Evaluate the collective function of references cited together in a given text segment.
Classify their combined role into one of the following categories: 'method', 'background', or 'result'.

Text:We then trained the unlexicalised parsers BitPar (Schmid, 2004) and LoPar (Schmid, 2000), and the Stanford parser (Klein and Manning, 2003) in its lexicalised and Markovised form14 on the training set and tested them on the 2000 test sentences as well as on the 200 TePaCoC sentences.
Category: