Discovering the Power of Lexical Search in RAG Applications

Hosted by John Berryman

192 students

What you'll learn

Semantic vs Lexical

You'll see the places where semantic search is weak. These are the exact places where lexical is strong.

Lexical Search Basics

We'll explain lexical search so that you can understand how it works and why it is ideal for certain domains.

Intro to Elasticsearch

Attendees will get a super fast tour of how to build an end-to-end Elasticsearch-based RAG application.

Why this topic matters

Semantic search has become the defacto standard for retrieval augmented generation (RAG). But in certain situations semantic search is just a bad fit. Lexical search – an older technology – offers a tried-and-true alternative that can be easier to set up, easier to understand and improve. This talk will open your eyes to new possibilities with lexical search.

You'll learn from

John Berryman

AI Consultant @ Arcturus Labs

John Berryman is the founder of Arcturus Labs. His journey through AI and search technologies includes contributing to GitHub Copilot's early development, where he worked on the team that brought AI-assisted coding from concept to reality. Throughout his career, John has helped build search and recommendation systems that millions use daily – from GitHub's code search infrastructure to Eventbrite's discovery platform and the US Patent Office's next-generation search system. This blend of experience in both foundational search technologies and cutting-edge AI applications gives him unique insight into building practical, powerful LLM applications.


John shares his expertise through two books: Relevant Search, which reveals the art and science of building search applications, and Prompt Engineering for LLMs, which guides developers through the emerging practice of language model application development.

Employeers, Publishers

GitHub
GitHub Copilot
Eventbrite
Manning Publications
O'Reilly Media
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