Hypothesizing that some verb senses and argument roles defined in VerbNet (Schuler, 2005) are useful for identifying text spans corresponding to opinions and their arguments as well as their relationships 4 , we introduce three constraints that exploit the PropBank-style semantic role labels provided by Mate Tools (Björkelund et al., 2009).
constraint (6) states that (1) a span candidate associated with a particular verb sense should be assigned a non-none label, and (2) a span candidate associated with a verb argument should be assigned a non-none label.