Unni Cathrine Eiken February 2005

process. To be as useful as possible, the meaning structures should be normalised and
generalisable.
The examples above show how normalisation through use of EPAS realises the concept of
canonical form to some degree and seems particularly useful for the purpose of the present
work. By using grammatic relations such as subject and object as reference points, semantically
equivalent sentences, such as (3-2a) and (3-2b), would be given different meaning structures due
to the difference in verbal voice. Structuring the meanings conveyed with the sentences in (3-2)
within a grammatical relations paradigm would make it necessary to mark the verbal voice as
well as the grammatical relations. In addition, active and passive structures would have to be
treated differently in the subsequent analysis. Basing the extraction merely on syntactic
properties of the sentences in the corpus would make the extracted material very difficult to
classify, mainly because similar meanings would be represented differently.
The advantages of a normalised and generalisable dataset is further clarified by the following
example. Upon a simple grammatical analysis, the sentences shown in (3- 2) can be categorised
based on the syntactic roles predicate, subject and object. The result of such a classification is
shown in examples (3-5) and (3-6):
(3- 5)
predicate subject object
a. drepe morder kvinne
kill
b. drepe
kill
c. drepe
kill
murderer
kvinne
woman
kvinne
woman
woman
murderer
murderer
?
The structures in (3-5) above can be extracted upon part of speech tagging of the sentences in
(3-2). The active and passive predicate receives the same structure, and as no semantic
information is available, the structuring of the arguments is in accordance with their status as
subject or object. Attempting to classify these subjects and objects based on their co-occurrence
with the predicate produces groupings of words which are not directly generalisable. Murderer
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