A foundational model is a pretrained machine-learning model used as a general base for further adaptation or specialization. Fine-tuning trains it with additional data to improve contextual understanding, change its tone, or target specific queries and instructions. section 12.1.1
Fine-tuning develops a foundational model through several connected activities:
- Set a specific goal for the adapted model. section 12.1.1
- Prepare relevant data and format it for training. section 12.3
- Tokenize training prompts while respecting the model’s context length. section 12.3
- Test the tuned model through automated inference or manual evaluation. section 12.3
Model families and products
GPT-3.5-Turbo and GPT-4o are used as foundation models for products including ChatGPT, GitHub Copilot, and Microsoft Bing AI. Gemini provides related model variants, including Gemini 1.5 Pro, Gemini 1.5 Flash, and Gemini 1.0 Pro. section 2.5.2
Figure 12.1 A visual representation of the different steps taken during fine-tuning
Use the process map to follow how goal setting, data preparation, processing, tuning, and testing feed into fine-tuning. section 12.1.1




















