Turbo-CF: Matrix Decomposition-Free Graph Filtering for Fast Recommendation
Jin-Duk Park, Yong-Min Shin, Won-Yong Shin
TL;DR
This paper tackles the computational bottleneck of graph-filtering based collaborative filtering by eliminating the need for matrix decompositions. It introduces Turbo-CF, a training-free and matrix-decomposition-free method that uses polynomial graph filters on an asymmetrically normalized item-item graph to realize low-pass filtering. By carefully designing edge weights and restricting to low-order polynomial filters, Turbo-CF achieves sub-second runtimes on real-world datasets while delivering competitive recommendation accuracy. The approach leverages GPU-friendly matrix multiplications and offers a practical, scalable baseline for real-time recommendations in dynamic environments.
Abstract
A series of graph filtering (GF)-based collaborative filtering (CF) showcases state-of-the-art performance on the recommendation accuracy by using a low-pass filter (LPF) without a training process. However, conventional GF-based CF approaches mostly perform matrix decomposition on the item-item similarity graph to realize the ideal LPF, which results in a non-trivial computational cost and thus makes them less practical in scenarios where rapid recommendations are essential. In this paper, we propose Turbo-CF, a GF-based CF method that is both training-free and matrix decomposition-free. Turbo-CF employs a polynomial graph filter to circumvent the issue of expensive matrix decompositions, enabling us to make full use of modern computer hardware components (i.e., GPU). Specifically, Turbo-CF first constructs an item-item similarity graph whose edge weights are effectively regulated. Then, our own polynomial LPFs are designed to retain only low-frequency signals without explicit matrix decompositions. We demonstrate that Turbo-CF is extremely fast yet accurate, achieving a runtime of less than 1 second on real-world benchmark datasets while achieving recommendation accuracies comparable to best competitors.
