text: Anna Rogers 
  Center for Social Data Science 
  University of Copenhagen 
  arogers@sodas.ku.dk  Olga Kovaleva 
  Dept. of Computer Science 
  University of Massachusetts Lowell 
  okovalev@cs.uml.edu  Anna Rumshisky 
  Dept. of Computer Science 
  University of Massachusetts Lowell 
  arum@cs.uml.edu 