Noveen Sachdeva, Mehak Preet Dhaliwal, Carole-Jean Wu, Julian McAuley
We leverage the Neural Tangent Kernel and its equivalence to training infinitely-wide neural networks to devise $\infty$-AE: an autoencoder with infinitely-wide bottleneck layers. The outcome is a highly expressive yet simplistic recommendation model with a single hyper-parameter and a closed-form solution. Leveraging $\infty$-AE's simplicity, we also develop Distill-CF for synthesizing tiny, high-fidelity data summaries which distill the most important knowledge from the extremely large and sparse user-item interaction matrix for efficient and accurate subsequent data-usage like model training, inference, architecture search, etc. This takes a data-centric approach to recommendation, where we aim to improve the quality of logged user-feedback data for subsequent modeling, independent of the learning algorithm. We particularly utilize the concept of differentiable Gumbel-sampling to handle the inherent data heterogeneity, sparsity, and semi-structuredness, while being scalable to datasets with hundreds of millions of user-item interactions. Both of our proposed approaches significantly outperform their respective state-of-the-art and when used together, we observe 96-105% of $\infty$-AE's performance on the full dataset with as little as 0.1% of the original dataset size, leading us to explore the counter-intuitive question: Is more data what you need for better recommendation?
| Task | Dataset | Metric | Value | Model |
|---|---|---|---|---|
| Recommendation Systems | Netflix | AUC | 0.9728 | ∞-AE |
| Recommendation Systems | Netflix | PSP@10 | 0.0375 | ∞-AE |
| Recommendation Systems | Netflix | Recall@10 | 0.2969 | ∞-AE |
| Recommendation Systems | Netflix | Recall@100 | 0.5088 | ∞-AE |
| Recommendation Systems | Netflix | nDCG@10 | 0.3059 | ∞-AE |
| Recommendation Systems | Netflix | nDCG@100 | 0.3659 | ∞-AE |
| Recommendation Systems | MovieLens 1M | HR@10 | 0.3151 | ∞-AE |
| Recommendation Systems | MovieLens 1M | HR@100 | 0.6005 | ∞-AE |
| Recommendation Systems | MovieLens 1M | PSP@10 | 0.0322 | ∞-AE |
| Recommendation Systems | MovieLens 1M | nDCG@10 | 0.3282 | ∞-AE |
| Recommendation Systems | MovieLens 1M | nDCG@100 | 0.4253 | ∞-AE |
| Recommendation Systems | Douban | AUC | 0.9523 | ∞-AE |
| Recommendation Systems | Douban | HR@10 | 0.2356 | ∞-AE |
| Recommendation Systems | Douban | HR@100 | 0.2837 | ∞-AE |
| Recommendation Systems | Douban | PSP@10 | 0.0128 | ∞-AE |
| Recommendation Systems | Douban | nDCG@10 | 0.2494 | ∞-AE |
| Recommendation Systems | Douban | nDCG@100 | 0.2326 | ∞-AE |