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arXiv 2203.11276stat.MLcs.LG
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近似贝叶斯计算中的模型比较

Model Comparison in Approximate Bayesian Computation

Bernstein Center for Computational Neuroscience(伯恩斯坦计算神经科学中心)

Jan Boelts

摘要:

自然科学中的一个常见问题是根据观测数据比较竞争模型。贝叶斯模型比较基于每个模型为数据提供的证据,为这种比较提供了一个统计上合理的框架。然而,这种框架依赖于似然函数的计算,这对于实践中使用的大多数模型来说是难以处理的。近似贝叶斯计算(ABC)领域中的先前方法规避了对似然的评估并且基于拒绝抽样来估计模型证据,但是它们通常是计算密集的。在这里,我提出了一种新的有效的方法来执行贝叶斯模型比较ABC。基于后验密度估计的最新进展,该方法以参数形式逼近后验模型。特别是,我训练一个混合密度网络,将观察数据的特征映射到模型的后验概率。性能评估与两个例子。在一个易于处理的模型比较问题上,可以准确地预测潜在的精确后验概率。在计算神经科学的一个用例场景中--两个离子通道模型之间的比较--底层的地面实况模型被可靠地分配了高后验概率。总的来说,该方法提供了一种新的有效的方式来执行贝叶斯模型比较复杂的生物物理模型的模型架构无关。

英文摘要:

A common problem in natural sciences is the comparison of competing models in the light of observed data. Bayesian model comparison provides a statistically sound framework for this comparison based on the evidence each model provides for the data. However, this framework relies on the calculation of likelihood functions which are intractable for most models used in practice. Previous approaches in the field of Approximate Bayesian Computation (ABC) circumvent the evaluation of the likelihood and estimate the model evidence based on rejection sampling, but they are typically computationally intense. Here, I propose a new efficient method to perform Bayesian model comparison in ABC. Based on recent advances in posterior density estimation, the method approximates the posterior over models in parametric form. In particular, I train a mixture-density network to map features of the observed data to the posterior probability of the models. The performance is assessed with two examples. On a tractable model comparison problem, the underlying exact posterior probabilities are predicted accurately. In a use-case scenario from computational neuroscience -- the comparison between two ion channel models -- the underlying ground-truth model is reliably assigned a high posterior probability. Overall, the method provides a new efficient way to perform Bayesian model comparison on complex biophysical models independent of the model architecture.

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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