knowledge distillation variants
**Knowledge Distillation Variants** are **extensions of the original Hinton et al. (2015) teacher-student distillation framework** — encompassing different ways to transfer knowledge from a larger model to a smaller one, including response-based, feature-based, and relation-based approaches.
**Major Variants**
- **Response-Based**: Student mimics teacher's soft output probabilities (original KD). Loss: KL divergence on softened logits.
- **Feature-Based** (FitNets): Student mimics teacher's intermediate feature representations. Requires projection layers for dimension matching.
- **Relation-Based** (RKD): Student preserves the relational structure (distances, angles) between samples as computed by the teacher.
- **Attention Transfer**: Student mimics teacher's attention maps (spatial or channel attention).
**Why It Matters**
- **Flexibility**: Different variants are optimal for different architectures and tasks.
- **Complementary**: Multiple distillation signals can be combined for stronger compression.
- **Scale**: Used to compress billion-parameter LLMs into practical deployment-sized models.
**Knowledge Distillation Variants** are **the different channels of knowledge transfer** — each capturing a different aspect of what the teacher model knows.