What Happened in CLEF... For a While? -- Crosslingual depression detection in Twitter using bilingual word alignments -- Studying the Variability of System Setting Effectiveness by Data Analytics and Visualization -- Stance Detection in Web and Social Media : A Comparative Study -- TwitCID: a Collection of Data Sets for Studies on Information Diffusion on Social Networks -- Sonny, Cerca! Evaluating the Impact of Using a Vocal Assistant to Search at School -- Generating Cross-Domain Text Corpora from Social Media Comments -- Efficient Answer-Annotation for Frequent Questions -- Improving Ranking for Systematic Reviews Using Query Adaptation -- Analyzing the adequacy of readability indicators to a non-English language -- How many labels? Determining the Number of Labels in Multi-Label Text Classification -- Using Audio Transformations to Improve Comprehension in Voice Question Answering -- A User Modeling Shared Challenge Proposal -- How Lexical Gold Standards Have Effects On The Usefulness Of Text Analysis Tools For Digital Scholarship -- Personality facets recognition from text -- Unsupervised System Combination for Set-based Retrieval with Expectation Maximization -- An Ensemble Approach to Cross-Domain Authorship Attribution -- Evaluation of Deep Species Distribution Models using Environment and Co-occurrences -- Interactive Learning-based Retrieval Technique for Visual Lifelogging -- An Effective Deep Transfer Learning and Information Fusion Framework for Medical Visual Question Answering -- Language Modeling in Temporal Mood Variation Models for Early Risk Detection on The Internet -- Medical Image Labeling and Semantic Understanding for Clinical Applications -- To Check or not to Check: Syntax, Semantics, and Context in the Language of Check-worthy Claims -- Overview of CENTRE@CLEF 2019: Sequel in the Systematic Reproducibility Realm -- Overview of the CLEF-2019 CheckThat!: Automatic Identification and Verification of Claims -- Overview of the CLEF eHealth Evaluation Lab 2019 -- Overview of eRisk 2019: Early Risk Prediction on the Internet -- ImageCLEF 2019: Multimedia Retrieval in Medicine, Lifelogging, Security and Nature -- Overview of LifeCLEF 2019: Identification of Amazonian Plants, South & North American Birds, and Niche Prediction -- Overview of PAN 2019: Bots and Gender Profiling, Celebrity Profiling, Cross-domain Authorship Attribution and Style Change Detection -- Overview of the CLEF 2019 Personalised Information Retrieval Lab (PIR-CLEF 2019) -- Overview of CLEF 2019 Lab ProtestNews: Extracting Protests from News in a Cross-context Setting.