Definition5. (Sentiment Time Series) is a sequence of values s i computed by aggregating sentiments on a time interval p, using fixed sub-intervals p i of the same length: s i =s(d, p i).
Our further analysis of sentiment dynamics is centered on sentiment time series for a given group, topic and time period. Before going into details about the right time granularity and a sentiment correlation function, we consider the relations between demographic groups, and discuss how they affect the formulation of our problem.