This paper explores learning emulators for parameter estimation with uncertainty estimation of high-dimensional dynamical systems. We assume access to a computationally complex simulator that inputs a candidate parameter and outputs a corresponding multichannel time series. Our task is to accurately estimate a range of likely values of the underlying parameters. Standard iterative approaches necessitate running the simulator many times, which is computationally prohibitive. This paper describes a novel framework for learning feature embeddings of observed dynamics jointly with an emulator that can replace high-cost simulators for parameter estimation. Leveraging a contrastive learning approach, our method exploits intrinsic data properties within and across parameter and trajectory domains. On a coupled 396-dimensional multiscale Lorenz 96 system, our method significantly outperforms a typical parameter estimation method based on predefined metrics and a classical numerical simulator, and with only 1.19% of the baseline's computation time. Ablation studies highlight the potential of explicitly designing learned emulators for parameter estimation by leveraging contrastive learning.
翻译:本文探讨以高维动态系统不确定性估算参数的学习模拟器。 我们假设使用一个计算复杂的模拟器, 输入一个候选参数和相应的多通道时间序列。 我们的任务是准确估计基础参数的可能值范围。 标准迭代方法需要多次运行模拟器, 这是一种计算上无法使用的方法。 本文描述了一个与一个模拟器共同学习观测到的动态特征嵌入的新框架, 模拟器可以取代高成本模拟器进行参数估测。 利用反向学习方法, 我们的方法在参数和轨道域内部和之间利用了内在数据属性。 在一个相加的396维多级Lorenz 96系统中, 我们的方法大大超越了基于预先定义的参数和经典数字模拟器的典型参数估算法, 并且只有1. 19 % 的基准计算时间。 对比研究强调通过利用对比学习来明确设计参数估算的学习模拟器的潜力。