Differentiable Likelihoods for Fast Inversion of 'Likelihood-Free' Dynamical Systems
arXiv:2002.09301
Abstract
Likelihood-free (a.k.a. simulation-based) inference problems are inverse problems with expensive, or intractable, forward models. ODE inverse problems are commonly treated as likelihood-free, as their forward map has to be numerically approximated by an ODE solver. This, however, is not a fundamental constraint but just a lack of functionality in classic ODE solvers, which do not return a likelihood but a point estimate. To address this shortcoming, we employ Gaussian ODE filtering (a probabilistic numerical method for ODEs) to construct a local Gaussian approximation to the likelihood. This approximation yields tractable estimators for the gradient and Hessian of the (log-)likelihood. Insertion of these estimators into existing gradient-based optimization and sampling methods engenders new solvers for ODE inverse problems. We demonstrate that these methods outperform standard likelihood-free approaches on three benchmark-systems.
11 pages (+ 5 pages appendix), 6 figures
References in corpus (7)
- The frontier of simulation-based inference
- A Conceptual Introduction to Hamiltonian Monte Carlo
- GPS-ABC: Gaussian Process Surrogate Approximate Bayesian Computation
- Probabilistic Numerical Methods for PDE-constrained Bayesian Inverse Problems
- Probabilistic ODE Solvers with Runge-Kutta Means
- Strong convergence rates of probabilistic integrators for ordinary differential equations
- Implicit Probabilistic Integrators for ODEs