The Double Descent Behavior in Two Layer Neural Network for Binary Classification
Pub. online: 1 April 2025
Type: Miscellaneous
Open Access
Received
1 October 2024
1 October 2024
Accepted
6 March 2025
6 March 2025
Published
1 April 2025
1 April 2025
Abstract
Recent studies observed a surprising concept on model test error called the double descent phenomenon where the increasing model complexity decreases the test error first and then the error increases and decreases again. To observe this, we work on a two-layer neural network model with a ReLU activation function designed for binary classification under supervised learning. Our aim is to observe and investigate the mathematical theory behind the double descent behavior of model test error for varying model sizes. We quantify the model size by the ration of number of training samples to the dimension of the model. Due to the complexity of the empirical risk minimization procedure, we use the Convex Gaussian MinMax Theorem to find a suitable candidate for the global training loss.
Supplementary material
Supplementary MaterialWe have included two supplementary files where Supplementary material 1 contains detailed calculations, theorems and proofs and Supplementary material 2 contains the R/RStudio codes used to draw the curves presented in the paper.
References
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