Unni Cathrine Eiken February 2005

consist of, or to make use of a component that predicts the part of speech of an unknown word.
One solution that would have been suitable for the purposes of the present work would be to
assume that all unknown words were nouns. However, due to the small size of the corpus used
for this project, none of these strategies were implemented, and unknown words were added to
the lexicon by hand.
When parsing texts with NorGram and XLE, the user has several choices with regards to the
format of the final syntactic analysis. For example, it is possible to receive partial parses, or to
let the system return all the potential analyses of the input sentence. For the purposes of this
project, I received full parses of each sentence in the text material and chose to manually check
each instance where the system returned multiple valid parses and actively decided on the
correct one that I wished to extract the EPAS from.
3.3.2 Extracting EPAS from NorGram
The output provided by XLE upon a successful parse using the NorGram grammar is
particularly useful for a subsequent extraction of EPAS. NorGram is based on the LFG grammar
formalism and produces constituent structures (c-structures), functional structures (f-structures)
and minimal recursion semantics structures (MRS-structures) upon parsing a sentence. Each of
these outputs can be useful for a subsequent extraction of predicates and their arguments.
The c-structure in LFG is an external structure which displays an ordered representation of the
words in a sentence or phrase (Bresnan 2001, p. 44). In XLE, the c-structure is represented by a
phrase structure tree, where the terminal nodes are fully inflected word forms. F-structures
represent the internal structure of a sentence. On this level, the “syntactic functions are
associated with semantic predicate argument relations” (Bresnan 2001, p. 45). C-structures and
f-structures are different structures, but display parallel information. Figure 3 below shows the
graphical representation of the c- and f-structures for the sentence Politiet leter etter morderen
(The police is looking for the murderer) generated by NorGram.
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