Customer Preference Learning with Zero-Initialized Distance and Embedding Fusion (ZIP-EF)

Abstract
Recommender systems play a key role in online shopping and constitute a major component of user interaction on e-commerce platforms. Classical recommendation approaches rely on fixed similarity metrics, such as cosine similarity or Euclidean distance between textual and visual embeddings, which limits their ability to adapt to dynamic and personalized user preferences. This paper proposes a multimodal recommendation framework in which the distance function between user and product embeddings is fully learnable. Textual and visual embeddings are combined using element-wise learnable fusion, and a bidirectional multilayer perceptron with GELU activation projects embeddings into a preference-oriented latent space. An interaction layer extracts four complementary representations, including user features, item features, their element-wise difference, and their element-wise product, following neural collaborative filtering paradigms. The metric layer is initialized to exactly reproduce cosine similarity, ensuring stable performance at initialization, and is subsequently adapted through pairwise preference learning. User click behavior is transformed into preference pairs, enabling the model to assign higher similarity to preferred items and lower similarity to ignored ones. Experimental results demonstrate that the proposed approach achieves stable and progressive personalization, providing greater adaptability to real user behavior than fixed-metric recommendation methods.
Keywords

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