Neo4j, a graph database, has been used for two years and was discovered three years ago while studying statistics with a focus on social networks. It's powerful and easy to use, especially for real-time recommendation engines. The text explains how to incorporate statistical methods into these recommendations using Cypher queries. Three types of recommendations are explored: simple graph-powered recommendations, social recommendations, and similarity recommendations. The first type recommends food places based on location, while the second type recommends places liked by friends of a logged-in user. The third type uses Euclidean distance to find similar users based on their ratings. Finally, a clustering recommendation engine is introduced, which involves using statistical software like R or Python to run an algorithm and then persisting the results in Neo4j for real-time querying. This allows for complex patterns to be expressed in just a few lines of Cypher code.