Lattice-Based Pruning in Recurrent Neural Networks via Poset Modeling
Rakesh Sengupta
TL;DR
This work addresses the computational burden of recurrent neural networks by introducing a poset-based lattice framework for pruning. By modeling RNNs as dependency lattices and identifying meet-irreducible elements (and centrality), it guides pruning while preserving essential connectivity, using both binary and continuous adjacency representations. The authors provide thorough complexity analyses for hierarchical multilayer RNNs and validate the approach on MNIST with LSTM, revealing a trade-off: binary adjacency yields ~50% sparsity with >98% accuracy, while continuous adjacency achieves near-total sparsity with noticeable accuracy loss. The framework offers a rigorous, scalable path to efficient, hierarchical RNNs and has potential implications for computational neuroscience and machine learning applications requiring real-time performance.
Abstract
Recurrent neural networks (RNNs) are central to sequence modeling tasks, yet their high computational complexity poses challenges for scalability and real-time deployment. Traditional pruning techniques, predominantly based on weight magnitudes, often overlook the intrinsic structural properties of these networks. We introduce a novel framework that models RNNs as partially ordered sets (posets) and constructs corresponding dependency lattices. By identifying meet irreducible neurons, our lattice-based pruning algorithm selectively retains critical connections while eliminating redundant ones. The method is implemented using both binary and continuous-valued adjacency matrices to capture different aspects of network connectivity. Evaluated on the MNIST dataset, our approach exhibits a clear trade-off between sparsity and classification accuracy. Moderate pruning maintains accuracy above 98%, while aggressive pruning achieves higher sparsity with only a modest performance decline. Unlike conventional magnitude-based pruning, our method leverages the structural organization of RNNs, resulting in more effective preservation of functional connectivity and improved efficiency in multilayer networks with top-down feedback. The proposed lattice-based pruning framework offers a rigorous and scalable approach for reducing RNN complexity while sustaining robust performance, paving the way for more efficient hierarchical models in both machine learning and computational neuroscience.
