论文标题
黑盒贝叶斯推断基于经济代理的模型
Black-box Bayesian inference for economic agent-based models
论文作者
论文摘要
仿真模型,特别是基于代理的模型,在经济学中广受欢迎。他们提供的可观的灵活性以及它们重现各种经验观察到的复杂系统行为的能力,使它们具有广泛的吸引力,廉价计算能力的可用性增加使它们的使用可行。然而,在这种模型执行参数估计的困难中,在现实世界建模和决策方案中广泛采用。通常,仿真模型缺乏可拖动的似然函数,这阻止了标准统计推理技术的直接应用。最近的一些著作试图通过应用无似然推理技术来解决此问题,其中参数估计是通过在观察到的数据和仿真输出之间进行某种形式的比较来确定的。但是,这些方法是基于限制性假设的(a),/或(b)通常需要数十万个模拟。这些品质使它们不适合经济学的大规模模拟,并且在这种情况下可能对这些推论方法的有效性产生怀疑。在本文中,我们研究了两类黑盒近似贝叶斯推理方法的功效,这些方法最近在概率机器学习社区中引起了很大的关注:神经后验估计和神经密度比估计。我们提出了基准测试实验,其中我们证明了基于神经网络的黑框方法为经济仿真模型提供了艺术参数推断的状态,并且与通用的多元时间序列数据至关重要。此外,我们建议适当的评估标准,用于对经济仿真模型的近似贝叶斯推理程序的未来基准测试。
Simulation models, in particular agent-based models, are gaining popularity in economics. The considerable flexibility they offer, as well as their capacity to reproduce a variety of empirically observed behaviours of complex systems, give them broad appeal, and the increasing availability of cheap computing power has made their use feasible. Yet a widespread adoption in real-world modelling and decision-making scenarios has been hindered by the difficulty of performing parameter estimation for such models. In general, simulation models lack a tractable likelihood function, which precludes a straightforward application of standard statistical inference techniques. Several recent works have sought to address this problem through the application of likelihood-free inference techniques, in which parameter estimates are determined by performing some form of comparison between the observed data and simulation output. However, these approaches are (a) founded on restrictive assumptions, and/or (b) typically require many hundreds of thousands of simulations. These qualities make them unsuitable for large-scale simulations in economics and can cast doubt on the validity of these inference methods in such scenarios. In this paper, we investigate the efficacy of two classes of black-box approximate Bayesian inference methods that have recently drawn significant attention within the probabilistic machine learning community: neural posterior estimation and neural density ratio estimation. We present benchmarking experiments in which we demonstrate that neural network based black-box methods provide state of the art parameter inference for economic simulation models, and crucially are compatible with generic multivariate time-series data. In addition, we suggest appropriate assessment criteria for future benchmarking of approximate Bayesian inference procedures for economic simulation models.