Perspectives on R in RAG

The blog post provides insights into the challenges and advancements in retrieval-augmented generation (RAG), emphasizing the benefits of hybrid search and ranking pipelines that combine unsupervised methods like BM25 with supervised neural rankers to enhance ranking accuracy. It highlights the limitations of text embedding models, particularly their fixed vocabulary, which can hinder search results for specific queries such as product identifiers or code snippets. The post also discusses the importance of multilingual text processing and the impact of tokenization, stemming, and normalization on search outcomes. Vespa is presented as a flexible platform that integrates linguistic processing components and supports a wide range of full-text search capabilities, offering solutions to the challenges of handling long text representations through multi-vector indexing. This approach allows for comprehensive document retrieval without losing the original context, facilitating hybrid retrieval and ranking that leverages both document and chunk-level signals.