The Sparse Tsetlin Machine: Sparse Representation with Active Literals
Sebastian Østby, Tobias M. Brambo, Sondre Glimsdal
TL;DR
The paper tackles the inefficiency of traditional Tsetlin Machines when handling sparse data by introducing the Sparse Tsetlin Machine (STM) and Active Literals (AL). By combining CSR-based input, per-class AL gatekeeping, and a dynamically pruned sparse memory space, STM focuses resources on discriminative literals and discards irrelevant zeros and negations. Empirical results across eight datasets show competitive accuracy with substantial improvements in memory and training efficiency, and successful deployment on large-scale text corpora demonstrates practical scalability. Overall, STM offers a principled, interpretable, and scalable approach to sparse clause representation for rule-based learning.
Abstract
This paper introduces the Sparse Tsetlin Machine (STM), a novel Tsetlin Machine (TM) that processes sparse data efficiently. Traditionally, the TM does not consider data characteristics such as sparsity, commonly seen in NLP applications and other bag-of-word-based representations. Consequently, a TM must initialize, store, and process a significant number of zero values, resulting in excessive memory usage and computational time. Previous attempts at creating a sparse TM have predominantly been unsuccessful, primarily due to their inability to identify which literals are sufficient for TM training. By introducing Active Literals (AL), the STM can focus exclusively on literals that actively contribute to the current data representation, significantly decreasing memory footprint and computational time while demonstrating competitive classification performance.
