Knowledge graph node expiration

A system for deleting a node of a knowledge graph, said system comprising:

• a computer system comprising:
• a computer processor, a computer-readable storage medium, and program instructions stored on the computer-readable storage medium being executable by the processor;
• a storage medium for storing a knowledge graph data comprising nodes and edges, said edges representing relationships between a subset of said nodes;
• a first determining unit adapted for determining a first relevance degree value for a selected one of said nodes based on a combination of node parameters using a first relevance scoring model;
• a second determining unit adapted determining a second relevance degree value for the selected node based on a combination of node parameters using a second relevance scoring model;
• a combination module adapted for combining said first relevance degree value and said second relevance degree value into a final relevance degree for said selected node;
• a marking unit adapted for marking said selected node as deletable if said final relevance degree value is above a predefined relevance threshold value;
• a query module adapted for applying queries against said knowledge graph, wherein at least a certain number of such queries invokes accessing of a node marked as deletable;
• a revising system adapted for revising at least one of said first relevance degree value and said second relevance degree value based on said accessing of said node marked as deletable;
• and
• a deletion module adapted for deleting said node marked as deletable if over a predetermined period of time queries against said knowledge graph invoke no access of said node marked as deletable.

A computer program product for deleting a node of a knowledge graph, said computer program product comprising a computer readable storage medium having program instructions embodied therewith, said program instructions being executable by one or more computing systems to cause said one or more computing systems to:

• receive knowledge graph data comprising nodes and edges, said edges representing a relationships between a subset of said nodes;
• determine a first relevance degree value for a selected one of said nodes based on a combination of node parameters using a first relevance scoring model;
• determine a second relevance degree value for said selected node based on a combination of node parameters using a second relevance scoring model;
• combine said first relevance degree value and said second relevance degree value into a final relevance degree for said selected node;
• mark said selected node as deletable if said final relevance degree value is above a predefined relevance threshold value;
• apply queries against said knowledge graph, wherein at least a certain number of such queries invokes accessing of a node, marked as deletable;
• revise at least one of said first relevance degree value and said second relevance degree value based on said accessing of said node marked as deletable;
• and
• delete said node, marked as deletable, if over a predetermined period of time queries against said knowledge graph invoke no access of said node, marked as deletable.