Connection Relations and Quantifier Scope

CONNECTION RELATIONS AND QUANTIFIER SCOPE Long-in Latecki University of Hamburg Department of Computer Science Bodenstedtstr~ 16, 2000 Hamburg 50, Germany e-mail: latecki@rz.informatik.uni-hamburg.dbp.de ABSTRACT A formalism will be presented in this paper which makes it possible to realise the idea of assigning only one scope-ambiguous representation to a sentence that is ambiguous with regard to quantifier scope. The scope determination results in extending this representation with additional context and world knowledge conditions. If there is no scope determining information, the formalism can work further with this scope-ambiguous representation. Thus scope information does not have to be completely determined. 0. INTRODUCTION Many natural language sentences have more than one possible reading with regard to quantifier scope. The most widely used methods for scope determination generate all possible readings of a sentence with regard to quantifier scope by applying all quantifiers which occur in the sentence in all combinatorically possible sequences. These methods do not make use of the inner structure and meaning of a quantifier. At best, quantifiers are constrained by external conditions in order to eliminate some scope relations. The best known methods are: determination of scope in LF in GB (May 1985), Cooper Storage (Cooper 1983, Keller 1988) and the algorithm of Hobbs and Shieber (Hobbs/Shieber 1987). These methods assign, for instance, six possible readings to a sentence with three quantifiers. Using these methods, a sentence must be disambiguated in order to receive a semantic representation. This means that a scope-ambiguous sentence necessarily has several semantic representations, since the formalisms for the representation do not allow for scope-ambiguity. It is hard to imagine that human beings disambiguate scope-ambiguous sentences in the same way. The generation of all possible combinations of sequences of quantifiers and the assignment of these sequences to various readings seems to be cognitively inadequate. The problem becomes even more complicated when natural language quantifiers can be interpreted distributively as well as collectively, which can also lead to further readings. Let us take the following sentence from Kempson/Cormack (1981) as an example: Two examiners marked six scripts. The two quantifying noun phrases can in this case be interpreted either distributively or collectively. The quantifier two examiners can have wide scope over the quantifier six scripts, or vice versa, which all in all can lead to various readings. Kempson and Cormack assign four possible readings to this sentence, 241 Davies (1989) even eight. (A detailed discussion will follow.) No one, however, will make the claim that people will first assign all possible representations with regard to the scope of the quantifiers and their distribution, and will then eliminate certain interpretations according to the context; but this is today's standard procedure in linguistics. In many cases, it is also almost impossible to determine a preferred reading. The difficulties that people have when they are forced to disambiguate such sentences (to explicate all possible readings) point to the fact that people only assign an under- determined scope-ambiguous representation in the first place. Such a representation of the example sentence would only …

Content truncated to 500 words