Yelena Mejova is a Research Leader at the ISI Foundation in Turin, Italy, a part of the Digital Epidemiology group (previously, a scientist at the Qatar Computing Research Institute, Qatar). Specializing in social media analysis and mining, her work concerns the quantification of health and wellbeing signals in social media, as well as tracking of social phenomena, including politics and news consumption. She co-edited a volume on the use of Twitter for social science in “Twitter: A Digital Socioscope”, and a special issue of Social Science Computer Review on Quantifying Politics Using Online Data. Previously, as a postdoctoral member of the Web Mining team at Yahoo! Research Barcelona, Yelena participated in the Linguistically Motivated Semantic Aggregation Engines (LiMoSINe) EU project. Also, Yelena has published widely on sentiment analysis and its application to social media and political speech.