论文标题
基于模拟推断的对比性神经比估计
Contrastive Neural Ratio Estimation for Simulation-based Inference
论文作者
论文摘要
可能性与证据比率估计通常被施加为二进制(NRE-A)或多类(NRE-B)分类任务。与二进制分类框架相反,多类版本的当前表述具有内在且未知的偏差术语,这使得其他内容丰富的诊断不可靠。我们提出了一个多类框架,没有最佳的NRE-B固有的偏差,使我们无法运行从业人员依赖的诊断。它还在一个角案件中恢复了NRE-A,在限制案例中恢复了NRE-B。为了进行公平的比较,我们在熟悉和新颖的培训方案中基准了所有算法的行为:当共同绘制的数据是无限的,当数据固定但事先绘制时无限的,并且在普通位置的固定数据和参数设置中。我们的调查表明,性能最高的模型远离竞争对手(NRE-A,NRE-B)在高参数空间中。我们为与以前的模型不同的超参数提出建议。我们建议相互信息作为基于模拟的推理方法的性能指标的两个界限,而无需后验样品,并提供实验结果。此版本纠正了$γ$中的次要实现错误,从而改善了结果。
Likelihood-to-evidence ratio estimation is usually cast as either a binary (NRE-A) or a multiclass (NRE-B) classification task. In contrast to the binary classification framework, the current formulation of the multiclass version has an intrinsic and unknown bias term, making otherwise informative diagnostics unreliable. We propose a multiclass framework free from the bias inherent to NRE-B at optimum, leaving us in the position to run diagnostics that practitioners depend on. It also recovers NRE-A in one corner case and NRE-B in the limiting case. For fair comparison, we benchmark the behavior of all algorithms in both familiar and novel training regimes: when jointly drawn data is unlimited, when data is fixed but prior draws are unlimited, and in the commonplace fixed data and parameters setting. Our investigations reveal that the highest performing models are distant from the competitors (NRE-A, NRE-B) in hyperparameter space. We make a recommendation for hyperparameters distinct from the previous models. We suggest two bounds on the mutual information as performance metrics for simulation-based inference methods, without the need for posterior samples, and provide experimental results. This version corrects a minor implementation error in $γ$, improving results.