Apple ML ★ 100 4 min

Selection-Based Structured Reasoning: Toward Efficient Multimodal Search Agents

🔗 https://machinelearning.apple.com/research/selection-structured-reasoning

📌 小模型不用寫長篇推理,選選項就好:Apple的SSR框架

TL;DR:Apple提出SSR,把agent推理從生成改成選擇,推理延遲降低逾九成。

多模態搜尋agent每次行動前都要先生成一段推理文字,但對小模型來說,這段文字常常又長又沒什麼用,還拖慢整個agent的反應速度。Apple ML的新研究給出一個反直覺的解法:別讓模型寫推理,讓它選推理。

🤔 小模型的推理,常常是又長又沒用 多模態agent通常會在每個action之前生成freeform(開放式)的推理文字。但對小模型而言,有限的模型容量常常導致生成出來的推理冗長,卻沒辦法為後續的action提供多少有用的引導,同時還會拉高推理成本。

🧩 把「生成推理」改成「選擇推理」 Apple ML提出的Selection-based Structured Reasoning(SSR)框架,把推理重新定義為「選擇」而不是「開放式生成」。具體做法是:把常見的高層次推理預先定義成一組可重複使用的自然語言候選(pre-specified, reusable natural-language candidates)。每一輪,模型會根據目前的context,依據這些候選的likelihood來做選擇,而且不需要額外的輔助任務頭(auxiliary task head)。由於推理候選是事先指定好的,SSR可以用teacher-forced prefilling同時計算候選內部與候選之間的token likelihood,並共用同一個context KV cache,實現平行評分(parallel scoring),取代原本必須逐個生成候選再比較的做法。

📊 推理延遲降低逾九成,成功率仍具競爭力 研究團隊在七個多模態搜尋benchmark上,用2B與4B兩種規模的模型測試SSR,訓練方式涵蓋多種強化學習(RL)目標與監督式微調(SFT)。結果顯示,SSR的平均成功率可以與同規模的領先搜尋agent相競爭,同時把每輪的推理延遲降低超過90%,整題的總推理延遲則降低28%到54%。

💡 把推理瓶頸從「模型容量」轉成「候選設計」 這篇研究點出一個值得留意的方向:當我們把推理看作「從有限候選中挑選」,而不是「自由生成一串token」,小模型因容量不足而寫出冗長無效推理的問題,可以透過結構化、可平行評分的方式繞開,而不必單純依賴堆大模型參數來解決。對於需要在裝置端或資源受限環境執行agent的場景,這種「推理即選擇」的思路,可能比一味追求更長的chain-of-thought更務實。

🎯 實務啟示 如果你正在設計資源受限(2B、4B等級)的多模態搜尋或agent系統,SSR提示了一個可以嘗試的方向:把常見的推理模式先枚舉成候選集合,用likelihood選擇取代生成,一方面能透過共用KV cache做平行評分省下時間,另一方面也避免小模型寫出又長又沒有引導力的推理內容。

🔗 來源

  • 標題:Selection-Based Structured Reasoning: Toward Efficient Multimodal Search Agents
  • 作者/機構:Feiyu Gavin Zhu、Xiaoyu Zhu、Jiqi Yang、Rui Yang、Arnab Kumar Mondal、Yancheng Wang、Xinke Deng、Jean Oh、Reid Simmons、Joerg Liebelt、Xiang Kong、Zhongyu Jiang(Apple ML,部分作者分別來自Carnegie Mellon University與University of Illinois Urbana-Champaign)
  • 連結:https://machinelearning.apple.com/research/selection-structured-reasoning

#AppleML #MultimodalAI #SearchAgents #StructuredReasoning #LLM #ReinforcementLearning #AIAgents #EfficientInference #MachineLearning #EdgeAI

原始資料 Apple ML · 收集於 2026-10-15
來源原標題
Selection-Based Structured Reasoning: Toward Efficient Multimodal Search Agents
原始連結
https://machinelearning.apple.com/research/selection-structured-reasoning

摘要原文

research area Methods and Algorithms content type paper published October 2026 Selection-Based Structured Reasoning: Toward Efficient Multimodal Search Agents Authors Feiyu Gavin Zhu†**, Xiaoyu Zhu, Jiqi Yang, Rui Yang‡***, Arnab Kumar Mondal, Yancheng Wang, Xinke Deng, Jean Oh†, Reid Simmons†, Joerg Liebelt, Xiang Kong, Zhongyu Jiang View publication Copy Bibtex Multimodal agents commonly generate freeform reasoning before each action. For small models, limited model capacity can result in lengthy reasoning that provides little useful guidance for action generation while incurring substantial inference cost. To address this challenge, we introduce Selection-based Structured Reasoning (SSR), a framework that reformulates reasoning as selection instead of open-ended generation. SSR represents recurring high-level reasoning as pre-specified, reusable natural-language candidates. At each turn, the model selects from the reasoning candidates based on their likelihoods given the current context, without an auxiliary task head. Using pre-specified reasoning traces enables parallel scoring, where teacher-forced prefilling computes token likelihoods concurrently within and across candidates using a shared context KV cache. We evaluated SSR on seven multimodal search benchmarks using 2B and 4B models. Across multiple reinforcement learning objectives and supervised fine-tuning, SSR delivers significant efficiency gains without sacrificing task performance. SSR achieves an average success rate competitive with leading search agents of the same scale, while reducing per-turn reasoning latency by over 90% and total per-question model inference latency by 28–54%. † Carnegie Mellon University ‡ University of Illinois Urbana-Champaign ** Work partially done while at Apple *** Work done while at Apple Related readings and updates. Learning Structured Reasoning via Tractable Trajectory Control July 2, 2026 research area Computer Vision , research area Speech and Natural Language Processing conference ICML Large language models can exhibit emergent reasoning behaviors, often manifested as recurring lexical patterns (e.g., “wait,” indicating verification). However, complex reasoning trajectories remain sparse in unconstrained sampling, and standard RL often fails to guarantee the acquisition of diverse reasoning behaviors. We propose a systematic discovery and reinforcement of diverse reasoning patterns through structured reasoning, a paradigm that… Read more Interleaved Reasoning for Large Language Models via Reinforcement Learning May 28, 2025 research area Knowledge Bases and Search , research area Speech and Natural Language Processing Long chain-of-thought (CoT) significantly enhances large language models’ (LLM) reasoning capabilities. However, the extensive reasoning traces lead to inefficiencies and an increased time-to-first-token (TTFT). We propose a novel training paradigm that uses reinforcement learning (RL) to guide reasoning LLMs to interleave thinking and answering for multi-hop questions. We observe that models inherently possess the ability to perform interleaved… Read more Discover opportunities in Machine Learning. Our research in machine learning breaks new ground every day. Work with us

由 claude-code/sonnet 自動生成