# Deep Neural Network Initialization with Sparsity Inducing Activations

arXiv: https://arxiv.org/abs/2402.16184 · HTML: https://mlsanity.com/paper/2402.16184/

## Key facts

- Cited by 5 papers in the map (data through 14 Oct 2026).
- Builds on 21 of its 24 references that are in the map.
- First posted on arXiv 25 Feb 2024.

## Builds on (most cited first, 21 of 21)

- [Learning both Weights and Connections for Efficient Neural Networks](https://mlsanity.com/paper/1506.02626/) (2015)
- [SNIP: Single-shot Network Pruning based on Connection Sensitivity](https://mlsanity.com/paper/1810.02340/) (2018)
- [Deep Neural Networks as Gaussian Processes](https://mlsanity.com/paper/1711.00165/) (2017)
- [What is the State of Neural Network Pruning?](https://mlsanity.com/paper/2003.03033/) (2020)
- [Sparsity in Deep Learning: Pruning and growth for efficient inference and training in neural networks](https://mlsanity.com/paper/2102.00554/) (2021)
- [Pruning neural networks without any data by iteratively conserving synaptic flow](https://mlsanity.com/paper/2006.05467/) (2020)
- [Exponential expressivity in deep neural networks through transient chaos](https://mlsanity.com/paper/1606.05340/) (2016)
- [Deep Information Propagation](https://mlsanity.com/paper/1611.01232/) (2016)
- [Dynamical Isometry and a Mean Field Theory of CNNs: How to Train 10,000-Layer Vanilla Convolutional Neural Networks](https://mlsanity.com/paper/1806.05393/) (2018)
- [The Principles of Deep Learning Theory](https://mlsanity.com/paper/2106.10165/) (2021)
- [Resurrecting the sigmoid in deep learning through dynamical isometry: theory and practice](https://mlsanity.com/paper/1711.04735/) (2017)
- [Mean Field Residual Networks: On the Edge of Chaos](https://mlsanity.com/paper/1712.08969/) (2017)
- [The Emergence of Spectral Universality in Deep Networks](https://mlsanity.com/paper/1802.09979/) (2018)
- [A Mean Field Theory of Batch Normalization](https://mlsanity.com/paper/1902.08129/) (2019)
- [Dynamical Isometry and a Mean Field Theory of RNNs: Gating Enables Signal Propagation in Recurrent Neural Networks](https://mlsanity.com/paper/1806.05394/) (2018)
- [Accelerating Convolutional Neural Networks via Activation Map Compression](https://mlsanity.com/paper/1812.04056/) (2018)
- [Robust Pruning at Initialization](https://mlsanity.com/paper/2002.08797/) (2020)
- [Dynamical Isometry and a Mean Field Theory of LSTMs and GRUs](https://mlsanity.com/paper/1901.08987/) (2019)
- [Activation function design for deep networks: linearity and effective initialisation](https://mlsanity.com/paper/2105.07741/) (2021)
- [Sparsely Activated Networks](https://mlsanity.com/paper/1907.06592/) (2019)
- [Mean field theory for deep dropout networks: digging up gradient backpropagation deeply](https://mlsanity.com/paper/1912.09132/) (2019)

## Built on by (most cited first, 5 of 5)

- [Bayesian Inference with Deep Weakly Nonlinear Networks](https://mlsanity.com/paper/2405.16630/) (2024)
- [DiGRAF: Diffeomorphic Graph-Adaptive Activation Function](https://mlsanity.com/paper/2407.02013/) (2024)
- [How Controlling the Variance can Improve Training Stability of Sparsely Activated DNNs and CNNs](https://mlsanity.com/paper/2602.05779/) (2026)
- [Low-Latency Activation-Regularized Sparse Neural Operators with Distillation Assistance Towards Real-Time Neuromorphic Virtual Sensing](https://mlsanity.com/paper/2608.23987/) (2026)
- [Beyond Gaussian Initializations: Signal Preserving Weight Initialization for Odd-Sigmoid Activations](https://mlsanity.com/paper/2509.23085/) (2025)

## Abstract (arXiv)

Inducing and leveraging sparse activations during training and inference is a promising avenue for improving the computational efficiency of deep networks, which is increasingly important as network sizes continue to grow and their application becomes more widespread. Here we use the large width Gaussian process limit to analyze the behaviour, at random initialization, of nonlinear activations that induce sparsity in the hidden outputs. A previously unreported form of training instability is proven for arguably two of the most natural candidates for hidden layer sparsification; those being a shifted ReLU (φ(x)=max(0, x-τ) for τ≥ 0) and soft thresholding (φ(x)=0 for |x|≤τ and x-sign(x)τ for |x|>τ). We show that this instability is overcome by clipping the nonlinear activation magnitude, at a level prescribed by the shape of the associated Gaussian process variance map. Numerical experiments verify the theory and show that the proposed magnitude clipped sparsifying activations can be trained with training and test fractional sparsity as high as 85% while retaining close to full accuracy.
