Semantic Search Engine

Semantic Search Engine for News Articles Using Sentence Embeddings
Client
Self Development
YeAr
2025
Category
Natural Language Processing (NLP)
Service
Automation & Efficiency Gains
Semantic Search Engine
Tools / Languages Used
  • Python
    • sentence-transformers (for embeddings)
    • FAISS or Chroma (for efficient similarity search)
    • pandas, numpy (data handling)
    • streamlit or gradio (for interactive demo)
  • Optional: Hugging Face Datasets API for loading text corpora
Technical Skills
  • Text embedding generation using pretrained transformer models (Sentence-BERT)
  • Vector similarity search (cosine similarity, FAISS index)
  • Data preprocessing and normalization
  • Building scalable text retrieval systems
  • Model evaluation through relevance ranking metrics (precision@k, recall@k)
  • Deployment of interactive NLP applications
Soft Skills
  • Problem framing: Defined “relevance” and designed evaluation to measure it.
  • Systems thinking: Architected a modular retrieval system separating embedding, storage, and query layers.
  • Communication: Simplified complex NLP concepts (embeddings, vector similarity) for non-technical audiences.
  • User experience: Designed a clean, intuitive search interface for demonstrations.
Step 1: Exploratory Data ANalysis
  • Collected ~10,000+ news articles from a public dataset (e.g., AG News or BBC News).
  • Inspected categories, word counts, and content diversity.
  • Cleaned and normalized text (removed HTML, punctuation, and stopwords).
  • Sample insights:
    • Articles from “Technology” and “Business” often overlapped semantically (shared topics like startups, AI, innovation).
    • Keyword-based search struggled with contextual matches (e.g., “AI chip” vs “semiconductor company”).
Step 2: Solution Design
  • Used Sentence-BERT (all-MiniLM-L6-v2) to create 384-dimensional sentence embeddings for each article.
  • Stored embeddings in a FAISS index for efficient nearest-neighbor search.
  • For a user query:
    • Encode the query into an embedding.
    • Compute cosine similarity with all article vectors.
    • Return the top-k most semantically similar results.
  • Compared performance with simple TF-IDF cosine similarity to show the power of embeddings.
Step 3: Model Assessment
  • Defined evaluation metric: Precision@k — proportion of retrieved articles that share the correct category with the query.
  • Compared:
  • TF-IDF similarity: 0.58 precision@5
  • Sentence-BERT similarity: 0.82 precision@5
  • Qualitative analysis showed the embedding model retrieved conceptually relevant articles even with different phrasing (e.g., query “spacecraft launch” matched “NASA delays rocket mission”).
Step 4: Results / How It’s Used

Built the model for self development. No further deployments associated.

Built the model for self development. No further deployments associated.