Adaptive Optimizers with Sparse Group Lasso for Neural Networks in CTR Prediction
Yun Yue, Yongchao Liu, Suo Tong, Minghao Li, Zhen Zhang, Chunyang Wen, Huanjun Bao, Lihong Gu, Jinjie Gu, Yixiang Mu
TL;DR
This work introduces a framework that integrates sparse group lasso regularization into a broad family of adaptive optimizers for neural networks, enabling direct sparsity in DNNs without post-processing. It derives a closed-form ada-group-lasso update and shows how Group Adam and Group Adagrad extend existing optimizers while preserving their baseline behavior when regularizers are zero. The authors establish regret bounds and convergence rates in the online convex optimization setting, proving an $O(\sqrt{T})$ regret under suitable conditions. Empirically, the proposed Group variants outperform their vanilla counterparts at equivalent sparsity on three large CTR datasets, achieving substantial sparsity with competitive or improved AUC, and enabling high sparsity with strong performance. The work provides publicly available code and highlights practical insights for hyperparameter choices and embedding-dimension effects in sparse CTR models.
Abstract
We develop a novel framework that adds the regularizers of the sparse group lasso to a family of adaptive optimizers in deep learning, such as Momentum, Adagrad, Adam, AMSGrad, AdaHessian, and create a new class of optimizers, which are named Group Momentum, Group Adagrad, Group Adam, Group AMSGrad and Group AdaHessian, etc., accordingly. We establish theoretically proven convergence guarantees in the stochastic convex settings, based on primal-dual methods. We evaluate the regularized effect of our new optimizers on three large-scale real-world ad click datasets with state-of-the-art deep learning models. The experimental results reveal that compared with the original optimizers with the post-processing procedure which uses the magnitude pruning method, the performance of the models can be significantly improved on the same sparsity level. Furthermore, in comparison to the cases without magnitude pruning, our methods can achieve extremely high sparsity with significantly better or highly competitive performance. The code is available at https://github.com/intelligent-machine-learning/tfplus/tree/main/tfplus.
