A Unified Search and Recommendation Framework Based on Multi-Scenario Learning for Ranking in E-commerce

TL;DR

This paper introduces a unified framework for search and recommendation in e-commerce that effectively captures scenario-specific and global label information, significantly improving multi-scenario model performance.

Contribution

The paper proposes a novel USR framework with dedicated layers for user interest and feature extraction, and a global label space multi-task layer, enhancing multi-scenario ranking models.

Findings

Significant performance improvements on real-world datasets.

Effective deployment in the 7Fresh App.

Substantial online A/B testing gains.

Abstract

Search and recommendation (S&R) are the two most important scenarios in e-commerce. The majority of users typically interact with products in S&R scenarios, indicating the need and potential for joint modeling. Traditional multi-scenario models use shared parameters to learn the similarity of multiple tasks, and task-specific parameters to learn the divergence of individual tasks. This coarse-grained modeling approach does not effectively capture the differences between S&R scenarios. Furthermore, this approach does not sufficiently exploit the information across the global label space. These issues can result in the suboptimal performance of multi-scenario models in handling both S&R scenarios. To address these issues, we propose an effective and universal framework for Unified Search and Recommendation (USR), designed with S&R Views User Interest Extractor Layer (IE) and S&R Views Feature Generator Layer (FG) to separately generate user interests and scenario-agnostic feature representations for S&R. Next, we introduce a Global Label Space Multi-Task Layer (GLMT) that uses global labels as supervised signals of auxiliary tasks and jointly models the main task and auxiliary tasks using conditional probability. Extensive experimental evaluations on real-world industrial datasets show that USR can be applied to various multi-scenario models and significantly improve their performance. Online A/B testing also indicates substantial performance gains across multiple metrics. Currently, USR has been successfully deployed in the 7Fresh App.