GRAPH-BASED RECOMMENDATIONS SERVICE SYSTEMS AND METHODS

A recommendation engine may provide recommendations by obtaining a compact graph representation representing a recommendations graph comprising of nodes and weighted edges. Each node is associated with type metadata indicating that it represents a recommendable item or a non-recommendable item. Each weighted edge is associated with edge-weight metadata. The compact graph representation can be stored in primary memory. When servicing a request for an item recommendation, the recommendation engine selects an entry node based at least in part on context metadata associated with the request, and traverses only a highly-weighted portion of the compact graph representation that is proximate to an entry node to select paths leading respectively to potential recommendation nodes. Each path is scored based on the edge-weight metadata of all segments, and at least one recommendation node is selected based at least in part on the path scores.