Finding Minimum Connected Subgraphs with Ontology Exploration on Large RDF Data

10/13/2020
by   Xiangnan Ren, et al.
0

In this paper, we study the following problem: given a knowledge graph (KG) and a set of input vertices (representing concepts or entities) and edge labels, we aim to find the smallest connected subgraphs containing all of the inputs. This problem plays a key role in KG-based search engines and natural language question answering systems, and it is a natural extension of the Steiner tree problem, which is known to be NP-hard. We present RECON, a system for finding approximate answers. RECON aims at achieving high accuracy with instantaneous response (i.e., sub-second/millisecond delay) over KGs with hundreds of millions edges without resorting to expensive computational resources. Furthermore, when no answer exists due to disconnection between concepts and entities, RECON refines the input to a semantically similar one based on the ontology, and attempt to find answers with respect to the refined input. We conduct a comprehensive experimental evaluation of RECON. In particular we compare it with five existing approaches for finding approximate Steiner trees. Our experiments on four large real and synthetic KGs show that RECON significantly outperforms its competitors and incurs a much smaller memory footprint.

READ FULL TEXT

page 1

page 2

page 3

page 4

08/19/2019

Message Passing for Complex Question Answering over Knowledge Graphs

Question answering over knowledge graphs (KGQA) has evolved from simple ...
10/29/2018

R-BBG_2: Recursive Bipartition of Bi-connected Graphs

Given an undirected graph G(V, E), it is well known that partitioning a ...
09/07/2018

Top-k Overlapping Densest Subgraphs: Approximation and Complexity

A central problem in graph mining is finding dense subgraphs, with sever...
02/22/2022

Knowledge Base Question Answering by Case-based Reasoning over Subgraphs

Question answering (QA) over real-world knowledge bases (KBs) is challen...
07/19/2018

Exact Algorithms for Finding Well-Connected 2-Clubs in Real-World Graphs: Theory and Experiments

Finding (maximum-cardinality) "cliquish" subgraphs is a central topic in...
02/28/2021

Discovering Dense Correlated Subgraphs in Dynamic Networks

Given a dynamic network, where edges appear and disappear over time, we ...
12/25/2020

Brain-inspired Search Engine Assistant based on Knowledge Graph

Search engines can quickly response a hyperlink list according to query ...