Real-Time Trend Prediction via Continually-Aligned LLM Query Generation
Zijing Hui, Wenhan Lyu, Shusen Wang, Li Chen, Chu Wang
TL;DR
RTTP tackles the cold-start problem in real-time trend detection by generating synthetic search queries directly from new posts using a continually updated LLM (CL-LLM). It introduces Mix-Policy DPO to balance on-policy stability with off-policy novelty, mitigating catastrophic forgetting during continual updates. In production on Facebook and Meta AI platforms, RTTP achieves substantial gains in tail-trend precision (~+91.4% at ranking 500) and query-generation accuracy (~+19%), while maintaining stability over multi-week online training. The work demonstrates that aligned, continually updated synthetic signals can enable timely trend understanding in low-traffic search environments.
Abstract
Trending news detection in low-traffic search environments faces a fundamental cold-start problem, where a lack of query volume prevents systems from identifying emerging or long-tail trends. Existing methods relying on keyword frequency or query spikes are inherently slow and ineffective in these sparse settings, lagging behind real-world shifts in attention. We introduce RTTP, a novel Real-Time Trending Prediction framework that generates search queries directly from news content instead of waiting for users to issue them. RTTP leverages a continual learning LLM (CL-LLM) that converts posts into search-style queries and scores them using engagement strength + creator authority, enabling early trend surfacing before search volume forms. To ensure adaptation without degrading reasoning, we propose Mix-Policy DPO, a new preference-based continual learning approach that combines on-policy stability with off-policy novelty to mitigate catastrophic forgetting during model upgrades. Deployed at production scale on Facebook and Meta AI products, RTTP delivers +91.4% improvement in tail-trend detection precision@500 and +19% query generation accuracy over industry baselines, while sustaining stable performance after multi-week online training. This work demonstrates that LLM-generated synthetic search signals, when aligned and continually updated, unlock timely trend understanding in low-traffic search environments.
