Introduction
Attention visualization refers to techniques for visualizing and interpreting attention weights in neural networks. Attention matrices can be visualized as heatmaps showing which tokens attend to which other tokens, helping us understand what the model has learned.
Why Visualize Attention?
- Interpretability: Understand what information the model focuses on
- Debugging: Identify if model is looking at correct parts
- Insights: Discover patterns learned by the model
- Trust: Verify model is reasoning correctly
Visualization Methods
1. Attention Heatmap
Matrix visualization where color intensity shows attention weight:
Rows: query positions
Columns: key positions
Color: attention weight (darker = higher)
Columns: key positions
Color: attention weight (darker = higher)
2. Edge Drawing
Draw lines from attending token to attended token, with thickness indicating weight.
3. Token Highlighting
Highlight source tokens by how much they're attended to.
Attention Patterns to Look For
| Pattern | What it indicates |
|---|---|
| Diagonal | Local structure (adjacent tokens attend) |
| Vertical [CLS] | CLS token aggregating information |
| Strong connections | Syntactic/semantic relationships |
| Uniform | Model may not be learning meaningful patterns |
Tools for Visualization
- Transformers library: attention visualization utilities
- exBERT: Interactive visualization tool
- TensorBoard: Attention logging
- Custom plots: matplotlib/seaborn heatmaps