Underspecified changes: a dynamic, probabilistic frame theory for verbs

Abstract

The verb ‘rise’ can be used both with property-denoting nouns like ‘temperature’
but also with NPs like ‘a Titan’ or ‘China’. Whereas in the former case the change triggered
by a rising event is directly related to the subject (its current value increases), this does not
hold for ‘a titan’ or ‘China’. In this case it is a property of these objects, say their height or
their political power, which increases in value. Furthermore, ‘rise’ does not target a particular
property as the examples above show. This data has led Cooper (2010) to the conclusion that
it is presumably not possible (i) “to extract a single general meaning of words which covers all
the particular meanings of the word in context”, and (ii) “to determine once and for all the set
of particular contextually determined meanings of a word”. In this article we present a solution
to the two problems raised by ‘rise’ in a frame theory. ‘Rise’ is analyzed as a scalar verb which
does not lexicalize a complete scale in its meaning. Rather, it shows underspecification relative
to the dimension (property) parameter of a scale. The set of admissible properties is determined
by a constraint on the value ranges of properties. If the property is not uniquely determined
by the subject, the comprehender uses probabilistic reasoning based on world knowledge and
discourse information to defeasibly infer the most likely candidates from this set (2nd problem).
The first problem is solved not by simply introducing objects into the representation of a
discourse but instead by pairs consisting of an object and an associated frame component which
collects the object information contributed by the discourse. Changes triggered by events like
the one denoted by ‘rise’ are modelled as update operations on the frame component while the
object component is left unchanged.
Keywords: lexical semantics, scalar changes, frame theory, probabilities.