aiqbench analysis
This research introduces a closed-form least squares training method for quadratic neural networks, offering a computationally efficient alternative to iterative backpropagation by providing analytical weight expressions and sensitivity bounds. The approach is particularly relevant for system identification tasks where avoiding local minima and reducing computational overhead are critical for deploying advanced models in control systems. By linking optimization lower bounds to nuclear norm minimization, the study advances theoretical understanding of training dynamics in nonlinear architectures.
Regularized Least Squares Training of Quadratic Neural Networks with Applications to System Identification
arXiv:2609.17654v1 Announce Type: new Abstract: This paper proposes a least squares approach for the training of quadratic neural networks with regularization. The proposed methodology yields a lower bound on the solution of the training optimization problem for the case where the regularization coefficient is positive. Moreover, it yields closed-form expressions for the approximate solution and its sensitivity The lower bound is tight and the approximate solution is the optimal solution when the regularization coefficient is zero. Having a closed-form expression for the weights reduces considerably the computational time when compared with iterative numerical methods such as backpropagation that can get stuck in local minima. The proposed approach has three main contributions, namely, (i) it yields an analytical expression for the weights, (ii) an analytical expression for the sensitivity of the weights to errors in the data is also provided, (iii) it establishes a connection between the optimization to compute a lower bound and nuclear norm minimization. The proposed least squares training is successfully applied to a nonlinear system identification example where the proposed lower bound is compared with the optimal value.
Abstract:This paper proposes a least squares approach for the training of quadratic neural networks with regularization. The proposed methodology yields a lower bound on the solution of the training optimization problem for the case where the regularization coefficient is positive. Moreover, it yields closed-form expressions for the approximate solution and its sensitivity The lower bound is tight and the approximate solution is the optimal solution when the regularization coefficient is zero. Having a closed-form expression for the weights reduces considerably the computational time when compared with iterative numerical methods such as backpropagation that can get stuck in local minima. The proposed approach has three main contributions, namely, (i) it yields an analytical expression for the weights, (ii) an analytical expression for the sensitivity of the weights to errors in the data is also provided, (iii) it establishes a connection between the optimization to compute a lower bound and nuclear norm minimization. The proposed least squares training is successfully applied to a nonlinear system identification example where the proposed lower bound is compared with the optimal value.
Machine Learning (cs.LG); Systems and Control (eess.SY)
arXiv:2609.17654 [cs.LG]
(or arXiv:2609.17654v1 [cs.LG] for this version)
https://doi.org/10.48550/arXiv.2609.17654 Focus to learn more arXiv-issued DOI via DataCite
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