π Retrieval augmented generation is a method used to improve the accuracy of language models like GPT and Pal.
β The relevance of the training data to the question determines the accuracy of the language model's answer.
π‘ To overcome token limitations in the context, all documents are utilized and additional information is provided when asking questions.
π Using LLM models, we can create embeddings for a book divided into small chunks.
π We use the embedding vectors to retrieve similar documents as context for asking questions to the LLM model.
π‘ By overcoming the challenge of context length, we are able to extract accurate answers.
π LLMs consist of a retriever and a generator.
β Evaluation of LLMs involves assessing both the retriever and the generator.
π Performance evaluation is done based on the retrieved context and the generated answer.
π Context precision measures how relevant the retrieved context is to the question.
π Context recall measures how good the retrieved context is.
βοΈ The value of context precision ranges between 0 and 1, with higher values indicating better relevance.
π Computing context precision and context recall to evaluate the retriever model's ability to extract relevant information.
π Context recall measures the ability to predict important cases correctly based on the ground truth and retrieved context.
β‘ The generator takes question and context as input to provide an answer.
π Faithfulness is the accuracy of the generated answer and is evaluated by comparing it with the retrieved context.
π Answer relevancy measures how relevant the generated answer is to the given question.
π Four metrics are used to evaluate LLMs: faithfulness, answer relevancy, precision, and recall.
π The video discusses the evaluation of LLM models, specifically addressing harmfulness and coherence of answers.
π» The evaluation takes only the answer as input and checks for harmful or malicious content, providing a boolean output.
π In the next video, a Python library called RAGAS will be used to compute these evaluation metrics.