🤖 AI Summary
Quantifying uncertainty in quantities of interest (QoIs) for nonlinear models requires experiment designs that directly target predictive uncertainty reduction, rather than conventional parameter-level uncertainty.
Method: We propose a goal-oriented Bayesian optimal experimental design (OED) framework that maximizes the expected information gain (EIG) about the QoI—rather than model parameters—under nonlinear observation and prediction operators. We develop a theoretical foundation for QoI-oriented OED, introduce a nested Monte Carlo estimator combining MCMC-based posterior sampling with kernel density estimation for high-accuracy EIG computation, and employ Bayesian optimization to efficiently identify optimal experimental configurations.
Results: Evaluated on multiple benchmark problems and a convection–diffusion source inversion task for sensor placement, our approach achieves significantly reduced QoI uncertainty and superior experimental efficiency compared to parameter-oriented OED, establishing a new paradigm for prediction-driven scientific experimentation.
📝 Abstract
Optimal experimental design (OED) provides a systematic approach to quantify and maximize the value of experimental data. Under a Bayesian approach, conventional OED maximizes the expected information gain (EIG) on model parameters. However, we are often interested in not the parameters themselves, but predictive quantities of interest (QoIs) that depend on the parameters in a nonlinear manner. We present a computational framework of predictive goal-oriented OED (GO-OED) suitable for nonlinear observation and prediction models, which seeks the experimental design providing the greatest EIG on the QoIs. In particular, we propose a nested Monte Carlo estimator for the QoI EIG, featuring Markov chain Monte Carlo for posterior sampling and kernel density estimation for evaluating the posterior-predictive density and its Kullback-Leibler divergence from the prior-predictive. The GO-OED design is then found by maximizing the EIG over the design space using Bayesian optimization. We demonstrate the effectiveness of the overall nonlinear GO-OED method, and illustrate its differences versus conventional non-GO-OED, through various test problems and an application of sensor placement for source inversion in a convection-diffusion field.