A Theoretical Analysis of Joint Weight–Bias Hessian-Based Initialization Strategies in Deep Learning: Impact on Model Convergence, Curvature, and Accuracy

Authors

  • Pratik Ahire Department of Computer Applications, GH Raisoni College of Engineering and Management, Jalgaon, India
  • Prachi Mawale Department of Computer Applications, GH Raisoni College of Engineering and Management, Jalgaon, India

Keywords:

neural network initialization, Hessian, bias initialization, curvature, variance preservation, second-order optimization, loss landscape, joint parameterization.

Abstract

Conventional neural-network initialization is largely motivated by controlling activation and gradient moments across layers. Xavier/Glorot and He/Kaiming provide effective variance-based rules, but variance preservation alone does not specify how initialization relates to local optimization geometry. Curvature-aware analyses provide a complementary second-order view, while related work has examined scaling, bias behavior, initialization geometry, and mathematically constrained initialization. This paper develops a theoretical Joint Weight–Bias Hessian Initialization Framework in which the weights and biases of a layer are represented by one parameter vector and analyzed through the complete block Hessian. A variance-allocation coordinate r controls how a fixed target pre-activation variance is divided between weights and bias, and a normalized curvature–variance criterion provides a common objective for studying that allocation. The scalar linear-quadratic model is solved exactly, including the joint Hessian, its spectrum, and the variance-constrained family. An important boundary result is established: under standardized scalar assumptions, J(r)=0 for every feasible r, so the scalar model cannot identify a unique allocation. This is a limitation of the simplified model rather than evidence against the framework. The paper therefore presents a mathematically explicit, testable framework and a controlled future protocol for nonlinear MLP and CNN validation, without claiming empirical accuracy or convergence improvements.

References

X. Glorot and Y. Bengio, “Understanding the difficulty of training deep feedforward neural networks,” in Proc. 13th Int. Conf. Artificial Intelligence and Statistics (AISTATS), vol. 9, pp. 249–256, 2010.

K. He, X. Zhang, S. Ren, and J. Sun, “Delving deep into rectifiers: Surpassing human-level performance on ImageNet classification,” in Proc. IEEE Int. Conf. Computer Vision (ICCV), pp. 1026–1034, 2015, doi: 10.1109/ICCV.2015.123.

M. Skorski, A. Temperoni, and M. Theobald, “Revisiting weight initialization of deep neural networks,” in Proc. 13th Asian Conf. Machine Learning (ACML), PMLR 157, pp. 1192–1207, 2021.

A. Orvieto, J. Kohler, D. Pavllo, T. Hofmann, and A. Lucchi, “Vanishing curvature in randomly initialized deep ReLU networks,” in Proc. 25th Int. Conf. Artificial Intelligence and Statistics (AISTATS), PMLR 151, pp. 7942–7975, 2022.

A. M. Vysogorets, A. Dawid, and J. Kempe, “Deconstructing the Goldilocks zone of neural network initialization,” in Proc. 41st Int. Conf. Machine Learning (ICML), PMLR 235, pp. 49717–49732, 2024.

A. Defazio and L. Bottou, “A scaling calculus for the design and initialization of ReLU networks,” Neural Computing and Applications, vol. 34, pp. 14807–14821, 2022, doi: 10.1007/s00521-022-07308-z.

H. Sahs, M. Pyle, S. Damaraju, C. Caro, T. Tavaslioglu, Y. Lu, F. Anselmi, and

P. Patel, “Shallow univariate ReLU networks as splines: Initialization, loss surface, Hessian, and gradient flow dynamics,” Frontiers in Artificial Intelligence, vol. 5, Art. no. 889981, 2022, doi: 10.3389/frai.2022.889981.

I. de Pater and M. Mitici, “A mathematical framework for improved weight initialization of neural networks using Lagrange multipliers,” Neural Networks,

vol. 166, pp. 579–594, 2023, doi: 10.1016/j.neunet.2023.07.035.

H. Lee, Y. Kim, S. Y. Yang, and H. Choi, “Improved weight initialization for deep and narrow feedforward neural network,” Neural Networks, vol. 176, Art. no. 106362, 2024, doi: 10.1016/j.neunet.2024.106362.

S. Fort and A. Scherlis, “The Goldilocks zone: Towards better understanding of neural network loss landscapes,” in Proc. AAAI Conf. Artificial Intelligence, vol. 33, no. 1, pp. 3574–3581, 2019, doi: 10.1609/aaai.v33i01.33013574.

S. Azulay, E. Moroshko, M. S. Nacson, B. E. Woodworth, N. Srebro, N. Globerson, and D. Soudry, “On the implicit bias of initialization shape: Beyond infinitesimal mirror descent,” in Proc. 38th Int. Conf. Machine Learning (ICML), PMLR 139, pp. 468–477, 2021.

G. Bingham and R. Miikkulainen, “AutoInit: Analytic signal-preserving weight initialization for neural networks,” in Proc. AAAI Conf. Artificial Intelligence, vol. 37, no. 6, pp. 6823–6833, 2023, doi: 10.1609/aaai.v37i6.25836.

Published

2026-09-29