Nonlinear dimension reduction for surrogate modeling using gradient information
arXiv:2102.10351 · doi:10.1093/imaiai/iaac006
Abstract
We introduce a method for the nonlinear dimension reduction of a high-dimensional function , . Our objective is to identify a nonlinear feature map , with a prescribed intermediate dimension , so that can be well approximated by for some profile function . We propose to build the feature map by aligning the Jacobian with the gradient , and we theoretically analyze the properties of the resulting . Once is built, we construct by solving a gradient-enhanced least squares problem. Our practical algorithm makes use of a sample and builds both and on adaptive downward-closed polynomial spaces, using cross validation to avoid overfitting. We numerically evaluate the performance of our algorithm across different benchmarks, and explore the impact of the intermediate dimension . We show that building a nonlinear feature map can permit more accurate approximation of than a linear , for the same input data set.