activity
20182026
most citedTweetsCOV19 -- A Knowledge Base of Semantically Annotated Tweets about the COVID-19 Pandemic

81 citations · 225 across the 21 of their papers we have counts for

collaborators

21 papers

cs.CL2026

Can Language Models Analyze Data? Evaluating Large Language Models for Question Answering over Datasets

Andreas Xenofontos, Pavlos Fafalios

This paper investigates the effectiveness of large language models (LLMs) in answering questions over datasets. We examine their performance in two scenarios: (a) directly answerin…

cs.DL2023

FastCat Catalogues: Interactive Entity-based Exploratory Analysis of Archival Documents

Georgios Rinakakis, Kostas Petrakis, Yannis Tzitzikas +1

We describe FastCat Catalogues, a Web application that supports researchers studying archival material, such as historians, in exploring and quantitatively analysing the data (tran…

cs.DB2023★ 7 cited

A Workflow Model for Holistic Data Management and Semantic Interoperability in Quantitative Archival Research

Pavlos Fafalios, Yannis Marketakis, Anastasia Axaridou +2

Archival research is a complicated task that involves several diverse activities for the extraction of evidence and knowledge from a set of archival documents. The involved activit…

cs.DB2023★ 12 cited

The SeaLiT Ontology -- An Extension of CIDOC-CRM for the Modeling and Integration of Maritime History Information

Pavlos Fafalios, Athina Kritsotaki, Martin Doerr

We describe the construction and use of the SeaLiT Ontology, an extension of the ISO standard CIDOC-CRM for the modelling and integration of maritime history information. The ontol…

cs.DB2022

Estimating the Cost of Executing Link Traversal based SPARQL Queries

Antonis Sklavos, Pavlos Fafalios, Yannis Tzitzikas

An increasing number of organisations in almost all fields have started adopting semantic web technologies for publishing their data as open, linked and interoperable (RDF) dataset…

cs.DL2021★ 4 cited

Towards Semantic Interoperability in Historical Research: Documenting Research Data and Knowledge with Synthesis

Pavlos Fafalios, Konstantina Konsolaki, Lida Charami +6

A vast area of research in historical science concerns the documentation and study of artefacts and related evidence. Current practice mostly uses spreadsheets or simple relational…

cs.DL2021★ 15 cited

FAST CAT: Collaborative Data Entry and Curation for Semantic Interoperability in Digital Humanities

Pavlos Fafalios, Kostas Petrakis, Georgios Samaritakis +4

Descriptive and empirical sciences, such as History, are the sciences that collect, observe and describe phenomena in order to explain them and draw interpretative conclusions abou…

cs.CL2021★ 3 cited

Better Together -- An Ensemble Learner for Combining the Results of Ready-made Entity Linking Systems

Renato Stoffalette João, Pavlos Fafalios, Stefan Dietze

Entity linking (EL) is the task of automatically identifying entity mentions in text and resolving them to a corresponding entity in a reference knowledge base like Wikipedia. Thro…

cs.CL2020★ 13 cited

Exploiting stance hierarchies for cost-sensitive stance detection of Web documents

Arjun Roy, Pavlos Fafalios, Asif Ekbal +2

Fact checking is an essential challenge when combating fake news. Identifying documents that agree or disagree with a particular statement (claim) is a core task in this process. I…

cs.SI2020★ 81 cited

TweetsCOV19 -- A Knowledge Base of Semantically Annotated Tweets about the COVID-19 Pandemic

Dimitar Dimitrov, Erdal Baran, Pavlos Fafalios +4

Publicly available social media archives facilitate research in the social sciences and provide corpora for training and testing a wide range of machine learning and natural langua…

cs.CY2020★ 22 cited

Bias in Data-driven AI Systems -- An Introductory Survey

Eirini Ntoutsi, Pavlos Fafalios, Ujwal Gadiraju +20

AI-based systems are widely employed nowadays to make decisions that have far-reaching impacts on individuals and society. Their decisions might affect everyone, everywhere and any…

cs.DB2018★ 4 cited

How Many and What Types of SPARQL Queries can be Answered through Zero-Knowledge Link Traversal?

Pavlos Fafalios, Yannis Tzitzikas

The current de-facto way to query the Web of Data is through the SPARQL protocol, where a client sends queries to a server through a SPARQL endpoint. Contrary to an HTTP server, pr…

cs.CL2018★ 1 cited

Same but Different: Distant Supervision for Predicting and Understanding Entity Linking Difficulty

Renato Stoffalette João, Pavlos Fafalios, Stefan Dietze

Entity Linking (EL) is the task of automatically identifying entity mentions in a piece of text and resolving them to a corresponding entity in a reference knowledge base like Wiki…

cs.SI2018★ 8 cited

Tracking the History and Evolution of Entities: Entity-centric Temporal Analysis of Large Social Media Archives

Pavlos Fafalios, Vasileios Iosifidis, Kostas Stefanidis +1

How did the popularity of the Greek Prime Minister evolve in 2015? How did the predominant sentiment about him vary during that period? Were there any controversial sub-periods? Wh…

cs.DL2018★ 3 cited

Building and Querying Semantic Layers for Web Archives (Extended Version)

Pavlos Fafalios, Helge Holzmann, Vaibhav Kasturia +1

Web archiving is the process of collecting portions of the Web to ensure that the information is preserved for future exploitation. However, despite the increasing number of web ar…

cs.IR2018★ 1 cited

Towards a Ranking Model for Semantic Layers over Digital Archives

Pavlos Fafalios, Vaibhav Kasturia, Wolfgang Nejdl

Archived collections of documents (like newspaper archives) serve as important information sources for historians, journalists, sociologists and other interested parties. Semantic…

cs.IR2018★ 3 cited

Ranking Archived Documents for Structured Queries on Semantic Layers

Pavlos Fafalios, Vaibhav Kasturia, Wolfgang Nejdl

Archived collections of documents (like newspaper and web archives) serve as important information sources in a variety of disciplines, including Digital Humanities, Historical Sci…

cs.SI2018★ 16 cited

Viewpoint Discovery and Understanding in Social Networks

Mainul Quraishi, Pavlos Fafalios, Eelco Herder

The Web has evolved to a dominant platform where everyone has the opportunity to express their opinions, to interact with other users, and to debate on emerging events happening ar…

cs.IR2018★ 29 cited

TweetsKB: A Public and Large-Scale RDF Corpus of Annotated Tweets

Pavlos Fafalios, Vasileios Iosifidis, Eirini Ntoutsi +1

Publicly available social media archives facilitate research in a variety of fields, such as data science, sociology or the digital humanities, where Twitter has emerged as one of…

cs.IR2018★ 3 cited

Time-Aware and Corpus-Specific Entity Relatedness

Nilamadhaba Mohapatra, Vasileios Iosifidis, Asif Ekbal +2

Entity relatedness has emerged as an important feature in a plethora of applications such as information retrieval, entity recommendation and entity linking. Given an entity, for i…

cs.DB2018

Heuristics-based Query Reordering for Federated Queries in SPARQL 1.1 and SPARQL-LD

Thanos Yannakis, Pavlos Fafalios, Yannis Tzitzikas

The federated query extension of SPARQL 1.1 allows executing queries distributed over different SPARQL endpoints. SPARQL-LD is a recent extension of SPARQL 1.1 which enables to dir…