Some of our partners are:

  • Center for the Study of Democracy – disinformation and policy research;
  • Ontotext – semantically-enriched database of debunks, AI tools for content verification;
  • Prof. Nicoleta Corbu (College of Communication and Public Relations, SNSPA) – extensive research in the field of political communication, with a focus on media effects, disinformation, and news consumption.
  • Funky Citizens – media literacy in the Balkans, running the political fact-checking platform in Romania;
  • Dr Ralitsa Kovacheva – journalism research in hybrid threats;
  • Dr Bissera Zankova – Media 21 Foundation – media freedom; media literacy; law.

Under the leadership of Prof. Kalina Bontcheva, we established a new regional multi-disciplinary alliance of researchers, fact-checkers and other experts, to act as a catalyst and an amplifier of national and regional actions against disinformation.

Key staff

Prof. Kalina Bontcheva is the Research Leader on disinformation at the Big Data for Smart Society Institute, as well as the head of the Natural Language Processing (NLP) group at the University of Sheffield. She has coordinated the FP7 PHEME project on rumour and disinformation analysis and is the scientific director of the H2020 WeVerify project on collaborative content verification. Since 2014, Prof. Bontcheva has been researching methods for disinformation analysis combining NLP methods for analysing the textual content with machine learning models for credibility, veracity, and stance detection. These are combined also with the analysis of the mention and hashtag-based networks, in the context of misinformation spread, voting intentions and online abuse.

Prof. Ivan Koychev is the Data Analytics research group leader and leads the MSc. Program in Information Retrieval and Knowledge Discovery. He gained experience in a number of academic and industrial projects including contribution to seven EU funded projects. His main research interests are in the areas of Machine Learning, AI, Information Retrieval, Data/Text Mining and their applications to disinformation analysis. He also brings in a strong track record in Natural Language Processing in Bulgarian and English. His most recent publications have focused on deep learning methods for check worthiness analysis (i.e. whether a given post needs to be fact-checked or not), detection of deception in political debates, verification of claims about images, and detection of toxicity in news articles.

Selected publications

  1. Carolina Scarton, Diego F. Silva, Kalina Bontcheva. Measuring What Counts: The case of Rumour Stance Classification. Proc. of the 1st Conference of the Asia-Pacific Chapter of the Association for Computational Linguistics and the 10th International Joint Conference on Natural Language Processing (AACL-IJNLP), 2020,
  2. Alex Nikolov, Giovanni Da San Martino, Ivan Koychev, Preslav Nakov, Team Alex at CLEF CheckThat! 2020: Identifying Check-Worthy Tweets With Transformer Models, CLEF 2020, 22-25 September 2020, Thessaloniki, Greece.,
  3. Dimitrina Zlatkova, Preslav Nakov, Ivan Koychev, Fact-Checking Meets Fauxtography: Verifying Claims About Images, Proc. EMNLP-IJCNLP, Publisher: Association for Computational Linguistics, 2019, doi:10.18653/v1/D19-1216,
  4. Michal Lukasik, Kalina Bontcheva, Trevor Cohn, Arkaitz Zubiaga, Maria Liakata, Rob Procter. Gaussian processes for rumour stance classification in social media. ACM Transactions on Information Systems (TOIS) 37 (2), 1-24. 2019.
  5. Ahmet Aker, A Sliwa, F Dalvi, Kalina Bontcheva. Rumour verification through recurring information and an inner-attention mechanism. Online Social Networks and Media 13, 100045. 2019.
  6. Todor Mihaylov, Tsvetomila Mihaylova, Preslav Nakov, Lluís Màrquez, Georgi D. Georgiev, Ivan Koychev, The dark side of news community forums: opinion manipulation trolls, Internet Research, vol:28, issue:5, 2018, pages:1292-1312, ISSN (online):1066-2243,,


Kalina Bontcheva,