arXiv:2605.03816stat.MLcs.LG2026-05

用二维矩阵拆解分类器概率质量,区分校准与判别能力。

The Manokhin Probability Matrix: A Diagnostic Framework for Classifier Probability Quality

  • 基于Z统计量和AUC预期排名划分四类诊断模型
  • 实证发现多数模型属'校准差判别弱'或'判别强校准差'
  • 建议先优化判别力再调校准,避免盲目最小化整体误差

Brier得分混淆了概率预测的两个独立属性:可靠性(校准误差)与分辨力(判别能力)。我们提出曼奥金概率矩阵,一种类似BCG的二维诊断框架,将二者分离。通过斯皮格尔哈尔特Z统计量和AUC-ROC预期排名,将分类器置于2×2网格中,并归为四类:鹰(两者皆优)、公牛(判别强但校准差)、懒猫(校准好但判别弱)、鼹鼠(两者皆差)。每类对应不同改进策略。我们在涵盖21个分类器、5种后处理校准器和30个真实二分类任务的大型实证研究中填充该矩阵,使用TabArena-v0.1数据集。分类结果明确:CatBoost、TabICL、EBM、TabPFN、GBC、随机森林为鹰;XGBoost、LightGBM、HGB为公牛;Venn-Abers校准在公牛上使对数损失降低6.5%至12.6%,但在鹰类模型上恶化2.1%;SVM、LR、LDA及经验基线预测为懒猫;MLP、KNN、朴素贝叶斯、ExtraTrees为鼹鼠。理论表明:无序保持的后处理校准无法提升判别力(命题1),故校准可修复,判别力难提升。实践原则是:未分解前勿优化整体Brier得分;应先优化判别力,再事后校准。代码与原始实验数据见https://github.com/valeman/classifier_calibration。

原文摘要 · Abstract (English)

The Brier score conflates two distinct properties of probabilistic predictions: reliability (calibration error) and resolution (discriminatory power). We introduce the Manokhin Probability Matrix, a BCG-style two-dimensional diagnostic framework that separates them. Classifiers are placed on a 2x2 grid by Spiegelhalter Z-statistic and AUC-ROC expected rank, then assigned to one of four archetypes: Eagle (good on both axes), Bull (strong discrimination, poor calibration), Sloth (well-calibrated, weak discriminator), and Mole (poor on both). Each archetype carries a distinct prescription. We populate the matrix from a large-scale empirical study spanning 21 classifiers, 5 post-hoc calibrators, and 30 real-world binary classification tasks from the TabArena-v0.1 suite. The assignment is unambiguous. CatBoost, TabICL, EBM, TabPFN, GBC, and Random Forest are Eagles. XGBoost, LightGBM, and HGB are Bulls; Venn-Abers calibration cuts log-loss by 6.5 to 12.6% on Bulls but degrades Eagles by 2.1%. SVM, LR, LDA, and the empirical base-rate predictor are Sloths. MLP, KNN, Naive Bayes, and ExtraTrees are Moles. A theoretical asymmetry follows: no order-preserving post-hoc calibrator can add discriminatory power (Proposition 1), so calibration is the fixable part and discrimination is the hard part. The practical rule is direct: do not optimise aggregate Brier score without first decomposing it; optimise discrimination first, then fix calibration post-hoc. Code and raw experimental data are available at https://github.com/valeman/classifier_calibration.

概率校准分类评估诊断框架机器学习

Thank you to arXiv for use of its open access interoperability. PaperDance 不是 arXiv 官方产品;中文卡片由大模型生成,请以原文为准。