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Concise Thoughts: Impact of Output Length on LLM Reasoning and Cost

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arxiv 2407.19825 v2 pith:3E4QNBUH submitted 2024-07-29 cs.CL cs.AI

Concise Thoughts: Impact of Output Length on LLM Reasoning and Cost

classification cs.CL cs.AI
keywords concisenessimpactmodelsoutputprompttechniquesanswersccot
verification ladder T0 review T1 audit T2 compute T3 formal T4 reserved
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Today's large language models (LLMs) can solve challenging question-answering tasks, and prompt engineering techniques, such as chain-of-thought (CoT), have gained attention for enhancing the explanation and correctness of outputs. However, many models and techniques tend to produce excessively verbose and lengthy answers, leading to issues with both conciseness and generation time. To address this, this paper analyzes the impact of output lengths on LLM inference pipelines by introducing and proposing novel metrics to evaluate the \textit{correct conciseness} of a model and related prompting techniques. Then, we examine the impact of controlling output length through a refined prompt engineering strategy, Constrained-CoT (CCoT), which encourages the model to produce more concise outputs. To better understand the effects of such a prompt, we also introduce two additional scores for analyzing the conciseness, measured in terms of redundancy and information flow in generated answers. Experiments on pretrained LLMs and multiple datasets demonstrate the benefits of the proposed metrics and the effectiveness of CCoT across different models.

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Cited by 17 Pith papers

Reviewed papers in the Pith corpus that reference this work. Sorted by Pith novelty score.

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