Fine Tunning methods

Self-supervised training: Foundational models are itself trained on self-supervision.

Feature based transfer learning: Embeddings from foundational models are used for other taks or train a separate models.

Infilling finetuning: Making a pre-trained autoregressive model to predict next token or middle tokens based on before or after tokens.

Supervised finetuning (SFT): Pretrained model is further trained on the labeled dataset of input-output pairs.

Reinforcement Learning: Finetune model to generate responses that maximize human preference. This requires the data format (instruction, winning response, losing response).

Long-context finetuning: This modifies the model’s architecture such adjusting the positional embeddings.

Distillation: Finetune a small model to imitate the behavior of a larger model using data generated by the larger model.

When to use:

  • SFT: When model needs to adopt specific behavior, format or style consistently.
  • RAG: When model lack knowledge
  • Prompt: Cheaper first step

Choosing RAG or prompt is whether the model’s failures are information-based or behavior-based.

Memory calculation for training

Model inference: N x M where N=no. of parameters, M is the memory needed for each parameter