# Provable Benefits of Overparameterization in Model Compression: From Double Descent to Pruning Neural Networks

arXiv: https://arxiv.org/abs/2012.08749 · HTML: https://mlsanity.com/paper/2012.08749/

## Key facts

- Cited by 40 papers in the map (data through 14 Oct 2026).
- First posted on arXiv 16 Dec 2020.

## Built on by (most cited first, 30 of 40)

- [Label-Imbalanced and Group-Sensitive Classification under Overparameterization](https://mlsanity.com/paper/2103.01550/) (2021)
- [A Farewell to the Bias-Variance Tradeoff? An Overview of the Theory of Overparameterized Machine Learning](https://mlsanity.com/paper/2109.02355/) (2021)
- [MergeBench: A Benchmark for Merging Domain-Specialized LLMs](https://mlsanity.com/paper/2505.10833/) (2025)
- [Sparse Double Descent: Where Network Pruning Aggravates Overfitting](https://mlsanity.com/paper/2206.08684/) (2022)
- [Why Random Pruning Is All We Need to Start Sparse](https://mlsanity.com/paper/2210.02412/) (2022)
- [Precise Asymptotic Analysis of Deep Random Feature Models](https://mlsanity.com/paper/2302.06210/) (2023)
- [High-dimensional Analysis of Knowledge Distillation: Weak-to-Strong Generalization and Scaling Laws](https://mlsanity.com/paper/2410.18837/) (2024)
- [Towards Sample-efficient Overparameterized Meta-learning](https://mlsanity.com/paper/2201.06142/) (2022)
- [Masks, Signs, And Learning Rate Rewinding](https://mlsanity.com/paper/2402.19262/) (2024)
- [Generalization Guarantees for Neural Architecture Search with Train-Validation Split](https://mlsanity.com/paper/2104.14132/) (2021)
- [Provable and Efficient Continual Representation Learning](https://mlsanity.com/paper/2203.02026/) (2022)
- [Lottery Jackpots Exist in Pre-trained Models](https://mlsanity.com/paper/2104.08700/) (2021)
- [Strong inductive biases provably prevent harmless interpolation](https://mlsanity.com/paper/2301.07605/) (2023)
- [Spurious Correlations in High Dimensional Regression: The Roles of Regularization, Simplicity Bias and Over-Parameterization](https://mlsanity.com/paper/2502.01347/) (2025)
- [Deep Double Descent via Smooth Interpolation](https://mlsanity.com/paper/2209.10080/) (2022)
- [Distilling Double Descent](https://mlsanity.com/paper/2102.06849/) (2021)
- [High-dimensional Analysis of Synthetic Data Selection](https://mlsanity.com/paper/2510.08123/) (2025)
- [DSD2: Can We Dodge Sparse Double Descent and Compress the Neural Network Worry-Free?](https://mlsanity.com/paper/2303.01213/) (2023)
- [Unraveling the Enigma of Double Descent: An In-depth Analysis through the Lens of Learned Feature Space](https://mlsanity.com/paper/2310.13572/) (2023)
- [How much pre-training is enough to discover a good subnetwork?](https://mlsanity.com/paper/2108.00259/) (2021)
- [Deep Architecture Connectivity Matters for Its Convergence: A Fine-Grained Analysis](https://mlsanity.com/paper/2205.05662/) (2022)
- [Spectral Pruning for Recurrent Neural Networks](https://mlsanity.com/paper/2105.10832/) (2021)
- [Random Features Model with General Convex Regularization: A Fine Grained Analysis with Precise Asymptotic Learning Curves](https://mlsanity.com/paper/2204.02678/) (2022)
- [Efficient Compression of Overparameterized Deep Models through Low-Dimensional Learning Dynamics](https://mlsanity.com/paper/2311.05061/) (2023)
- [Accelerating Linear Recurrent Neural Networks for the Edge with Unstructured Sparsity](https://mlsanity.com/paper/2502.01330/) (2025)
- [Can we avoid Double Descent in Deep Neural Networks?](https://mlsanity.com/paper/2302.13259/) (2023)
- [Precise asymptotics of reweighted least-squares algorithms for linear diagonal networks](https://mlsanity.com/paper/2406.02769/) (2024)
- [Overparameterization from Computational Constraints](https://mlsanity.com/paper/2208.12926/) (2022)
- [Implicit Bias in Matrix Factorization and its Explicit Realization in a New Architecture](https://mlsanity.com/paper/2501.16322/) (2025)
- [Optimal Implicit Bias in Linear Regression](https://mlsanity.com/paper/2506.17187/) (2025)

## Abstract (arXiv)

Deep networks are typically trained with many more parameters than the size of the training dataset. Recent empirical evidence indicates that the practice of overparameterization not only benefits training large models, but also assists - perhaps counterintuitively - building lightweight models. Specifically, it suggests that overparameterization benefits model pruning / sparsification. This paper sheds light on these empirical findings by theoretically characterizing the high-dimensional asymptotics of model pruning in the overparameterized regime. The theory presented addresses the following core question: "should one train a small model from the beginning, or first train a large model and then prune?". We analytically identify regimes in which, even if the location of the most informative features is known, we are better off fitting a large model and then pruning rather than simply training with the known informative features. This leads to a new double descent in the training of sparse models: growing the original model, while preserving the target sparsity, improves the test accuracy as one moves beyond the overparameterization threshold. Our analysis further reveals the benefit of retraining by relating it to feature correlations. We find that the above phenomena are already present in linear and random-features models. Our technical approach advances the toolset of high-dimensional analysis and precisely characterizes the asymptotic distribution of over-parameterized least-squares. The intuition gained by analytically studying simpler models is numerically verified on neural networks.
