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arXiv 1902.04827stat.CO
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使用合成似然的贝叶斯推断:渐近性和调整

Bayesian inference using synthetic likelihood: asymptotics and adjustments

David T. Frazier, David J. Nott, Christopher Drovandi, Robert Kohn

摘要:

在涉及复杂模型的应用中,实现贝叶斯推断通常在计算上具有挑战性,有时计算可能性本身也很困难。当可能性难以处理时,合成可能性是一种进行推理的方法,但从模型进行模拟是直接的。该方法通过将向量汇总统计量视为多变量正态分布来构建近似似然,其中未知均值和协方差阵通过模拟对任何给定参数值进行估计。本文有三个贡献。第一个表明,如果汇总统计量满足中心极限定理,则合成似然后验是渐近正态的,并产生具有正确频率覆盖水平的可信集。这一结果与近似贝叶斯计算结果相似。第二个贡献比较贝叶斯合成似然和近似贝叶斯计算的计算效率使用的接受概率拒绝和重要性抽样算法与"好"的建议分布。我们表明,贝叶斯合成似然比近似贝叶斯计算更有效的计算,并表现出类似的回归调整近似贝叶斯计算。基于渐近结果,第三个贡献,提出使用调整的推断方法时,可能误指定的形式,假定为合成似然的协方差阵,如对角或因子模型,以加快计算。该方法说明了一些模拟和真实的例子。

英文摘要:

Implementing Bayesian inference is often computationally challenging in applications involving complex models, and sometimes calculating the likelihood itself is difficult. Synthetic likelihood is one approach for carrying out inference when the likelihood is intractable, but it is straightforward to simulate from the model. The method constructs an approximate likelihood by taking a vector summary statistic as being multivariate normal, with the unknown mean and covariance matrix estimated by simulation for any given parameter value. Our article makes three contributions. The first shows that if the summary statistic satisfies a central limit theorem, then the synthetic likelihood posterior is asymptotically normal and yields credible sets with the correct level of frequentist coverage. This result is similar to that obtained by approximate Bayesian computation. The second contribution compares the computational efficiency of Bayesian synthetic likelihood and approximate Bayesian computation using the acceptance probability for rejection and importance sampling algorithms with a "good" proposal distribution. We show that Bayesian synthetic likelihood is computationally more efficient than approximate Bayesian computation, and behaves similarly to regression-adjusted approximate Bayesian computation. Based on the asymptotic results, the third contribution proposes using adjusted inference methods when a possibly misspecified form is assumed for the covariance matrix of the synthetic likelihood, such as diagonal or a factor model, to speed up the computation. The methodology is illustrated with some simulated and real examples.

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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