title: The CoT Encyclopedia: Analyzing, Predicting, and Controlling how a
    Reasoning Model will Think
summary: Long chain-of-thought (CoT) is an essential ingredient in effective usage of
  modern large language models, but our understanding of the reasoning strategies
  underlying these capabilities remains limited. While some prior works have
  attempted to categorize CoTs using predefined strategy types, such approaches
  are constrained by human intuition and fail to capture the full diversity of
  model behaviors. In this work, we introduce the CoT Encyclopedia, a bottom-up
  framework for analyzing and steering model reasoning. Our method automatically
  extracts diverse reasoning criteria from model-generated CoTs, embeds them into
  a semantic space, clusters them into representative categories, and derives
  contrastive rubrics to interpret reasoning behavior. Human evaluations show
  that this framework produces more interpretable and comprehensive analyses than
  existing methods. Moreover, we demonstrate that this understanding enables
  performance gains: we can predict which strategy a model is likely to use and
  guide it toward more effective alternatives. Finally, we provide practical
  insights, such as that training data format (e.g., free-form vs.
  multiple-choice) has a far greater impact on reasoning behavior than data
  domain, underscoring the importance of format-aware model design.
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paper_authors.name: Seongyun Lee
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paper_authors.name: Yongrae Jo
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paper_authors.fullname: Yongrae Jo
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paper_authors.name: Dongyoung Go
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paper_authors.name: Hyeonbin Hwang
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paper_authors.fullname: Hyeonbin Hwang 
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paper_authors.name: Jinho Park
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paper_authors.fullname: Jinho Park
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paper_authors.user: Br3ad
paper_authors._id: 68269f67a47cb2b87646b993
paper_authors.name: Xiang Yue
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paper_authors.name: Sean Welleck
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paper_authors.fullname: Sean Welleck
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paper_authors.name: Graham Neubig
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paper_authors.fullname: Graham Neubig
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paper_authors.name: Moontae Lee
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paper_title: The CoT Encyclopedia: Analyzing, Predicting, and Controlling how a
    Reasoning Model will Think
paper_summary: Long chain-of-thought (CoT) is an essential ingredient in effective usage of
  modern large language models, but our understanding of the reasoning strategies
  underlying these capabilities remains limited. While some prior works have
  attempted to categorize CoTs using predefined strategy types, such approaches
  are constrained by human intuition and fail to capture the full diversity of
  model behaviors. In this work, we introduce the CoT Encyclopedia, a bottom-up
  framework for analyzing and steering model reasoning. Our method automatically
  extracts diverse reasoning criteria from model-generated CoTs, embeds them into
  a semantic space, clusters them into representative categories, and derives
  contrastive rubrics to interpret reasoning behavior. Human evaluations show
  that this framework produces more interpretable and comprehensive analyses than
  existing methods. Moreover, we demonstrate that this understanding enables
  performance gains: we can predict which strategy a model is likely to use and
  guide it toward more effective alternatives. Finally, we provide practical
  insights, such as that training data format (e.g., free-form vs.
  multiple-choice) has a far greater impact on reasoning behavior than data
  domain, underscoring the importance of format-aware model design.
paper_ai_summary: The CoT Encyclopedia is a bottom-up framework that automatically analyzes and categorizes reasoning strategies in long chain-of-thoughts generated by large language models, providing more interpretable analyses and enabling performance improvements.
paper_ai_keywords: long chain-of-thought modern large language models reasoning strategies CoT Encyclopedia semantic space clusters contrastive rubrics free-form vs. multiple-choice format-aware model design