Evaluating the relevance of retrieved information for LLMs
While the retrieval metrics discussed in the previous section provide a general assessment of retrieval quality, they do not fully capture the nuances of relevance in the context of RAG. In RAG, the retrieved information is not the end product but rather an intermediate step that serves as input to an LLM. Therefore, we need to evaluate the relevance of the retrieved information not just to the query but also to the specific task of generating a high-quality response via the LLM.
Traditional information retrieval often focuses on finding documents that are topically relevant to the query. However, in RAG, we need a more nuanced notion of relevance that considers the following aspects:
- Answerability: Does the retrieved information contain the specific information needed to answer the query accurately? A document might be generally relevant to the query but not contain the precise answer.
- Contextual utility: Is...