TY - CHAP A1 - Barrón-Cedeño, Alberto A1 - Alam, Firoj A1 - Galassi, Andrea A1 - Da San Martino, Giovanni A1 - Nakov, Preslav A1 - Elsayed, Tamer A1 - Azizov, Dilshod A1 - Caselli, Tommaso A1 - Cheema, Gullal S. A1 - Haouari, Fatima A1 - Hasanain, Maram A1 - Kutlu, Mucahid A1 - Li, Chengkai A1 - Ruggeri, Federico A1 - Struß, Julia Maria A1 - Zaghouani, Wajdi ED - Arampatzis, Avi ED - Kanoulas, Evangelos ED - Tsikrika, Theodora ED - Vrochidis, Stefanos ED - Giachanou, Anastasia ED - Li, Dan ED - Aliannejadi, Mohammad ED - Vlachos, Michalis ED - Faggioli, Guglielmo ED - Ferro, Nicola T1 - Overview of the CLEF–2023 CheckThat! Lab on Checkworthiness, Subjectivity, Political Bias, Factuality, and Authority of News Articles and Their Source T2 - Experimental IR Meets Multilinguality, Multimodality, and Interaction N2 - We describe the sixth edition of the CheckThat! lab, part of the 2023 Conference and Labs of the Evaluation Forum (CLEF). The five previous editions of CheckThat! focused on the main tasks of the information verification pipeline: check-worthiness, verifying whether a claim was fact-checked before, supporting evidence retrieval, and claim verification. In this sixth edition, we zoom into some new problems and for the first time we offer five tasks in seven languages: Arabic, Dutch, English, German, Italian, Spanish, and Turkish. Task 1 asks to determine whether an item - text or text plus image- is check-worthy. Task 2 aims to predict whether a sentence from a news article is subjective or not. Task 3 asks to assess the political bias of the news at the article and at the media outlet level. Task 4 focuses on the factuality of reporting of news media. Finally, Task 5 looks at identifying authorities in Twitter that could help verify a given target claim. For a second year, CheckThat! was the most popular lab at CLEF-2023 in terms of team registrations: 127 teams. About one-third of them (a total of 37) actually participated. KW - Desinformation KW - Fehlinformation KW - COVID-19 Y1 - 2023 SN - 978-3-031-42448-9 U6 - https://doi.org/10.1007/978-3-031-42448-9_20 SN - 1611-3349 SP - 251 EP - 275 PB - Springer International Publishing CY - Cham ER - TY - CHAP A1 - Galassi, Andrea A1 - Ruggeri, Federico A1 - Barrón-Cedeño, Alberto A1 - Alam, Firoj A1 - Caselli, Tommaso A1 - Kutlu, Mucahid A1 - Struß, Julia Maria A1 - Antici, Francesco A1 - Hasanain, Maram A1 - Köhler, Juliane A1 - Korre, Katerina A1 - Leistra, Folkert A1 - Muti, Arianna A1 - Siegel, Melanie A1 - Türkmen, Mehmet Deniz A1 - Wiegand, Michael A1 - Zaghouani, Wajdi ED - Aliannejadi, Mohammad ED - Faggiolo, Guglielmo ED - Ferro, Nicola ED - Vlachos, Michalis T1 - Overview of the CLEF-2023 CheckThat! Lab: Task 2 on Subjectivity in News Articles BT - Notebook for the CheckThat! Lab at CLEF 2023 T2 - CLEF 2023 Working Notes N2 - We describe the outcome of the 2023 edition of the CheckThat!Lab at CLEF. We focus on subjectivity (Task 2), which has been proposed for the first time. It aims at fostering the technology for the identification of subjective text fragments in news articles. For that, we produced corpora consisting of 9,530 manually-annotated sentences, covering six languages - Arabic, Dutch, English, German, Italian, and Turkish. Task 2 attracted 12 teams, which submitted a total of 40 final runs covering all languages. The most successful approaches addressed the task using state-of-the-art multilingual transformer models, which were fine-tuned on language-specific data. Teams also experimented with a rich set of other neural architectures, including foundation models, zero-shot classifiers, and standard transformers, mainly coupled with data augmentation and multilingual training strategies to address class imbalance. We publicly release all the datasets and evaluation scripts, with the purpose of promoting further research on this topic. KW - Desinformation KW - Fehlinformation KW - COVID-19 Y1 - 2023 UR - https://ceur-ws.org/Vol-3497/paper-020.pdf SP - 236 EP - 249 CY - Thessaloniki ER - TY - CHAP A1 - Nakov, Preslav A1 - Barrón-Cedño, Alberto A1 - Da San Martino, Giovanni A1 - Alam, Firoj A1 - Struß, Julia Maria A1 - Mandl, Thomas A1 - Míguez, Rubén A1 - Caselli, Tommaso A1 - Kutlu, Mucahid A1 - Zaghouani, Wajdi A1 - Li, Chengkai A1 - Shaar, Shaden A1 - Shahi, Gautam Kishore A1 - Mubarak, Hamdy A1 - Nikolov, Alex A1 - Babulkov, Nikolay A1 - Kartal, Yavuz Selim A1 - Beltrán, Javier T1 - The CLEF-2022 CheckThat! Lab on Fighting the COVID-19 Infodemic and Fake News Detection T2 - Advances in Information Retrieval. ECIR 2022 N2 - The fifth edition of the CheckThat! Lab is held as part of the 2022 Conference and Labs of the Evaluation Forum (CLEF). The lab evaluates technology supporting various factuality tasks in seven languages: Arabic, Bulgarian, Dutch, English, German, Spanish, and Turkish. Task 1 focuses on disinformation related to the ongoing COVID-19 infodemic and politics, and asks to predict whether a tweet is worth fact-checking, contains a verifiable factual claim, is harmful to the society, or is of interest to policy makers and why. Task 2 asks to retrieve claims that have been previously fact-checked and that could be useful to verify the claim in a tweet. Task 3 is to predict the veracity of a news article. Tasks 1 and 3 are classification problems, while Task 2 is a ranking one. KW - Desinformation KW - Fehlinformation KW - COVID-19 KW - Fact-checking KW - Check-worthiness estimation Y1 - 2022 SN - 978-3-030-99739-7 U6 - https://doi.org/10.1007/978-3-030-99739-7_52 SN - 0302-9743 SP - 416 EP - 428 PB - Springer CY - Cham ER - TY - CHAP A1 - Nakov, Preslav A1 - Barrón-Cedño, Alberto A1 - Da San Martino, Giovanni A1 - Alam, Firoj A1 - Struß, Julia Maria A1 - Mandl, Thomas A1 - Míguez, Rubén A1 - Caselli, Tommaso A1 - Kutlu, Mucahid A1 - Zaghouani, Wajdi A1 - Li, Chengkai A1 - Shaar, Shaden A1 - Shahi, Gautam Kishore A1 - Mubarak, Hamdy A1 - Nikolov, Alex A1 - Babulkov, Nikolay A1 - Kartal, Yavuz Selim A1 - Wiegand, Michael A1 - Siegel, Melanie A1 - Köhler, Juliane T1 - Overview of the CLEF-2022 CheckThat! Lab on Fighting the COVID-19 Infodemic and Fake News Detection T2 - Experimental IR Meets Multilinguality, Multimodality, and Interaction. CLEF 2022. N2 - We describe the fifth edition of the CheckThat! lab, part of the 2022 Conference and Labs of the Evaluation Forum (CLEF). The lab evaluates technology supporting tasks related to factuality in multiple languages: Arabic, Bulgarian, Dutch, English, German, Spanish, and Turkish. Task 1 asks to identify relevant claims in tweets in terms of check-worthiness, verifiability, harmfullness, and attention-worthiness. Task 2 asks to detect previously fact-checked claims that could be relevant to fact-check a new claim. It targets both tweets and political debates/speeches. Task 3 asks to predict the veracity of the main claim in a news article. CheckThat! was the most popular lab at CLEF-2022 in terms of team registrations: 137 teams. More than one-third (37%) of them actually participated: 18, 7, and 26 teams submitted 210, 37, and 126 official runs for tasks 1, 2, and 3, respectively. KW - Check-worthiness estimation KW - Fact-checking KW - Desinformation KW - Fehlinformation KW - COVID-19 Y1 - 2022 SN - 978-3-031-13643-6 U6 - https://doi.org/10.1007/978-3-031-13643-6_29 SN - 0302-9743 SP - 495 EP - 520 PB - Springer CY - Cham ER - TY - CHAP A1 - Nakov, Preslav A1 - Da San Martino, Giovanni A1 - Elsayed, Tamer A1 - Barrón-Cedeño, Alberto A1 - Míguez, Rubén A1 - Shaar, Shaden A1 - Alam, Firoj A1 - Haouari, Fatima A1 - Hasanain, Maram A1 - Mansour, Watheq A1 - Hamdan, Bayan A1 - Sheikh Ali, Zien A1 - Babulkov, Nikolay A1 - Nikolov, Alex A1 - Koshore Shahi, Gautam A1 - Struß, Julia Maria A1 - Mandl, Thomas A1 - Kutlu, Mucahid A1 - Selim Kartal, Yavuz T1 - Overview of the CLEF–2021 CheckThat! Lab on Detecting Check-Worthy Claims, Previously Fact-Checked Claims, and Fake News T2 - Experimental IR Meets Multilinguality, Multimodality, and Interaction N2 - We describe the fourth edition of the CheckThat! Lab, part of the 2021 Conference and Labs of the Evaluation Forum (CLEF). The lab evaluates technology supporting tasks related to factuality, and covers Arabic, Bulgarian, English, Spanish, and Turkish. Task 1 asks to predict which posts in a Twitter stream are worth fact-checking, focusing on COVID-19 and politics (in all five languages). Task 2 asks to determine whether a claim in a tweet can be verified using a set of previously fact-checked claims (in Arabic and English). Task 3 asks to predict the veracity of a news article and its topical domain (in English). The evaluation is based on mean average precision or precision at rank k for the ranking tasks, and macro-F1 for the classification tasks. This was the most popular CLEF-2021 lab in terms of team registrations: 132 teams. Nearly one-third of them participated: 15, 5, and 25 teams submitted official runs for tasks 1, 2, and 3, respectively. KW - Fact-checking KW - Check-worthiness estimation KW - Desinformation KW - Fehlinformation Y1 - 2021 SN - 978-3-030-85251-1 U6 - https://doi.org/10.1007/978-3-030-85251-1_19 SP - 264 EP - 291 PB - Springer CY - Cham ER -