arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2001.05360stat.ME
收藏

数据集移位下的广义贝叶斯量化学习

Generalized Bayes Quantification Learning under Dataset Shift

Jacob Fiksel, Abhirup Datta, Agbessi Amouzou, Scott Zeger

摘要:

量化学习是使用来自在不同人群上训练的分类器的预测来估计测试人群的患病率的任务。量化方法假设分类器的灵敏度和特异性是完美的,或者可以从训练群体转移到测试群体。这些假设是不适当的数据集移位的存在下,当在训练人口的错误分类率是不代表的测试人口。数据集偏移下的量化仅针对单类(分类)预测进行了讨论,并假设完全了解测试人群的一小部分上的真实标签。我们提出了广义贝叶斯量化学习(GBQL),它使用概率分类器的整个组成预测,并允许有限的标记测试数据的真实类标签的不确定性。而不是提出一个完整的模型,我们使用一个无模型的贝叶斯估计方程的方法,成分数据的基础上,只有一个第一时刻的假设。这个想法将是有用的贝叶斯组成数据分析一般,因为它是强大的组成数据的不同生成机制,包括分类输出作为一个特殊情况。我们展示了我们的方法如何产生现有的量化方法作为特殊情况。扩展到集成GBQL,使用多个分类器的预测产生的推理鲁棒性包括一个穷人的分类器进行了讨论。我们概述了一个快速,高效的吉布斯采样器使用四舍五入和粗化近似的损失函数。我们还建立了GBQL区间估计的后验相合性、渐近正态性和有效覆盖率,以及有限样本后验集中率。通过模拟和分析具有明显数据集偏移的真实数据,证明了GBQL的经验性能。

英文摘要:

Quantification learning is the task of prevalence estimation for a test population using predictions from a classifier trained on a different population. Quantification methods assume that the sensitivities and specificities of the classifier are either perfect or transportable from the training to the test population. These assumptions are inappropriate in the presence of dataset shift, when the misclassification rates in the training population are not representative of those for the test population. Quantification under dataset shift has been addressed only for single-class (categorical) predictions and assuming perfect knowledge of the true labels on a small subset of the test population. We propose generalized Bayes quantification learning (GBQL) that uses the entire compositional predictions from probabilistic classifiers and allows for uncertainty in true class labels for the limited labeled test data. Instead of positing a full model, we use a model-free Bayesian estimating equation approach to compositional data based only on a first-moment assumption. The idea will be useful in Bayesian compositional data analysis in general as it is robust to different generating mechanisms for compositional data and includes categorical outputs as a special case. We show how our method yields existing quantification approaches as special cases. Extension to an ensemble GBQL that uses predictions from multiple classifiers yielding inference robust to inclusion of a poor classifier is discussed. We outline a fast and efficient Gibbs sampler using a rounding and coarsening approximation to the loss functions. We also establish posterior consistency, asymptotic normality and valid coverage of interval estimates from GBQL, as well as finite sample posterior concentration rate. Empirical performance of GBQL is demonstrated through simulations and analysis of real data with evident dataset shift.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑