arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2002.10399stat.MEcs.LGstat.ML
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无似然推理中的置信集与假设检验

Confidence Sets and Hypothesis Testing in a Likelihood-Free Inference Setting

Carnegie Mellon University(卡内基梅隆大学);Federal University of São Carlos(圣卡洛斯联邦大学)

Niccolò Dalmasso, Rafael Izbicki, Ann B. Lee

摘要:

参数估计、统计检验和置信度集是经典统计学的基石,使科学家能够对产生观测数据的基本过程进行推断。一个关键问题是,在所谓的无似然推理(LFI)设置中,是否仍然可以构建具有适当覆盖率和高功率的假设检验和置信集;也就是说,可能性不明确,但可以根据随机模型向前模拟可观察数据的设置。在本文中,我们提出了$\texttt{ACORE}$(通过比值比估计的近似计算),一个频率主义的方法,LFI,首先制定了经典的似然比检验(LRT)作为一个参数化的分类问题,然后使用测试和置信集的等价性,建立置信区域的参数感兴趣。我们还提出了一个良好的拟合过程,用于检查是否构造的测试和置信区域是有效的。$\texttt{ACORE}$基于以下关键观察结果:LRT统计量、测试的拒绝概率和置信集的覆盖率是条件分布函数,其通常作为感兴趣参数的函数平滑变化。因此,不是仅仅依赖于在固定参数设置下模拟的样本(如标准蒙特卡罗解决方案中的惯例),而是可以利用机器学习工具和在参数附近模拟的数据来改进对感兴趣的量的估计。我们证明了$\texttt{ACORE}$的有效性与理论和实证结果。我们的实现可以在Github上找到。

英文摘要:

Parameter estimation, statistical tests and confidence sets are the cornerstones of classical statistics that allow scientists to make inferences about the underlying process that generated the observed data. A key question is whether one can still construct hypothesis tests and confidence sets with proper coverage and high power in a so-called likelihood-free inference (LFI) setting; that is, a setting where the likelihood is not explicitly known but one can forward-simulate observable data according to a stochastic model. In this paper, we present $\texttt{ACORE}$ (Approximate Computation via Odds Ratio Estimation), a frequentist approach to LFI that first formulates the classical likelihood ratio test (LRT) as a parametrized classification problem, and then uses the equivalence of tests and confidence sets to build confidence regions for parameters of interest. We also present a goodness-of-fit procedure for checking whether the constructed tests and confidence regions are valid. $\texttt{ACORE}$ is based on the key observation that the LRT statistic, the rejection probability of the test, and the coverage of the confidence set are conditional distribution functions which often vary smoothly as a function of the parameters of interest. Hence, instead of relying solely on samples simulated at fixed parameter settings (as is the convention in standard Monte Carlo solutions), one can leverage machine learning tools and data simulated in the neighborhood of a parameter to improve estimates of quantities of interest. We demonstrate the efficacy of $\texttt{ACORE}$ with both theoretical and empirical results. Our implementation is available on Github.

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。

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