
Abstract: Most production information retrieval systems are built on top of Lucene which use tf-idf and BM25.
Current state of the art techniques utilize embeddings for retrieval. This workshop aims to demystify what is involved in building such a system.
This tutorial is broken into four sections :
1) Intro
- Search retrieval concepts: approaches, evaluation metrics etc.
- Overview of common production retrieval stack
- Environment Setup (10 mins)
- Walk over the notebooks and environment setup
2) Non deep learning based retrieval
- Overview of tf-idf and BM-25
- How production systems use ElasticSearch / SOLR
- Hands-on lab experience:
-- Indexing some documents with PySolr
-- Reviewing Retrieval Results from tf-idf
3) Embeddings and Vector Similarity Overview (60 min)
- Brief review of common embedding techniques: word2vec, BERT
- Briefly talk about how to train own custom embeddings
- Vector Similarity and Evaluation metrics
- Hands-on lab experience:
-- Use a pre-trained BERT embedding from HuggingFace transformers library
-- Compare results of Non deep learning and Vector Similarity
4) Serving Vector Similarity using Approximate Nearest Neighbors
- Why Vector Similarity needs ANN
- Review common Approximate Nearest Neighbors techniques in FAISS
- Overview of managed services: VertexAI, Pinecone, Milvus
- Hands-on lab experience:
-- Building FAISS Index
-- Load Index into Milvus
-- Compare Recall vs latency tradeoff
By the end of the session, a user will be able to build a production information retrieval system leveraging Embeddings and Vector Similarity using ANN.
This will allow users to utilize state of the art technologies / techniques on top of the traditional information retrieval systems.
Bio: Nidhin is an Machine Learning Engineer at Walmart where he works on Walmart's E-commerce Search Engine. Before Walmart, he worked for two startups.

Nidhin Pattaniyil
Title
Machine Learning Engineer | Walmart Global Tech
