Designing an Anaphora Resolution Algorithm for Route Instructions

eflects a preference for some of the possible interpretations as the antecedent of the
anaphor in these constructions cannot be defined exactly.
The fifth rule defines how the algorithm works if the anaphor occurs as
Argument of a Conjunction like in the following example.
13) don’t turn right there, instead of that go straight past the post office
As conjunctions connect clauses (which refer to event, fact, proposition etc),
anaphors occurring in the argument position of a conjunction are classified as I-
incompatible and they are resolved to the element in the A-List.
The sixth rule copes with constructions in which the anaphor occurs as Object
of a Spatial PP. If this is the case, the anaphor generally refers to a concrete,
individual object even though the lexical entry of most of the prepositions marks the
preposition as ambiguous because they can be combined either with individual or
with abstract entities. In the following examples the anaphor is ambiguous because it
is the object of an ‘into’-, ‘in’-, ‘before’- or ‘after’-PP. The object of these
prepositions is either an abstract object as in “go into/in the middle” or it is a
concrete, individual entity as in “go into/in the car park”. ‘After’ and ‘before’ are
also ambiguous but in a different way because they are used as prepositions or as
conjunctions. If they function as prepositions their object refers to concrete,
individual objects while arguments of conjunctions refer to abstract objects. Again,
this rule is defined with respect to the domain so that it cannot be generalised and
transferred into other domains.
3.4 Salience-List, Implicit S-List and Abstract-Object-List
The Salience-List (S-List) includes all discourse entities which match the constraints
of the anaphor actually processed and which are highly salient at this processing point
in the discourse. As previously explained, applying selectional restrictions rules and
employing inference mechanisms not only defines the properties of the entities stored
in the discourse model but also determines the properties of the anaphor. The
properties of the anaphor are used as constraints for filtering the entities from the
discourse model. Only discourse entities mentioned in the same or in the previous
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