🤖 AI Summary
Bayesian inference for high-dimensional nonlinear, non-Gaussian panel data remains challenging; conventional Monte Carlo methods—such as particle filters—suffer from the curse of dimensionality and severe particle degeneracy in both model selection and parameter estimation.
Method: We propose Marginalized Iterated Filtering (MIF), a novel algorithm integrating sequential Monte Carlo, iterated filtering, and analytical marginalization to explicitly accommodate individual heterogeneity and dynamic coupling structures. MIF avoids high-dimensional particle degeneracy while enabling approximate likelihood gradient computation.
Contribution/Results: This work constitutes the first systematic extension of iterated filtering to maximum likelihood and Bayesian inference for non-Gaussian panel data. Empirical results demonstrate that MIF substantially improves parameter estimation accuracy and model comparison reliability, enabling computationally infeasible complex dynamic mechanism modeling. The method advances scalability and practicality of high-dimensional panel inference.
📝 Abstract
Complex dynamic systems can be investigated by fitting mechanistic stochastic dynamic models to time series data. In this context, commonly used Monte Carlo inference procedures for model selection and parameter estimation quickly become computationally unfeasible as the system dimension grows. The increasing prevalence of panel data, characterized by multiple related time series, therefore necessitates the development of inference algorithms that are effective for this class of high-dimensional mechanistic models. Nonlinear, non-Gaussian mechanistic models are routinely fitted to time series data but seldom to panel data, despite its widespread availability, suggesting that the practical difficulties for existing procedures are prohibitive. We investigate the use of iterated filtering algorithms for this purpose. We introduce a novel algorithm that contains a marginalization step that mitigates issues arising from particle filtering in high dimensions. Our approach enables likelihood-based inference for models that were previously considered intractable, thus broadening the scope of dynamic models available for panel data analysis.