arXiv AI

FedV-KGQA in Practice: Design Lessons and an Interactive Prototype

FedV-KGQA addresses multi‑hop question answering over vertically partitioned knowledge graphs where each silo holds disjoint relation types. The system trains local embeddings, concatenates silo‑specific entity views, anchors questions at a topic entity, and ranks candidates without sharing raw triples. Experiments show federated fusion nearly matches centralized accuracy, that anchoring and enrichment are more critical than embedding choice, and that the cheapest encoder depends on target accuracy.

arXiv AI
Aug 26

FedV-KGQA: Multi-Hop Question Answering over Vertically Partitioned Knowledge Graphs

FedV-KGQA is a framework for multi-hop question answering over knowledge graphs that are vertically partitioned across different organizations. It allows entities to be shared while each silo retains disjoint sets of relations, using local graph enrichment and knowledge graph embeddings so that raw triples and relation parameters never leave the silo. The system includes a topic entity anchoring mechanism to ground questions in the correct graph neighborhood without runtime inter-silo communication, and it achieves performance close to centralized systems on three benchmarks, including 3-hop reasoning and robustness to embedding perturbations.

By Md Saikat Islam Khan Bappy, Oshani Seneviratne
arXiv AI
Aug 11

KGCache: Amortized Subgraph Retrieval for KG Reasoning with LLMs

arXiv:2608. 07954v1 Announce Type: new Abstract: Large language models can answer knowledge-intensive questions more reliably when they are grounded with knowledge graphs, but systems such as Think-on-Graph and Reasoning-on-Graph repeatedly query the same graph neighborhoods across different questions.

By Uros Stanic, Changcheng Yuan, Sabuj Laskar, Ariful Azad
arXiv AI
Sep 2

KGFR: A Foundation Retriever for Generalized Knowledge Graph Question Answering

KGFR introduces a Knowledge Graph Foundation Retriever that collaborates with large language models to enhance knowledge‑intensive question answering. By encoding relations with LLM‑generated descriptions and initializing entities from question roles, KGFR enables zero‑shot generalization to unseen knowledge graphs. Its Asymmetric Progressive Propagation technique efficiently handles large graphs, while a controllable reasoning loop allows the LLM to request candidate answers, supporting facts, and reasoning paths.

By Yuanning Cui, Zequn Sun, Wei Hu, Zhangjie Fu
arXiv Computation and Language
Aug 27

Query-Side Attacks on GNN-Based KGQA: Tracing Failures from Entity Linking to Answer Generation

The paper investigates where failures occur in GNN‑based Knowledge Graph Question Answering pipelines when faced with adversarial question perturbations. By isolating stages—entity linking, subgraph retrieval, GNN reasoning, and answer generation—and applying two answer‑preserving attacks (Compositional Restructuring and Relation Synonym Swap), the authors find that subgraph construction is responsible for over 99% of end‑to‑end failures, even though the correct answer is often present in the retrieved subgraph. This challenges the assumption that reasoning models are the weak link and highlights subgraph construction as the critical mitigation target.

By Pankaj Kumar, Subhankar Mishra
arXiv Machine Learning
Aug 27

A Storage-Retrieval Gap in Parametric Knowledge Graph Memory

The paper investigates a parametric approach to knowledge graph memory by compiling each entity into a LoRA adapter, enabling zero‑cost query-time retrieval via weight injection. On the MetaQA dataset, these adapters encode context‑free factual knowledge, improving exact‑match scores by up to +0.243 over a base model and achieving an oracle gap of +0.283. However, the stored knowledge is not recoverable through similarity or embedding‑based methods, indicating that knowledge is stored locally and does not transfer across semantically neighboring entities.

By Martino M. L. Pulici, Cuong Xuan Chu, Evgeny Kharlamov, Volker Tresp
arXiv Computation and Language
Aug 31

Entity-Memory Graph Retrieval Improves Evidence Coverage in Long-Conversation Question Answering

Entity-Memory graph retrieval preserves dialogue turns as verbatim memory nodes, links repeated mentions via shared entities, and connects adjacent memories with chronological edges. During retrieval, the system gates through entities, fuses semantics, and performs one‑hop chronological recovery before dense backfill, allowing it to keep neighboring memories that dense cosine ranking might miss. On 1,986 questions from ten LoCoMo conversations, this graph retrieval method increases official evidence recall at top‑k 25 from 79.7468 % to 84.4842 %, with the advantage extending from top‑k 5 to 50, though it does not improve overall final‑answer F1.

By Shumao Sun
arXiv Machine Learning
Sep 11

Enabling Knowledge Graph Understanding at Scale with the EXplore Your Graphs ENgine (EXYGEN)

The paper introduces EXYGEN, a framework that enables conversational access to large knowledge graphs by combining VoID descriptions, ShEx schemas, retrieved triples, and example question‑query pairs in a retrieval‑augmented generation pipeline. On the SciQA benchmark, this approach achieves an exact‑match score of 0.419 without fine‑tuning any large language model, and shows that larger general‑purpose LLMs can outperform smaller code‑specialized ones when provided sufficient context. To scale metadata generation for very large KGs, the authors propose a predicate‑coverage‑aware parallel graph sampling strategy that preserves structural diversity, reduces runtime by over 80× on OpenCitations Meta and GESIS, and is the only tractable method for obtaining complete metadata on ORKG.

By Harshdeep Singh, Yurui Zhu, Giovanni Colavizza, Matteo Romanello