TY - CONF 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 A2 - Arampatzis, Avi A2 - Kanoulas, Evangelos A2 - Tsikrika, Theodora A2 - Vrochidis, Stefanos A2 - Giachanou, Anastasia A2 - Li, Dan A2 - Aliannejadi, Mohammad A2 - Vlachos, Michalis A2 - Faggioli, Guglielmo A2 - 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 UR - https://opus4.kobv.de/opus4-fhpotsdam/frontdoor/index/index/docId/3295 SN - 978-3-031-42448-9 SN - 1611-3349 SP - 251 EP - 275 PB - Springer International Publishing CY - Cham ER -