LLMs: Embeddings and Vector Search

Tarapong Sreenuch
3 min readJul 6, 2023

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Introduction

Recent years have seen an explosion in the development and application of Artificial Intelligence (AI), with Large Language Models (LLMs) such as OpenAI’s GPT-3.5 and Anthropic’s Claude leading the charge in the field of knowledge-based question answering. They have revolutionized the way we process and generate content from data, yet they still face the challenge of context limitations. Tools like embeddings, vector databases, and search technologies offer solutions to these issues, enhancing the LLMs’ functionality and opening the door to a wider range of applications.

Making Sense of Semantics

Embeddings serve as a critical bridge between human language and machine-readable formats in LLMs. These mathematical vectors capture the semantics of a text and can encapsulate a diverse range of unstructured data, from text to images and audio files. This transformation allows for content identification based on semantic similarity rather than literal matching. For instance, in an LLM that provides customer support within a specific industry, training the embeddings on data pertinent to that industry can enhance the model’s precision by acclimating it to the unique terminology and context of that field.

Navigating the Landscape of Knowledge

Vector databases play a fundamental role in LLMs by storing and enabling efficient retrieval of these embeddings. They hold unstructured data as vectors, which allows efficient nearest neighbor searches. The decision to use a vector database, vector library, or a database plugin hinges on several factors.

A vector database, with its ability to store and organize high volumes of data, is typically best for situations where the data changes rapidly. They have the advantage of precomputing and storing embeddings, allowing for quick retrieval during on-demand queries. Vector libraries, however, are generally more suited to static or smaller datasets due to their limited database functionality but provide the advantage of lower overhead and simpler integration.

Database plugins, on the other hand, provide the benefits of a traditional database system like SQL or NoSQL with the added ability to handle vector data. This option allows developers to work within an environment they are already familiar with while still benefiting from the advanced features offered by vector management.

Search and Retrieval

The integration of embeddings and vector databases significantly enhances the search and retrieval process in LLMs, a core component of knowledge-based Q&A systems. The process begins by translating a knowledge base of documents into embedding vectors and storing them in a vector index. User queries are likewise transformed into vectors, which are then compared with the vector index to identify relevant documents.

Two common vector search strategies used are exact search and approximate search. Exact search guarantees a high level of accuracy in identifying the nearest neighbors in the vector space but can be computationally expensive, especially with large datasets. Approximate search, on the other hand, trades a degree of accuracy for speed, making it a faster, more scalable solution for larger databases.

Furthermore, the implementation of filtering strategies within vector databases can greatly optimize the retrieval process. Post-query filtering involves retrieving a larger set of results and then filtering out the irrelevant ones, providing a high level of accuracy at the cost of efficiency. In contrast, in-query filtering incorporates filter conditions during the search, balancing efficiency and accuracy. Pre-query filtering applies the filters before the search, offering high efficiency at the risk of potentially missing relevant results.

Optimizing for Performance and Mitigating

Risks Achieving optimal retrieval performance requires the judicious selection of the embedding model and an appropriate document storage method. Safeguards like explicit instructions in prompts, failover logic, a toxicity classification model, and time-out settings for prolonged queries are instrumental in avoiding potential pitfalls. User feedback and observed behavior are invaluable resources for iterative refinements and system improvements over time.

Conclusion

Embeddings and vector databases are revolutionizing how LLMs interact with data, circumventing inherent limitations and moving us towards an AI future where our unique datasets and proprietary knowledge can be seamlessly utilized. As this field continues to evolve, these foundational technologies provide a roadmap to navigate the challenges ahead and unlock new frontiers in AI. With ongoing research into semantic representations, embedding techniques, and innovative database structures, we can look forward to even more efficient, reliable, and responsive AI systems.

#embeddings #vectordatabase #largelanguagemodel #generativeai #nlp

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