Bidding-Aware Retrieval for Multi-Stage Consistency in Online Advertising

TL;DR

This paper introduces Bidding-Aware Retrieval (BAR), a novel framework that integrates bid signals into ad retrieval to improve revenue and impression metrics in online advertising systems with multi-stage cascaded architectures.

Contribution

The paper presents a new Bidding-Aware Modeling approach with monotonicity constraints and multi-task distillation, along with asynchronous inference and feature refinement modules, to address multi-stage inconsistency in ad retrieval.

Findings

Achieved 4.32% revenue increase in Alibaba's platform.

Realized 22.2% impression lift for targeted ads.

Validated effectiveness through extensive offline and online experiments.

Abstract

Online advertising systems typically use a cascaded architecture to manage massive requests and candidate volumes, where the ranking stages allocate traffic based on eCPM (predicted CTR $\times$ Bid). With the increasing popularity of auto-bidding strategies, the inconsistency between the computationally sensitive retrieval stage and the ranking stages becomes more pronounced, as the former cannot access precise, real-time bids for the vast ad corpus. This discrepancy leads to sub-optimal platform revenue and advertiser outcomes. To tackle this problem, we propose Bidding-Aware Retrieval (BAR), a model-based retrieval framework that addresses multi-stage inconsistency by incorporating ad bid value into the retrieval scoring function. The core innovation is Bidding-Aware Modeling, incorporating bid signals through monotonicity-constrained learning and multi-task distillation to ensure economically coherent representations, while Asynchronous Near-Line Inference enables real-time updates to the embedding for market responsiveness. Furthermore, the Task-Attentive Refinement module selectively enhances feature interactions to disentangle user interest and commercial value signals. Extensive offline experiments and full-scale deployment across Alibaba's display advertising platform validated BAR's efficacy: 4.32% platform revenue increase with 22.2% impression lift for positively-operated advertisements.