Eckhard Bick - VISL

modify a lexicon entry. Quantitative evaluation will be affected “locally”, i.e. for the
valency pattern of individual lexemes (e.g. the frequency of ‘dormir’ with a direct
object), not for categorical conclusions (e.g. the frequency of @ACC or as such).
If valency statistics for individual lexemes is mandatory, two solutions offer
themselves:
(a) A qualitative valency analysis of the corpus is done first, i.e. the automatically
extracted lexical valency patterns are automatically compared to those found in the
lexicon, and all differences inspected manually and added to the lexicon, where they are
deemed to contain “new” valency information rather than plain erroneous tagging. After
this, a new, quantitative, run is performed.
(b) False positive valency readings (e.g. superfluous @ACC due to a wrong
mark on the main verb) - especially unambiguous false positive readings - are extremely
rare due to the “negative” way a cautious CG works - it relies mostly on REMOVE
rules and the correct syntactic tag will survive (alongside or instead of, for instance, a
false @ACC), since there would be nothing in the syntactic context calling for its
removal. False negative valency readings (e.g. no @ACC because of a lacking
mark) are more common, but will often lead to the survival of a “dummy” tag (@NPHR
for nominal, @ADVL for adverbial material), which is used as function labels for the
top node of utterances without a verbal top node. Now, sentences containing extra
dummy labels can be filtered automatically, inspected and used to correct the individual
lexeme valency statistics.
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