAPO: Risk-Certified Selective Updates under Imperfect Verification",
        "author": [
            {
                "family": "Hu",
                "given": "Miaobo"
            },
            {
                "family": "Hu",
                "given": "Shuhao"
            },
            {
                "family": "Guo",
                "given": "Xiaobo"
            },
            {
                "family": "Wang",
                "given": "Xin"
            },
            {
                "family": "Wang",
                "given": "Bokun"
            },
            {
                "family": "Chen",
                "given": "Rui"
            },
            {
                "family": "Zha",
                "given": "Daren"
            },
            {
                "family": "Xiao",
                "given": "Jun"
            }
        ],
        "URL": "https://omanscience.com/en/articles/audit-first-vapo-risk-certified-selective-updates-under-imperfect-verification",
        "language": "en",
        "issued": {
            "date-parts": [
                [
                    2026
                ]
            ]
        },
        "abstract": "Imperfect verifiers can assign a harmful update direction even when clipping and regularization bound its magnitude. We introduce Audit-First VAPO, which separates discrete directional admission from continuous magnitude control. An observation-only accept-appeal-abstain policy uses a finite secondary-verification budget; its action trace is frozen before clean labels are joined. Simultaneous finite-sample bounds then certify selected harmful risk, coverage, and verifier-call rate over a predeclared policy family. Conditional Hoeffding-Azuma bounds account for the dependence induced by shared budgets, and rollout or verifier changes initiate a new certification stage. After admission, a bounded trust-clip-KL actuator controls magnitude. We evaluate two models on two reasoning benchmarks against static RLVR, matched-random selection, confidence thresholding, noise correction, and verifier augmentation. On Qwen3.5-0.8B and GSM8K at target risk $ρ=0.08$, RC-VAPO achieves 74.1% accuracy, selected harmful risk 0.0697, coverage 0.4125, and relative verifier cost $1.16\\times$. At matched coverage and update magnitude, its selected-risk difference from matched random is -0.0260 with paired 95% interval $[-0.0364,-0.0157]$. Across asymmetric, confidence-dependent, and correlated-verifier noise, the certificate is satisfied on 57 of 60 independent runs. These comparisons isolate informative directional selection from proposal suppression, update shrinkage, and additional verifier computation."
    }
]