---
_id: '57240'
abstract:
- lang: eng
text: Validating assertions before adding them to a knowledge graph is an essential
part of its creation and maintenance. Due to the sheer size of knowledge graphs,
automatic fact-checking approaches have been developed. These approaches rely
on reference knowledge to decide whether a given assertion is correct. Recent
hybrid approaches achieve good results by including several knowledge sources.
However, it is often impractical to provide a sheer quantity of textual knowledge
or generate embedding models to leverage these hybrid approaches. We present FaVEL,
an approach that uses algorithm selection and ensemble learning to amalgamate
several existing fact-checking approaches that rely solely on a reference knowledge
graph and, hence, use fewer resources than current hybrid approaches. For our
evaluation, we create updated versions of two existing datasets and a new dataset
dubbed FaVEL-DS. Our evaluation compares our approach to 15 fact-checking approaches—including
the state-of-the-art approach HybridFC—on 3 datasets. Our results demonstrate
that FaVEL outperforms all other approaches significantly by at least 0.04 in
terms of the area under the ROC curve. Our source code, datasets, and evaluation
results are open-source and can be found at https://github.com/dice-group/favel.
author:
- first_name: Umair
full_name: Qudus, Umair
id: '83392'
last_name: Qudus
orcid: 0000-0001-6714-8729
- first_name: Michael
full_name: Röder, Michael
id: '67199'
last_name: Röder
orcid: https://orcid.org/0000-0002-8609-8277
- first_name: Franck Lionel
full_name: Tatkeu Pekarou, Franck Lionel
last_name: Tatkeu Pekarou
- first_name: Ana Alexandra
full_name: Morim da Silva, Ana Alexandra
id: '72108'
last_name: Morim da Silva
- first_name: Axel-Cyrille
full_name: Ngonga Ngomo, Axel-Cyrille
id: '65716'
last_name: Ngonga Ngomo
citation:
ama: 'Qudus U, Röder M, Tatkeu Pekarou FL, Morim da Silva AA, Ngonga Ngomo A-C.
FaVEL: Fact Validation Ensemble Learning. In: Rospocher M, Mehwish Alam, eds.
EKAW 2024. ; 2024.'
apa: 'Qudus, U., Röder, M., Tatkeu Pekarou, F. L., Morim da Silva, A. A., &
Ngonga Ngomo, A.-C. (2024). FaVEL: Fact Validation Ensemble Learning. In M. Rospocher
& Mehwish Alam (Eds.), EKAW 2024.'
bibtex: '@inproceedings{Qudus_Röder_Tatkeu Pekarou_Morim da Silva_Ngonga Ngomo_2024,
title={FaVEL: Fact Validation Ensemble Learning}, booktitle={EKAW 2024}, author={Qudus,
Umair and Röder, Michael and Tatkeu Pekarou, Franck Lionel and Morim da Silva,
Ana Alexandra and Ngonga Ngomo, Axel-Cyrille}, editor={Rospocher, Marco and Mehwish
Alam}, year={2024} }'
chicago: 'Qudus, Umair, Michael Röder, Franck Lionel Tatkeu Pekarou, Ana Alexandra
Morim da Silva, and Axel-Cyrille Ngonga Ngomo. “FaVEL: Fact Validation Ensemble
Learning.” In EKAW 2024, edited by Marco Rospocher and Mehwish Alam, 2024.'
ieee: 'U. Qudus, M. Röder, F. L. Tatkeu Pekarou, A. A. Morim da Silva, and A.-C.
Ngonga Ngomo, “FaVEL: Fact Validation Ensemble Learning,” in EKAW 2024,
Amsterdam, Netherlands, 2024.'
mla: 'Qudus, Umair, et al. “FaVEL: Fact Validation Ensemble Learning.” EKAW 2024,
edited by Marco Rospocher and Mehwish Alam, 2024.'
short: 'U. Qudus, M. Röder, F.L. Tatkeu Pekarou, A.A. Morim da Silva, A.-C. Ngonga
Ngomo, in: M. Rospocher, Mehwish Alam (Eds.), EKAW 2024, 2024.'
conference:
end_date: 2024-11-28
location: Amsterdam, Netherlands
name: 24th International Conference on Knowledge Engineering and Knowledge Management
start_date: 2024-11-26
corporate_editor:
- Mehwish Alam
date_created: 2024-11-19T14:12:49Z
date_updated: 2025-09-11T09:48:12Z
ddc:
- '600'
department:
- _id: '34'
editor:
- first_name: Marco
full_name: Rospocher, Marco
last_name: Rospocher
file:
- access_level: closed
content_type: application/pdf
creator: uqudus
date_created: 2024-11-19T14:14:14Z
date_updated: 2024-11-19T14:14:14Z
file_id: '57241'
file_name: favel.pdf
file_size: 190661
relation: main_file
success: 1
file_date_updated: 2024-11-19T14:14:14Z
has_accepted_license: '1'
keyword:
- fact checking
- ensemble learning
- transfer learning
- knowledge management.
language:
- iso: eng
popular_science: '1'
project:
- _id: '412'
name: 'NEBULA: Nutzerzentrierte KI-basierte Erkennung von Fake-News und Fehlinformationen'
- _id: '285'
name: 'SAIL: SAIL - Nachhaltiger Lebenszyklus von intelligenten soziotechnischen
Systemen'
- _id: '410'
name: 'KnowGraphs: KnowGraphs: Knowledge Graphs at Scale'
publication: EKAW 2024
quality_controlled: '1'
status: public
title: 'FaVEL: Fact Validation Ensemble Learning'
type: conference
user_id: '83392'
year: '2024'
...
---
_id: '50479'
abstract:
- lang: eng
text: Verifying assertions is an essential part of creating and maintaining knowledge
graphs. Most often, this task cannot be carried out manually due to the sheer
size of modern knowledge graphs. Hence, automatic fact-checking approaches have
been proposed over the last decade. These approaches aim to compute automatically
whether a given assertion is correct or incorrect. However, most fact-checking
approaches are binary classifiers that fail to consider the volatility of some
assertions, i.e., the fact that such assertions are only valid at certain times
or for specific time intervals. Moreover, the few approaches able to predict when
an assertion was valid (i.e., time-point prediction approaches) rely on manual
feature engineering. This paper presents TEMPORALFC, a temporal fact-checking
approach that uses multiple sources of background knowledge to assess the veracity
and temporal validity of a given assertion. We evaluate TEMPORALFC on two datasets
and compare it to the state of the art in fact-checking and time-point prediction.
Our results suggest that TEMPORALFC outperforms the state of the art on the fact-checking
task by 0.13 to 0.15 in terms of Area Under the Receiver Operating Characteristic
curve and on the time-point prediction task by 0.25 to 0.27 in terms of Mean Reciprocal
Rank. Our code is open-source and can be found at https://github.com/dice-group/TemporalFC.
author:
- first_name: Umair
full_name: Qudus, Umair
last_name: Qudus
- first_name: Michael
full_name: Röder, Michael
last_name: Röder
- first_name: Sabrina
full_name: Kirrane, Sabrina
last_name: Kirrane
- first_name: Axel-Cyrille Ngonga
full_name: Ngomo, Axel-Cyrille Ngonga
last_name: Ngomo
citation:
ama: 'Qudus U, Röder M, Kirrane S, Ngomo A-CN. TemporalFC: A Temporal Fact Checking
Approach over Knowledge Graphs. In: R. Payne T, Presutti V, Qi G, et al., eds.
The Semantic Web – ISWC 2023. Vol 14265. Lecture Notes in Computer Science.
Springer, Cham; 2023:465–483. doi:10.1007/978-3-031-47240-4_25'
apa: 'Qudus, U., Röder, M., Kirrane, S., & Ngomo, A.-C. N. (2023). TemporalFC:
A Temporal Fact Checking Approach over Knowledge Graphs. In T. R. Payne, V. Presutti,
G. Qi, M. Poveda-Villalón, G. Stoilos, L. Hollink, Z. Kaoudi, G. Cheng, &
J. Li (Eds.), The Semantic Web – ISWC 2023 (Vol. 14265, pp. 465–483). Springer,
Cham. https://doi.org/10.1007/978-3-031-47240-4_25'
bibtex: '@inproceedings{Qudus_Röder_Kirrane_Ngomo_2023, place={Cham}, series={ Lecture
Notes in Computer Science}, title={TemporalFC: A Temporal Fact Checking Approach
over Knowledge Graphs}, volume={14265}, DOI={10.1007/978-3-031-47240-4_25},
booktitle={The Semantic Web – ISWC 2023}, publisher={Springer, Cham}, author={Qudus,
Umair and Röder, Michael and Kirrane, Sabrina and Ngomo, Axel-Cyrille Ngonga},
editor={R. Payne, Terry and Presutti, Valentina and Qi, Guilin and Poveda-Villalón,
María and Stoilos, Giorgos and Hollink, Laura and Kaoudi, Zoi and Cheng, Gong
and Li, Juanzi}, year={2023}, pages={465–483}, collection={ Lecture Notes in Computer
Science} }'
chicago: 'Qudus, Umair, Michael Röder, Sabrina Kirrane, and Axel-Cyrille Ngonga
Ngomo. “TemporalFC: A Temporal Fact Checking Approach over Knowledge Graphs.”
In The Semantic Web – ISWC 2023, edited by Terry R. Payne, Valentina Presutti,
Guilin Qi, María Poveda-Villalón, Giorgos Stoilos, Laura Hollink, Zoi Kaoudi,
Gong Cheng, and Juanzi Li, 14265:465–483. Lecture Notes in Computer Science.
Cham: Springer, Cham, 2023. https://doi.org/10.1007/978-3-031-47240-4_25.'
ieee: 'U. Qudus, M. Röder, S. Kirrane, and A.-C. N. Ngomo, “TemporalFC: A Temporal
Fact Checking Approach over Knowledge Graphs,” in The Semantic Web – ISWC 2023,
Athens, Greece, 2023, vol. 14265, pp. 465–483, doi: 10.1007/978-3-031-47240-4_25.'
mla: 'Qudus, Umair, et al. “TemporalFC: A Temporal Fact Checking Approach over Knowledge
Graphs.” The Semantic Web – ISWC 2023, edited by Terry R. Payne et al.,
vol. 14265, Springer, Cham, 2023, pp. 465–483, doi:10.1007/978-3-031-47240-4_25.'
short: 'U. Qudus, M. Röder, S. Kirrane, A.-C.N. Ngomo, in: T. R. Payne, V. Presutti,
G. Qi, M. Poveda-Villalón, G. Stoilos, L. Hollink, Z. Kaoudi, G. Cheng, J. Li
(Eds.), The Semantic Web – ISWC 2023, Springer, Cham, Cham, 2023, pp. 465–483.'
conference:
end_date: 2023-11-10
location: Athens, Greece
name: The Semantic Web – ISWC 2023
start_date: 2023-11-06
date_created: 2024-01-13T11:22:15Z
date_updated: 2024-01-13T11:48:28Z
ddc:
- '006'
department:
- _id: '34'
doi: 10.1007/978-3-031-47240-4_25
editor:
- first_name: Terry
full_name: R. Payne, Terry
last_name: R. Payne
- first_name: Valentina
full_name: Presutti, Valentina
last_name: Presutti
- first_name: Guilin
full_name: Qi, Guilin
last_name: Qi
- first_name: María
full_name: Poveda-Villalón, María
last_name: Poveda-Villalón
- first_name: Giorgos
full_name: Stoilos, Giorgos
last_name: Stoilos
- first_name: Laura
full_name: Hollink, Laura
last_name: Hollink
- first_name: Zoi
full_name: Kaoudi, Zoi
last_name: Kaoudi
- first_name: Gong
full_name: Cheng, Gong
last_name: Cheng
- first_name: Juanzi
full_name: Li, Juanzi
last_name: Li
file:
- access_level: closed
content_type: application/pdf
creator: uqudus
date_created: 2024-01-13T11:25:48Z
date_updated: 2024-01-13T11:25:48Z
file_id: '50480'
file_name: ISWC 2023 TemporalFC-A Temporal Fact Checking approach over Knowledge
Graphs.pdf
file_size: 1944818
relation: main_file
success: 1
file_date_updated: 2024-01-13T11:25:48Z
has_accepted_license: '1'
intvolume: ' 14265'
jel:
- C
keyword:
- temporal fact checking · ensemble learning · transfer learning · time-point prediction
· temporal knowledge graphs
language:
- iso: eng
page: 465–483
place: Cham
project:
- _id: '410'
grant_number: '860801'
name: 'KnowGraphs: KnowGraphs: Knowledge Graphs at Scale'
publication: The Semantic Web – ISWC 2023
publication_identifier:
isbn:
- '9783031472398'
- '9783031472404'
issn:
- 0302-9743
- 1611-3349
publication_status: published
publisher: Springer, Cham
series_title: ' Lecture Notes in Computer Science'
status: public
title: 'TemporalFC: A Temporal Fact Checking Approach over Knowledge Graphs'
type: conference
user_id: '83392'
volume: 14265
year: '2023'
...
---
_id: '46248'
author:
- first_name: Caglar
full_name: Demir, Caglar
id: '43817'
last_name: Demir
- first_name: Michel
full_name: Wiebesiek, Michel
last_name: Wiebesiek
- first_name: Renzhong
full_name: Lu, Renzhong
last_name: Lu
- first_name: Axel-Cyrille
full_name: Ngonga Ngomo, Axel-Cyrille
id: '65716'
last_name: Ngonga Ngomo
- first_name: Stefan
full_name: Heindorf, Stefan
id: '11871'
last_name: Heindorf
orcid: 0000-0002-4525-6865
citation:
ama: 'Demir C, Wiebesiek M, Lu R, Ngonga Ngomo A-C, Heindorf S. LitCQD: Multi-Hop
Reasoning in Incomplete Knowledge Graphs with Numeric Literals. ECML PKDD.
Published online 2023.'
apa: 'Demir, C., Wiebesiek, M., Lu, R., Ngonga Ngomo, A.-C., & Heindorf, S.
(2023). LitCQD: Multi-Hop Reasoning in Incomplete Knowledge Graphs with Numeric
Literals. ECML PKDD. European Conference on Machine Learning and Principles
and Practice of Knowledge Discovery in Databases, Torino.'
bibtex: '@article{Demir_Wiebesiek_Lu_Ngonga Ngomo_Heindorf_2023, title={LitCQD:
Multi-Hop Reasoning in Incomplete Knowledge Graphs with Numeric Literals}, journal={ECML
PKDD}, author={Demir, Caglar and Wiebesiek, Michel and Lu, Renzhong and Ngonga
Ngomo, Axel-Cyrille and Heindorf, Stefan}, year={2023} }'
chicago: 'Demir, Caglar, Michel Wiebesiek, Renzhong Lu, Axel-Cyrille Ngonga Ngomo,
and Stefan Heindorf. “LitCQD: Multi-Hop Reasoning in Incomplete Knowledge Graphs
with Numeric Literals.” ECML PKDD, 2023.'
ieee: 'C. Demir, M. Wiebesiek, R. Lu, A.-C. Ngonga Ngomo, and S. Heindorf, “LitCQD:
Multi-Hop Reasoning in Incomplete Knowledge Graphs with Numeric Literals,” ECML
PKDD, 2023.'
mla: 'Demir, Caglar, et al. “LitCQD: Multi-Hop Reasoning in Incomplete Knowledge
Graphs with Numeric Literals.” ECML PKDD, 2023.'
short: C. Demir, M. Wiebesiek, R. Lu, A.-C. Ngonga Ngomo, S. Heindorf, ECML PKDD
(2023).
conference:
location: Torino
name: European Conference on Machine Learning and Principles and Practice of Knowledge
Discovery in Databases
date_created: 2023-08-01T09:24:21Z
date_updated: 2024-03-06T16:18:53Z
ddc:
- '000'
department:
- _id: '574'
- _id: '760'
file:
- access_level: open_access
content_type: application/pdf
creator: cdemir
date_created: 2023-08-01T09:24:15Z
date_updated: 2023-08-01T09:24:15Z
file_id: '46249'
file_name: public.pdf
file_size: 562759
relation: main_file
file_date_updated: 2023-08-01T09:24:15Z
has_accepted_license: '1'
language:
- iso: eng
oa: '1'
project:
- _id: '407'
grant_number: '101070305'
name: 'ENEXA: Efficient Explainable Learning on Knowledge Graphs'
- _id: '410'
grant_number: '860801'
name: 'KnowGraphs: KnowGraphs: Knowledge Graphs at Scale'
- _id: '285'
grant_number: NW21-059D
name: 'SAIL: SAIL: SustAInable Life-cycle of Intelligent Socio-Technical Systems'
publication: ECML PKDD
status: public
title: 'LitCQD: Multi-Hop Reasoning in Incomplete Knowledge Graphs with Numeric Literals'
type: journal_article
user_id: '14931'
year: '2023'
...
---
_id: '33734'
abstract:
- lang: eng
text: 'Many applications require explainable node classification in knowledge graphs.
Towards this end, a popular ``white-box'''' approach is class expression learning:
Given sets of positive and negative nodes, class expressions in description logics
are learned that separate positive from negative nodes. Most existing approaches
are search-based approaches generating many candidate class expressions and selecting
the best one. However, they often take a long time to find suitable class expressions.
In this paper, we cast class expression learning as a translation problem and
propose a new family of class expression learning approaches which we dub neural
class expression synthesizers. Training examples are ``translated'''' into class
expressions in a fashion akin to machine translation. Consequently, our synthesizers
are not subject to the runtime limitations of search-based approaches. We study
three instances of this novel family of approaches based on LSTMs, GRUs, and set
transformers, respectively. An evaluation of our approach on four benchmark datasets
suggests that it can effectively synthesize high-quality class expressions with
respect to the input examples in approximately one second on average. Moreover,
a comparison to state-of-the-art approaches suggests that we achieve better F-measures
on large datasets. For reproducibility purposes, we provide our implementation
as well as pretrained models in our public GitHub repository at https://github.com/dice-group/NeuralClassExpressionSynthesis'
author:
- first_name: N'Dah Jean
full_name: KOUAGOU, N'Dah Jean
id: '87189'
last_name: KOUAGOU
- first_name: Stefan
full_name: Heindorf, Stefan
id: '11871'
last_name: Heindorf
orcid: 0000-0002-4525-6865
- first_name: Caglar
full_name: Demir, Caglar
id: '43817'
last_name: Demir
- first_name: Axel-Cyrille
full_name: Ngonga Ngomo, Axel-Cyrille
id: '65716'
last_name: Ngonga Ngomo
citation:
ama: 'KOUAGOU NJ, Heindorf S, Demir C, Ngonga Ngomo A-C. Neural Class Expression
Synthesis. In: Pesquita C, Jimenez-Ruiz E, McCusker J, et al., eds. The Semantic
Web - 20th Extended Semantic Web Conference (ESWC 2023). Vol 13870. Springer
International Publishing; 2023:209-226. doi:https://doi.org/10.1007/978-3-031-33455-9_13'
apa: KOUAGOU, N. J., Heindorf, S., Demir, C., & Ngonga Ngomo, A.-C. (2023).
Neural Class Expression Synthesis. In C. Pesquita, E. Jimenez-Ruiz, J. McCusker,
D. Faria, M. Dragoni, A. Dimou, R. Troncy, & S. Hertling (Eds.), The Semantic
Web - 20th Extended Semantic Web Conference (ESWC 2023) (Vol. 13870, pp. 209–226).
Springer International Publishing. https://doi.org/10.1007/978-3-031-33455-9_13
bibtex: '@inproceedings{KOUAGOU_Heindorf_Demir_Ngonga Ngomo_2023, title={Neural
Class Expression Synthesis}, volume={13870}, DOI={https://doi.org/10.1007/978-3-031-33455-9_13},
booktitle={The Semantic Web - 20th Extended Semantic Web Conference (ESWC 2023)},
publisher={Springer International Publishing}, author={KOUAGOU, N’Dah Jean and
Heindorf, Stefan and Demir, Caglar and Ngonga Ngomo, Axel-Cyrille}, editor={Pesquita,
Catia and Jimenez-Ruiz, Ernesto and McCusker, Jamie and Faria, Daniel and Dragoni,
Mauro and Dimou, Anastasia and Troncy, Raphael and Hertling, Sven}, year={2023},
pages={209–226} }'
chicago: KOUAGOU, N’Dah Jean, Stefan Heindorf, Caglar Demir, and Axel-Cyrille Ngonga
Ngomo. “Neural Class Expression Synthesis.” In The Semantic Web - 20th Extended
Semantic Web Conference (ESWC 2023), edited by Catia Pesquita, Ernesto Jimenez-Ruiz,
Jamie McCusker, Daniel Faria, Mauro Dragoni, Anastasia Dimou, Raphael Troncy,
and Sven Hertling, 13870:209–26. Springer International Publishing, 2023. https://doi.org/10.1007/978-3-031-33455-9_13.
ieee: 'N. J. KOUAGOU, S. Heindorf, C. Demir, and A.-C. Ngonga Ngomo, “Neural Class
Expression Synthesis,” in The Semantic Web - 20th Extended Semantic Web Conference
(ESWC 2023), Hersonissos, Crete, Greece, 2023, vol. 13870, pp. 209–226, doi:
https://doi.org/10.1007/978-3-031-33455-9_13.'
mla: KOUAGOU, N’Dah Jean, et al. “Neural Class Expression Synthesis.” The Semantic
Web - 20th Extended Semantic Web Conference (ESWC 2023), edited by Catia Pesquita
et al., vol. 13870, Springer International Publishing, 2023, pp. 209–26, doi:https://doi.org/10.1007/978-3-031-33455-9_13.
short: 'N.J. KOUAGOU, S. Heindorf, C. Demir, A.-C. Ngonga Ngomo, in: C. Pesquita,
E. Jimenez-Ruiz, J. McCusker, D. Faria, M. Dragoni, A. Dimou, R. Troncy, S. Hertling
(Eds.), The Semantic Web - 20th Extended Semantic Web Conference (ESWC 2023),
Springer International Publishing, 2023, pp. 209–226.'
conference:
end_date: 2023-06-01
location: Hersonissos, Crete, Greece
name: 20th Extended Semantic Web Conference
start_date: 2023-05-28
date_created: 2022-10-15T19:20:11Z
date_updated: 2023-07-02T18:10:02Z
department:
- _id: '574'
- _id: '760'
doi: https://doi.org/10.1007/978-3-031-33455-9_13
editor:
- first_name: Catia
full_name: Pesquita, Catia
last_name: Pesquita
- first_name: Ernesto
full_name: Jimenez-Ruiz, Ernesto
last_name: Jimenez-Ruiz
- first_name: Jamie
full_name: McCusker, Jamie
last_name: McCusker
- first_name: Daniel
full_name: Faria, Daniel
last_name: Faria
- first_name: Mauro
full_name: Dragoni, Mauro
last_name: Dragoni
- first_name: Anastasia
full_name: Dimou, Anastasia
last_name: Dimou
- first_name: Raphael
full_name: Troncy, Raphael
last_name: Troncy
- first_name: Sven
full_name: Hertling, Sven
last_name: Hertling
external_id:
unknown:
- https://link.springer.com/chapter/10.1007/978-3-031-33455-9_13
intvolume: ' 13870'
keyword:
- Neural network
- Concept learning
- Description logics
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://2023.eswc-conferences.org/wp-content/uploads/2023/05/paper_Kouagou_2023_Neural.pdf
oa: '1'
page: 209 - 226
project:
- _id: '410'
name: 'KnowGraphs: KnowGraphs: Knowledge Graphs at Scale'
- _id: '407'
grant_number: '101070305'
name: 'ENEXA: Efficient Explainable Learning on Knowledge Graphs'
- _id: '285'
grant_number: NW21-059D
name: 'SAIL: SAIL: SustAInable Life-cycle of Intelligent Socio-Technical Systems'
publication: The Semantic Web - 20th Extended Semantic Web Conference (ESWC 2023)
publication_identifier:
unknown:
- 978-3-031-33455-9
publication_status: published
publisher: Springer International Publishing
status: public
title: Neural Class Expression Synthesis
type: conference
user_id: '11871'
volume: 13870
year: '2023'
...
---
_id: '46243'
author:
- first_name: Caglar
full_name: Demir, Caglar
id: '43817'
last_name: Demir
- first_name: Axel-Cyrille
full_name: Ngonga Ngomo, Axel-Cyrille
last_name: Ngonga Ngomo
citation:
ama: Demir C, Ngonga Ngomo A-C. Clifford Embeddings – A Generalized Approach for
Embedding in Normed Algebras. ECML-PKDD. Published online 2023.
apa: Demir, C., & Ngonga Ngomo, A.-C. (2023). Clifford Embeddings – A Generalized
Approach for Embedding in Normed Algebras. ECML-PKDD. European Conference
on Machine Learning and Principles and Practice of Knowledge Discovery in Databases,
Torino.
bibtex: '@article{Demir_Ngonga Ngomo_2023, title={Clifford Embeddings – A Generalized
Approach for Embedding in Normed Algebras}, journal={ECML-PKDD}, author={Demir,
Caglar and Ngonga Ngomo, Axel-Cyrille}, year={2023} }'
chicago: Demir, Caglar, and Axel-Cyrille Ngonga Ngomo. “Clifford Embeddings – A
Generalized Approach for Embedding in Normed Algebras.” ECML-PKDD, 2023.
ieee: C. Demir and A.-C. Ngonga Ngomo, “Clifford Embeddings – A Generalized Approach
for Embedding in Normed Algebras,” ECML-PKDD, 2023.
mla: Demir, Caglar, and Axel-Cyrille Ngonga Ngomo. “Clifford Embeddings – A Generalized
Approach for Embedding in Normed Algebras.” ECML-PKDD, 2023.
short: C. Demir, A.-C. Ngonga Ngomo, ECML-PKDD (2023).
conference:
location: Torino
name: European Conference on Machine Learning and Principles and Practice of Knowledge
Discovery in Databases
date_created: 2023-08-01T09:12:06Z
date_updated: 2023-08-01T09:22:40Z
ddc:
- '000'
file:
- access_level: open_access
content_type: application/pdf
creator: cdemir
date_created: 2023-08-01T09:11:59Z
date_updated: 2023-08-01T09:11:59Z
file_id: '46244'
file_name: public.pdf
file_size: 408352
relation: main_file
file_date_updated: 2023-08-01T09:11:59Z
has_accepted_license: '1'
language:
- iso: eng
oa: '1'
project:
- _id: '407'
grant_number: '101070305'
name: 'ENEXA: Efficient Explainable Learning on Knowledge Graphs'
- _id: '410'
name: 'KnowGraphs: KnowGraphs: Knowledge Graphs at Scale'
- _id: '285'
grant_number: NW21-059D
name: 'SAIL: SAIL: SustAInable Life-cycle of Intelligent Socio-Technical Systems'
publication: ECML-PKDD
status: public
title: Clifford Embeddings – A Generalized Approach for Embedding in Normed Algebras
type: journal_article
user_id: '43817'
year: '2023'
...
---
_id: '46251'
author:
- first_name: Caglar
full_name: Demir, Caglar
id: '43817'
last_name: Demir
- first_name: Axel-Cyrille
full_name: Ngonga Ngomo, Axel-Cyrille
last_name: Ngonga Ngomo
citation:
ama: Demir C, Ngonga Ngomo A-C. Neuro-Symbolic Class Expression Learning. International
Joint Conference on Artificial Intelligence. Published online 2023.
apa: Demir, C., & Ngonga Ngomo, A.-C. (2023). Neuro-Symbolic Class Expression
Learning. International Joint Conference on Artificial Intelligence. International
Joint Conference on Artificial Intelligence IJCAI 2023, Macau.
bibtex: '@article{Demir_Ngonga Ngomo_2023, title={Neuro-Symbolic Class Expression
Learning}, journal={International Joint Conference on Artificial Intelligence},
author={Demir, Caglar and Ngonga Ngomo, Axel-Cyrille}, year={2023} }'
chicago: Demir, Caglar, and Axel-Cyrille Ngonga Ngomo. “Neuro-Symbolic Class Expression
Learning.” International Joint Conference on Artificial Intelligence, 2023.
ieee: C. Demir and A.-C. Ngonga Ngomo, “Neuro-Symbolic Class Expression Learning,”
International Joint Conference on Artificial Intelligence, 2023.
mla: Demir, Caglar, and Axel-Cyrille Ngonga Ngomo. “Neuro-Symbolic Class Expression
Learning.” International Joint Conference on Artificial Intelligence, 2023.
short: C. Demir, A.-C. Ngonga Ngomo, International Joint Conference on Artificial
Intelligence (2023).
conference:
location: Macau
name: International Joint Conference on Artificial Intelligence IJCAI 2023
date_created: 2023-08-01T09:30:37Z
date_updated: 2023-08-01T09:44:30Z
ddc:
- '000'
department:
- _id: '574'
file:
- access_level: open_access
content_type: application/pdf
creator: cdemir
date_created: 2023-08-01T09:30:35Z
date_updated: 2023-08-01T09:30:35Z
file_id: '46252'
file_name: public.pdf
file_size: 340865
relation: main_file
file_date_updated: 2023-08-01T09:30:35Z
has_accepted_license: '1'
language:
- iso: eng
oa: '1'
project:
- _id: '407'
grant_number: '101070305'
name: 'ENEXA: Efficient Explainable Learning on Knowledge Graphs'
- _id: '410'
name: 'KnowGraphs: KnowGraphs: Knowledge Graphs at Scale'
- _id: '285'
grant_number: NW21-059D
name: 'SAIL: SAIL: SustAInable Life-cycle of Intelligent Socio-Technical Systems'
publication: International Joint Conference on Artificial Intelligence
status: public
title: Neuro-Symbolic Class Expression Learning
type: journal_article
user_id: '43817'
year: '2023'
...
---
_id: '32509'
abstract:
- lang: eng
text: " We consider fact-checking approaches that aim to predict the veracity of
assertions in knowledge graphs. Five main categories of fact-checking approaches
for knowledge graphs have been proposed in the recent literature, of\r\nwhich
each is subject to partially overlapping limitations. In particular, current text-based
approaches are limited by manual feature engineering. Path-based and rule-based
approaches are limited by their exclusive use of knowledge graphs as background
knowledge, and embedding-based approaches suffer from low accuracy scores on current
fact-checking tasks. We propose a hybrid approach—dubbed HybridFC—that exploits
the diversity of existing categories of fact-checking approaches within an ensemble
learning setting to achieve a significantly better prediction performance. In
particular, our approach outperforms the state of the art by 0.14 to 0.27 in terms
of Area Under the Receiver Operating Characteristic curve on the FactBench dataset.
Our code is open-source and can be found at https://github.com/dice-group/HybridFC."
author:
- first_name: Umair
full_name: Qudus, Umair
id: '83392'
last_name: Qudus
orcid: 0000-0001-6714-8729
- first_name: Michael
full_name: Röder, Michael
id: '67199'
last_name: Röder
orcid: https://orcid.org/0000-0002-8609-8277
- first_name: Muhammad
full_name: Saleem, Muhammad
last_name: Saleem
- first_name: Axel-Cyrille
full_name: Ngonga Ngomo, Axel-Cyrille
id: '65716'
last_name: Ngonga Ngomo
citation:
ama: 'Qudus U, Röder M, Saleem M, Ngonga Ngomo A-C. HybridFC: A Hybrid Fact-Checking
Approach for Knowledge Graphs. In: Sattler U, Hogan A, Keet M, Presutti V, eds.
The Semantic Web -- ISWC 2022. Springer International Publishing; :462--480.
doi:10.1007/978-3-031-19433-7_27'
apa: 'Qudus, U., Röder, M., Saleem, M., & Ngonga Ngomo, A.-C. (n.d.). HybridFC:
A Hybrid Fact-Checking Approach for Knowledge Graphs. In U. Sattler, A. Hogan,
M. Keet, & V. Presutti (Eds.), The Semantic Web -- ISWC 2022 (pp. 462--480).
Springer International Publishing. https://doi.org/10.1007/978-3-031-19433-7_27'
bibtex: '@inproceedings{Qudus_Röder_Saleem_Ngonga Ngomo, place={Cham}, title={HybridFC:
A Hybrid Fact-Checking Approach for Knowledge Graphs}, DOI={10.1007/978-3-031-19433-7_27},
booktitle={The Semantic Web -- ISWC 2022}, publisher={Springer International Publishing},
author={Qudus, Umair and Röder, Michael and Saleem, Muhammad and Ngonga Ngomo,
Axel-Cyrille}, editor={Sattler, Ulrike and Hogan, Aidan and Keet, Maria and Presutti,
Valentina}, pages={462--480} }'
chicago: 'Qudus, Umair, Michael Röder, Muhammad Saleem, and Axel-Cyrille Ngonga
Ngomo. “HybridFC: A Hybrid Fact-Checking Approach for Knowledge Graphs.” In The
Semantic Web -- ISWC 2022, edited by Ulrike Sattler, Aidan Hogan, Maria Keet,
and Valentina Presutti, 462--480. Cham: Springer International Publishing, n.d.
https://doi.org/10.1007/978-3-031-19433-7_27.'
ieee: 'U. Qudus, M. Röder, M. Saleem, and A.-C. Ngonga Ngomo, “HybridFC: A Hybrid
Fact-Checking Approach for Knowledge Graphs,” in The Semantic Web -- ISWC 2022,
Hanghzou, China, pp. 462--480, doi: 10.1007/978-3-031-19433-7_27.'
mla: 'Qudus, Umair, et al. “HybridFC: A Hybrid Fact-Checking Approach for Knowledge
Graphs.” The Semantic Web -- ISWC 2022, edited by Ulrike Sattler et al.,
Springer International Publishing, pp. 462--480, doi:10.1007/978-3-031-19433-7_27.'
short: 'U. Qudus, M. Röder, M. Saleem, A.-C. Ngonga Ngomo, in: U. Sattler, A. Hogan,
M. Keet, V. Presutti (Eds.), The Semantic Web -- ISWC 2022, Springer International
Publishing, Cham, n.d., pp. 462--480.'
conference:
end_date: 2022-10-27
location: Hanghzou, China
name: International Semantic Web Conference (ISWC)
start_date: 2022-10-23
date_created: 2022-08-02T11:56:03Z
date_updated: 2025-09-11T09:37:16Z
ddc:
- '000'
department:
- _id: '34'
doi: 10.1007/978-3-031-19433-7_27
editor:
- first_name: Ulrike
full_name: Sattler, Ulrike
last_name: Sattler
- first_name: Aidan
full_name: Hogan, Aidan
last_name: Hogan
- first_name: Maria
full_name: Keet, Maria
last_name: Keet
- first_name: Valentina
full_name: Presutti, Valentina
last_name: Presutti
file:
- access_level: closed
content_type: application/pdf
creator: uqudus
date_created: 2022-12-22T15:45:29Z
date_updated: 2022-12-22T15:45:29Z
file_id: '34853'
file_name: hybrid_fact_check_iswc2022.pdf
file_size: 296218
relation: main_file
success: 1
file_date_updated: 2022-12-22T15:45:29Z
has_accepted_license: '1'
keyword:
- fact checking · ensemble learning · knowledge graph veracit
language:
- iso: eng
page: 462--480
place: Cham
popular_science: '1'
project:
- _id: '410'
name: 'KnowGraphs: KnowGraphs: Knowledge Graphs at Scale'
publication: The Semantic Web -- ISWC 2022
publication_identifier:
isbn:
- 978-3-031-19433-7
publication_status: accepted
publisher: Springer International Publishing
quality_controlled: '1'
status: public
title: 'HybridFC: A Hybrid Fact-Checking Approach for Knowledge Graphs'
type: conference
user_id: '83392'
year: '2022'
...
---
_id: '25212'
abstract:
- lang: eng
text: "Finding a good query plan is key to the optimization of query runtime. This
holds in particular for cost-based federation\r\nengines, which make use of cardinality
estimations to achieve this goal. A number of studies compare SPARQL federation
engines across different performance metrics, including query runtime, result
set completeness and correctness, number of sources selected and number of requests
sent. Albeit informative, these metrics are generic and unable to quantify and
evaluate the accuracy of the cardinality estimators of cost-based federation engines.
To thoroughly evaluate cost-based federation engines, the effect of estimated
cardinality errors on the overall query runtime performance must be measured.
In this paper, we address this challenge by presenting novel evaluation metrics
targeted at a fine-grained benchmarking of cost-based federated SPARQL query engines.
We evaluate five cost-based federated SPARQL query engines using existing as well
as novel evaluation metrics by using LargeRDFBench queries. Our results provide
a detailed analysis of the experimental outcomes that reveal novel insights, useful
for the development of future cost-based federated SPARQL query processing engines."
article_type: original
author:
- first_name: Umair
full_name: Qudus, Umair
id: '83392'
last_name: Qudus
orcid: 0000-0001-6714-8729
- first_name: Muhammad
full_name: Saleem, Muhammad
last_name: Saleem
- first_name: Axel-Cyrille
full_name: Ngonga Ngomo, Axel-Cyrille
id: '65716'
last_name: Ngonga Ngomo
- first_name: Young-Koo
full_name: Lee, Young-Koo
last_name: Lee
citation:
ama: Qudus U, Saleem M, Ngonga Ngomo A-C, Lee Y-K. An Empirical Evaluation of Cost-based
Federated SPARQL Query Processing Engines. Semantic Web. 12(6):843-868.
doi:10.3233/SW-200420
apa: Qudus, U., Saleem, M., Ngonga Ngomo, A.-C., & Lee, Y.-K. (n.d.). An Empirical
Evaluation of Cost-based Federated SPARQL Query Processing Engines. Semantic
Web, 12(6), 843–868. https://doi.org/10.3233/SW-200420
bibtex: '@article{Qudus_Saleem_Ngonga Ngomo_Lee, title={An Empirical Evaluation
of Cost-based Federated SPARQL Query Processing Engines}, volume={12}, DOI={10.3233/SW-200420}, number={6}, journal={Semantic
Web}, publisher={ISO Press}, author={Qudus, Umair and Saleem, Muhammad and Ngonga
Ngomo, Axel-Cyrille and Lee, Young-Koo}, pages={843–868} }'
chicago: 'Qudus, Umair, Muhammad Saleem, Axel-Cyrille Ngonga Ngomo, and Young-Koo
Lee. “An Empirical Evaluation of Cost-Based Federated SPARQL Query Processing
Engines.” Semantic Web 12, no. 6 (n.d.): 843–68. https://doi.org/10.3233/SW-200420.'
ieee: 'U. Qudus, M. Saleem, A.-C. Ngonga Ngomo, and Y.-K. Lee, “An Empirical Evaluation
of Cost-based Federated SPARQL Query Processing Engines,” Semantic Web,
vol. 12, no. 6, pp. 843–868, doi: 10.3233/SW-200420.'
mla: Qudus, Umair, et al. “An Empirical Evaluation of Cost-Based Federated SPARQL
Query Processing Engines.” Semantic Web, vol. 12, no. 6, ISO Press, pp.
843–68, doi:10.3233/SW-200420.
short: U. Qudus, M. Saleem, A.-C. Ngonga Ngomo, Y.-K. Lee, Semantic Web 12 (n.d.)
843–868.
date_created: 2021-10-01T06:52:52Z
date_updated: 2025-09-11T09:50:14Z
ddc:
- '000'
department:
- _id: '574'
doi: 10.3233/SW-200420
file:
- access_level: closed
content_type: application/pdf
creator: uqudus
date_created: 2024-01-13T11:35:53Z
date_updated: 2024-01-13T11:35:53Z
file_id: '50483'
file_name: swj2604.pdf
file_size: 978478
relation: main_file
success: 1
file_date_updated: 2024-01-13T11:35:53Z
has_accepted_license: '1'
intvolume: ' 12'
issue: '6'
keyword:
- SPARQL
- benchmarking
- cost-based
- cost-free
- federated
- querying
language:
- iso: eng
page: 843-868
project:
- _id: '410'
name: 'KnowGraphs: KnowGraphs: Knowledge Graphs at Scale'
publication: Semantic Web
publication_identifier:
issn:
- 2210-4968
publication_status: accepted
publisher: ISO Press
status: public
title: An Empirical Evaluation of Cost-based Federated SPARQL Query Processing Engines
type: journal_article
user_id: '83392'
volume: 12
year: '2021'
...