arXiv Statistics ML

Optimal Centered Active Excitation in Linear System Identification

The paper introduces an active learning algorithm for linear system identification that uses optimal centered noise excitation. It employs ordinary least squares and semidefinite programming to achieve minimal sample complexity while enabling efficient computation of the system matrix estimate. The authors provide both lower and upper bounds on sample complexity that match up to universal factors and explicitly depend on system parameters such as state dimension.

Hugging Face Trending Papers
Aug 2

Active Regression for Single-Index Models with Unknown Link Functions

This paper studies active regression for single-index models under general $\ell_p$-loss with an unknown $1$-Lipschitz link function $f$, formulated as $\min_{f,x} \|f(Ax)-b\|_p^p$ with full access to $A$ but coordinate-query access to $b$. Prior work established upper bounds for known link functions for all $p\geq 1$ and for unknown link functions only in the $p=2$ case, together with lower bounds for $p\leq 2$.

arXiv Machine Learning
Aug 17

Active Regression via Linear-Sample Sparsification

arXiv:1711. 10051v4 Announce Type: replace Abstract: We present an approach that improves the sample complexity for a variety of curve fitting problems, including active learning for linear regression, polynomial regression, and continuous sparse Fourier transforms.

By Xue Chen, Eric Price
arXiv Machine Learning
Sep 18

Demystifying Linear Operator Learning for Control Systems

The paper introduces a structured method for learning linear operators in control systems using data. It leverages the framework of (semi)groups for evolution equations to establish structural assumptions and applies inverse‑problems theory to analyze learning algorithms, revealing error decompositions, convergence guarantees, and optimal regularization. Focusing on bounded operators on Hilbert spaces, the authors derive a convergent estimator for time‑varying systems, illustrating the practical power of their approach.

By Max Beier, Nicolas Hoischen, Sandra Hirche, Petar Bevanda
arXiv Machine Learning
Aug 14

Fast Length-Squared Sampling for Positive-Semidefinite Matrices

arXiv:2608. 12503v1 Announce Type: cross Abstract: We describe a simple rejection-sampling-based algorithm to perform length-squared sampling on an $n \times n$ positive-semidefinite (psd) matrix: that is, to sample a column with probability proportional to its squared $\ell_2$-norm.

By Rajarshi Bhattacharjee, Ethan N. Epperly, Cameron Musco, Aaron Tian