When Do Graph Foundation Models Transfer? A Data-Centric Theory
Summary
Graph foundation models (GFMs) often exhibit uneven or negative transfer when applied across different graph domains, despite their goal of reusing a single backbone. This research investigates the data-centric properties that dictate how a fixed representation model's outputs shift between domains. Utilizing a graphon-based continuous limit for dense graphs, the study demonstrates that for both set-based and message-passing tokenizations, any Lipschitz backbone allows an explicit decomposition of cross-domain output shift. This decomposition comprises graph-specific finite-sample approximation terms and an intrinsic, relabeling-invariant domain discrepancy reflecting structural mismatch. A critical component is positional-encoding (PE) stability, with the work establishing stability guarantees for spectral PEs and highlighting distinct behaviors between eigenvector- and subspace-based PEs. Experiments on synthetic and real graphs confirm the theory and offer guidance for data curation in GFM transfer.
Key takeaway
For Machine Learning Engineers developing or deploying Graph Foundation Models, understanding the data-centric theory of transfer is critical. You should analyze the intrinsic domain discrepancy and positional encoding stability between source and target graphs to predict transfer success and mitigate negative transfer. This framework provides guidance for curating training data and selecting appropriate PEs, directly impacting your model's cross-domain performance.
Key insights
GFM transfer shift can be explicitly decomposed into finite-sample approximation and intrinsic domain discrepancy, guided by positional encoding stability.
Principles
- GFM transfer behavior is determined by data domain properties.
- Output shift decomposes into finite-sample and domain discrepancy.
- Positional encoding stability is key for GFM transfer.
Method
The study employs a graphon-based continuous limit for dense graphs to derive an explicit decomposition of cross-domain output shift for Lipschitz backbones.
In practice
- Guide data curation for improved GFM transfer.
- Analyze domain discrepancy to predict transfer success.
- Evaluate PE stability for GFM architecture design.
Topics
- Graph Foundation Models
- Transfer Learning
- Data-Centric AI
- Graphons
- Positional Encoding
- Domain Discrepancy
Best for: Research Scientist, AI Scientist, Machine Learning Engineer
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Editorial summary, takeaway, and curation by AIssential. Original article published by Machine Learning.