Navigating the World of Knowledge Graphs : Part 1

Ashish Patel
ML Research Lab
Published in
8 min readNov 20, 2023

Knowledge Graph with LLM Story

Hey there, fellow knowledge enthusiasts! I’m Ashish Patel, and today, we’re diving headfirst into the fascinating realm of Knowledge Graphs. If you’ve ever wondered how information is intricately connected in the digital world, you’re in for a treat.

Defining Knowledge Graphs: Unraveling the Web of Knowledge

So, what exactly are Knowledge Graphs? Imagine a dynamic, interconnected web of information where entities (think people, places, and things) are linked by relationships. It’s like the ultimate mind map for data, providing context and depth to our understanding.

Embarking on the journey of understanding Knowledge Graphs requires a grasp of the fundamental terminology that forms the building blocks of this intricate system. In this exploration, we’ll unravel key concepts using examples and visualize them with Mermaid code to make the learning experience more tangible.

1. Nodes and Entities: The Foundations of Knowledge

At the heart of a Knowledge Graph are nodes, representing entities or things. These entities can be anything from people to places, concepts, or objects. Each node holds specific information and attributes.

Example: In a social network graph, nodes could represent users, and each user node may have attributes such as username, age, and location.

2. Edges and Relationships: Connecting the Dots

Edges establish relationships between nodes, defining how entities are connected. These relationships are crucial for imparting meaning and context to the data within the Knowledge Graph.

Example: Connecting users in a social network with a “Friend” relationship.

3. Properties: Describing Node Attributes

Properties are key-value pairs associated with nodes or edges, providing additional details about the entities or relationships.

Example: Adding properties to a “User” node.

4. Ontology: Designing the Blueprint

The ontology is the structured framework defining the types of entities, relationships, and properties within a Knowledge Graph. It serves as the blueprint guiding the creation and organization of knowledge.

Example: Designing an ontology for a music-related Knowledge Graph with entities like “Artist,” “Album,” and relationships like “Performed by.”

5. Triplets: Structuring Information

A triplet, or triple, is the basic unit of information in a Knowledge Graph. It consists of a subject, predicate, and object, forming a statement about the data.

Example: The triplet “John likes Music” where “John” is the subject, “likes” is the predicate, and “Music” is the object.

6. Querying: Extracting Insights

Querying involves asking questions or making requests to extract specific information from the Knowledge Graph. It’s the process of navigating the interconnected web of data.

Example: Querying to find friends of John in a social network.

7. Inference: Deriving New Knowledge

Inference involves deducing implicit information from explicit data within the Knowledge Graph. It’s about uncovering connections and knowledge that may not be directly stated.

Example: Inferring that if John is friends with Jane and Jane is friends with Alex, then John might indirectly know Alex.

Understanding these foundational concepts is essential for navigating the world of Knowledge Graphs.

The Engine of Context: Significance in the Era of Big Data

In an era inundated with data, Knowledge Graphs emerge as powerful tools for contextualizing information. They act as the backbone for various applications, enabling us to move beyond isolated data points and understand the intricate connections that define our digital landscape.

Illustrating with a business scenario: Think of an e-commerce platform. Traditional databases may store product information, user data, and purchase history separately. Enter the Knowledge Graph, weaving these elements into a comprehensive tapestry. Suddenly, recommendations become personalized, drawing from the rich tapestry of a user’s preferences, past purchases, and even the collective choices of similar users.

Building the Labyrinth: Constructing a Knowledge Graph Step by Step

Creating a Knowledge Graph involves a meticulous process. It begins with data collection and preprocessing, followed by ontology design — a blueprint defining entities, attributes, and relationships. Linking entities is the next step, forming the intricate web that characterizes a Knowledge Graph.

Follow crash course:

Consider a scenario in a manufacturing setting: Nodes could represent machinery, raw materials, and processes, while edges signify dependencies and manufacturing sequences. This Knowledge Graph not only captures the manufacturing process but also allows for streamlined optimization and predictive maintenance.

Famous Knowledge Graph Projects

1. Never-Ending Language Learning (NELL):

  • Overview: A research project from Carnegie Mellon University, aiming to develop a computer system that continuously learns to read the web, accumulating over 50 million candidate beliefs.
  • Significance: Advances the concept of continual learning, showcasing the dynamic nature of Knowledge Graphs.

2. Freebase / Probase:

  • Overview: A large collaborative knowledge base, deprecated since August 31, 2016. Composed mainly by community members, it provided downloadable data dumps even after its deprecation.
  • Significance: Illustrates the power of community-driven data curation and the challenges of maintaining a vast knowledge repository.

3. Metaweb:

  • Overview: Described as an “open, shared database of the world’s knowledge,” Metaweb developed Freebase, acquired by Google in 2010. Most of its data is now available through Wikidata.
  • Significance: Highlights the collaborative nature of building knowledge databases and the evolution of projects over time.

4. Cyc: Common Sense Knowledge Base:

  • Overview: A repository of common sense knowledge, originating in 1984. Cyc contains vast amounts of fundamental human knowledge, rules of thumb, and heuristics for reasoning about everyday life.
  • Significance: Explores the challenges and possibilities of capturing and organizing human common sense.

5. GDelt:

  • Overview: A platform monitoring global news outlets, identifying people, locations, organizations, and events. It creates an open platform for computing on worldwide data and is supported by Google Jigsaw.
  • Significance: Demonstrates the application of Knowledge Graphs in real-time global event monitoring and analysis.

6. DBpedia:

  • Overview: An open and free knowledge base, continuously improved through a crowd-sourced community effort to extract structured information from Wikipedia.
  • Significance: Showcases the integration of structured data from unstructured sources, emphasizing the power of collaborative knowledge extraction.

7. YAGO:

  • Overview: A semantic knowledge base derived from Wikipedia, WordNet, and GeoNames, developed by the Max-Planck Institute.
  • Significance: Illustrates the creation of a comprehensive semantic network by combining information from diverse sources.

8. Wikidata:

  • Overview: A project by the Wikimedia Foundation, serving as a free, collaborative, multilingual secondary database. It collects structured data to support all Wikimedia projects and beyond.
  • Significance: Emphasizes the importance of structured, multilingual data in supporting a wide range of collaborative projects.

9. LinkedIn’s Knowledge Graph:

  • Overview: Built upon entities on LinkedIn, forming an ontology of the professional world with entities such as members, jobs, titles, skills, companies, and geographical locations.
  • Significance: Highlights the application of Knowledge Graphs in professional networking and the business domain.

10. OpenIE:

  • Overview: A toolkit for quality information extraction at web scale, originating from the University of Washington.
  • Significance: Explores the challenges of extracting meaningful information from unstructured text on a large scale.

11. PROSPERA:

  • Overview: A Hadoop-based scalable knowledge-harvesting engine that combines pattern-based gathering of relational fact candidates.
  • Significance: Showcases the application of big data technologies in harvesting and organizing knowledge.

12. Google Knowledge Vault:

  • Overview: A knowledge base created by Google, contributing to the company’s efforts in understanding and organizing vast amounts of information.
  • Significance: Reflects the role of major tech companies in advancing the field of Knowledge Graphs.

13. ConceptNet:

  • Overview: Originated from the crowdsourcing project Open Mind Common Sense, ConceptNet is a freely-available semantic network.
  • Significance: Illustrates the power of collective intelligence in building a knowledge network.

14. WordNet:

  • Overview: Organizes nouns, verbs, adjectives, and adverbs into synonym sets, representing underlying lexical concepts.
  • Significance: Lays the foundation for semantic relationships between words, contributing to natural language understanding.

Querying Intelligence: Knowledge Graphs and the Role of Large Language Models (LLM)

Knowledge Graphs truly come to life when coupled with Large Language Models (LLMs). These models, powered by artificial intelligence, enhance the querying process, allowing users to interact with the Knowledge Graph using natural language.

Imagine a scenario in a healthcare setting: A doctor could inquire about a patient’s medical history, treatment plans, and relevant research using simple language. LLMs navigate the Knowledge Graph seamlessly, providing actionable insights to inform medical decisions.

Overcoming Challenges: Scalability, Dynamics, and Consistency

As with any sophisticated system, Knowledge Graphs pose challenges. Scaling them to accommodate large datasets, handling dynamic data updates, and maintaining consistency in the face of diverse information sources require strategic solutions.

Visualizing the challenge: Envision a global supply chain network. As suppliers, logistics, and market trends evolve, the Knowledge Graph must adapt in real-time, ensuring accurate and up-to-date insights for effective decision-making.

Future Horizons: Beyond the Horizon of Knowledge Graphs

The journey doesn’t end here. The future holds exciting possibilities for Knowledge Graphs. Emerging technologies like graph neural networks and federated learning are poised to enhance their capabilities, opening new frontiers in data understanding and decision-making.

Peer into the crystal ball: Picture a Knowledge Graph seamlessly integrating data from IoT devices, social networks, and emerging technologies. The result? A holistic understanding of our interconnected world, paving the way for unprecedented advancements.

In Conclusion: Navigating the Complexity

In conclusion, Knowledge Graphs stand as beacons of structured intelligence in our data-driven era. They transform information into knowledge, weaving a complex yet comprehensible tapestry. As we continue to explore this dynamic landscape, the fusion of Knowledge Graphs and Large Language Models heralds a new era of interactive, context-aware data exploration.

Stay curious, stay informed, and join me in the next installment as we venture even deeper into the realms of knowledge representation and artificial intelligence.

Until then, Happy Learning! 🚀✨

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Ashish Patel
ML Research Lab

LLM Expert | Data Scientist | Kaggle Kernel Master | Deep learning Researcher