Title
Neural Collaborative Filtering vs. Matrix Factorization Revisited
Abstract
ABSTRACT Embedding based models have been the state of the art in collaborative filtering for over a decade. Traditionally, the dot product or higher order equivalents have been used to combine two or more embeddings, e.g., most notably in matrix factorization. In recent years, it was suggested to replace the dot product with a learned similarity e.g. using a multilayer perceptron (MLP). This approach is often referred to as neural collaborative filtering (NCF). In this work, we revisit the experiments of the NCF paper that popularized learned similarities using MLPs. First, we show that with a proper hyperparameter selection, a simple dot product substantially outperforms the proposed learned similarities. Second, while a MLP can in theory approximate any function, we show that it is non-trivial to learn a dot product with an MLP. Finally, we discuss practical issues that arise when applying MLP based similarities and show that MLPs are too costly to use for item recommendation in production environments while dot products allow to apply very efficient retrieval algorithms. We conclude that MLPs should be used with care as embedding combiner and that dot products might be a better default choice.
Year
DOI
Venue
2020
10.1145/3383313.3412488
RECSYS
DocType
Citations 
PageRank 
Conference
16
0.49
References 
Authors
16
4
Name
Order
Citations
PageRank
Steffen Rendle1116138.28
Walid Krichene210814.02
Zhang Li3160.49
John Anderson4427.10