Poster Presentation: PDEBench-Lang: Does notation formation shape neural reasoning about PDEs?

Date:

Presented a research poster titled “PDEBench-Lang: Does notation formation shape neural reasoning about PDEs?”, investigating how symbolic representation impacts language model reasoning.

Summary

This work studies whether the notation used to represent partial differential equations (PDEs) affects how well language models understand and generalize. While prior work showed LLMs can accelerate PDE solving, the choice of notation (e.g., Postfix) was never rigorously evaluated. We systematically test whether representation format influences reasoning performance.

Approach

  • Constructed a synthetic dataset of 12,000 PDE instances across 6 families
  • Each PDE encoded in 4 symbolic dialects:
    • LaTeX
    • Prefix
    • Postfix
    • Natural Language
  • Applied data augmentations:
    • k-scaling
    • directional shuffling
    • positional shuffling
  • Trained BART-base models (one per dialect)
  • Evaluated in:
    • In-dialect setting (train/test on same format)
    • Cross-dialect setting (train/test across formats, full 4×4 matrix)
  • Metrics:
    • Family Accuracy
    • Operator F1
    • Trash Score (invalid/meaningless outputs)

Key Results

  • Models achieve 100% accuracy in-dialect, but cross-dialect generalization collapses to 13–35% :contentReference[oaicite:0]{index=0}
  • Postfix notation generalizes best, maintaining stable performance across formats
  • Natural language captures operator structure (~80% F1) even when failing classification
  • Mismatched formats produce high trash scores (up to 77%), indicating breakdown in reasoning rather than simple errors :contentReference[oaicite:1]{index=1}

Key Insights

  • Representation format strongly affects reasoning, not just performance
  • Models tend to learn format-specific patterns instead of underlying PDE structure
  • Postfix is more transferable because:
    • Eliminates parentheses and precedence tracking
    • Enforces consistent left-to-right computation
    • Produces simpler tokenization
  • Natural language provides semantic signals but weaker structural consistency

Baseline

  • Zero-shot BART achieves ~16.7% accuracy (random chance) across all formats, confirming the task requires learning and is not trivially solved :contentReference[oaicite:2]{index=2}

Contributions

  • Introduced a novel PDE symbolic reasoning benchmark (12K samples, 4 dialects)
  • Provided the first systematic study of notation effects on neural reasoning
  • Demonstrated that Postfix representation yields the strongest cross-format generalization

Impact

This work highlights that representation design is a critical factor in machine reasoning, with implications for:

  • Scientific machine learning
  • Symbolic reasoning systems
  • LLM-based equation solving

Poster PDFs

📄 Presentation Report 1

📄 Presentation Report 2

Poster Photos

Here is my picture for the poster presentation:

Poster Presentation Group Poster Presentation Individual