Determining the Optimal Neural Network Architecture and Parameters: A Comprehensive Review and Practical Manual for Data Scientists
Abstract
The performance of a Neural Network (NN) critically depends on its architecture and parameter configuration. Selecting optimal network depth, width, activation functions, and training hyperparameters is a nontrivial task that substantially influences convergence speed, generalization ability, and computational efficiency. Despite significant progress in optimization and Auto Machine Learning (ML) research, a unified practical framework for determining the optimal NN structure for a given dataset remains elusive. This paper presents a comprehensive review of methods for NN optimization, organized across two hierarchical levels: inner-level parameter optimization (weights, biases, learning rates) and outer-level architecture optimization (depth, width, activation functions, and other hyperparameters). We systematically examine manual design heuristics, search-based techniques (grid, random, Bayesian), evolutionary and reinforcement-based Neural Architecture Search (NAS), differentiable NAS, and meta-learning approaches. Emerging trends such as differentiable hyperparameter optimization, continuous architecture representations, and operator-based frameworks are also discussed. In addition to the theoretical synthesis, the paper provides a practical manual for data scientists, detailing a step-by-step workflow to design, train, and refine NNs efficiently. The review concludes with an analysis of current challenges and outlines future research directions toward mathematically grounded, unified frameworks for network optimization.
Keywords:
Neural network, Architecture optimization, Hyperparameter tuning, Neural architecture search, Auto Machine learningReferences
- [1] Tan, M., & Le, Q. (2019). EfficientNet: rethinking model scaling for convolutional neural networks. Proceedings of the 36th international conference on machine learning (Vol. 97, pp. 6105–6114). PMLR. https://proceedings.mlr.press/v97/tan19a.html?ref=ji
- [2] Rajpurkar, P., Chen, E., Banerjee, O., & Topol, E. J. (2022). AI in health and medicine. Nature medicine, 28(1), 31–38. https://doi.org/10.1038/s41591-021-01614-0
- [3] Shickel, B., Tighe, P. J., Bihorac, A., & Rashidi, P. (2017). Deep EHR: a survey of recent advances in deep learning techniques for electronic health record (EHR) analysis. IEEE journal of biomedical and health informatics, 22(5), 1589–1604. https://doi.org/10.1109/JBHI.2017.2767063
- [4] Li, L., Jamieson, K., DeSalvo, G., Rostamizadeh, A., & Talwalkar, A. (2018). Hyperband: a novel bandit-based approach to hyperparameter optimization. Journal of machine learning research, 18(185), 1–52. http://jmlr.org/papers/v18/16-558.html
- [5] Bergstra, J., & Bengio, Y. (2012). Random search for hyper-parameter optimization. J. mach. learn. res., 13(null), 281–305. https://dl.acm.org/doi/pdf/10.5555/2188385.2188395
- [6] Snoek, J., Larochelle, H., & Adams, R. P. (2012). Practical bayesian optimization of machine learning algorithms. Advances in neural information processing systems (Vol. 25, pp. 1–9). Curran Associates, Inc. https://proceedings.neurips.cc/paper_files/paper/2012/file/05311655a15b75fab86956663e1819cd-Paper.pdf
- [7] Smith, L. N. (2017). Cyclical learning rates for training neural networks. 2017 ieee winter conference on applications of computer vision (WACV) (pp. 464–472). IEEE. https://doi.org/10.1109/WACV.2017.58
- [8] Gao, Z., & Wang, X. (2019). Deep learning. In Hu, L. & Zhang, Z. (Eds.), EEG signal processing and feature extraction (pp. 325–333). Singapore: Springer Singapore. https://doi.org/10.1007/978-981-13-9113-2_16
- [9] Srivastava, N., Hinton, G., Krizhevsky, A., Sutskever, I., & Salakhutdinov, R. (2014). Dropout: a simple way to prevent neural networks from overfitting. J. mach. learn. res., 15(1), 1929–1958. https://dl.acm.org/doi/pdf/10.5555/2627435.2670313
- [10] Martens, J., & Grosse, R. (2015). Optimizing neural networks with kronecker-factored approximate curvature. Proceedings of the 32nd international conference on machine learning (Vol. 37, pp. 2408–2417). Lille, France: PMLR. https://proceedings.mlr.press/v37/martens15.html
- [11] Kingma, D. P. (2014). Adam: A method for stochastic optimization. https://doi.org/10.48550/arXiv.1412.6980
- [12] Glorot, X., & Bengio, Y. (2010). Understanding the difficulty of training deep feedforward neural networks. Proceedings of the thirteenth international conference on artificial intelligence and statistics (Vol. 9, pp. 249–256). Chia Laguna Resort, Sardinia, Italy: PMLR. https://proceedings.mlr.press/v9/glorot10a.html
- [13] Duchi, J., Hazan, E., & Singer, Y. (2011). Adaptive subgradient methods for online learning and stochastic optimization. Journal of machine learning research, 12(7), 1–39. https://www.jmlr.org/papers/volume12/duchi11a/duchi11a.pdf
- [14] Vaswani, A., Shazeer, N., Parmar, N., Uszkoreit, J., Jones, L., Gomez, A. N., … & Polosukhin, I. (2017). Attention is all you need. Advances in neural information processing systems (Vol. 30, pp. 1–11). Curran Associates, Inc. https://proceedings.neurips.cc/paper_files/paper/2017/file/3f5ee243547dee91fbd053c1c4a845aa-Paper.pdf
- [15] Loshchilov, I., & Hutter, F. (2016). Sgdr: stochastic gradient descent with warm restarts. https://doi.org/10.48550/arXiv.1608.03983
- [16] He, K., Zhang, X., Ren, S., & Sun, J. (2015). Delving deep into rectifiers: surpassing human-level performance on imagenet classification. Proceedings of the ieee international conference on computer vision (pp. 1026–1034). IEEE International Conference on Computer Vision. https://openaccess.thecvf.com/content_iccv_2015/papers/He_Delving_Deep_into_ICCV_2015_paper.pdf