According to an embodiment, a candidate node having a potential association relationship with a target node, an association node having an association relationship with the target node, and a grouping identifier of the association node are obtained. A relevance degree between the association node and the target node and a relevance degree between the candidate node and the target node within each grouping identifier are obtained. Based on the relevance degrees, the association node and the candidate node in each grouping identifier are combined for outputting.