Communication Aspects: How Landmarks Enrich the Communication Between Human and Machine - Landmarks: GIScience for Intelligent Services - page 185

Then it is important to understand which specific bar and cinema are referred to . 6
This requires also an understanding of the context of the utterance [ 53 ] .
WhereIs solves this problem by forcing users to resolve ambiguities themselves.
It is possible to enter POI names as origin and destination (in the 'what' text
box), however, the user needs to additionally provide the suburb of the POI (in
the 'where' text box). Then WhereIs suggests a list of potential street addresses that
the input may refer to and makes the user select the appropriate one. This ensures
that WhereIs gets the context right, but on the other hand forces users to provide
information they possibly do not know.
Such context restrictions are typical for computational services. The above
argument is not a specific criticism of WhereIs, other well-known (web-based)
navigation services behave similarly. For example, Winter and Truelove [ 67 ] have
shown that while Google Maps allows for more free-form input compared to
WhereIs, interpretation of this input is often inadequate and requires users to
either adapt their input to the system interpretation or to put significant effort
in interpreting the results themselves. For example, Google Maps currently still
interprets any spatial relation as 'near'.
Although Winter and Truelove's analysis was drawn from the interpretation of
place descriptions, which are structurally different from landmark references as
shown before, many findings also hold for understanding landmark references. Also
in the context of place description research, Vasardani et al. [ 64 ] highlighted the
following issues:

￿ Official, authoritative gazetteers do not usually include unofficial and vernacular

place names, or temporary (replacements of) place names, such as event names
that are sometimes used synonymously for the location they are happening at.
This is in contrast to the popular use of vernacular place names, in particular
in familiar environments. Sometimes people may not even be aware of official
names. Thus, the restriction to official place names restricts a system's under-
standing of references to places and in turn restricts interaction possibilities with
the users.

￿ A sensible interpretation of spatial relations is important to understand place ref-

erences correctly. Clearly, taking every relation to mean 'near' is inappropriate.
Formal models for a range of spatial relations have already been investigated in
the literature (see Chap. 4 ) . In principle, these models enable a more adequate
interpretation of place references, however, the interpretation of spatial relations
is context-dependent [ 69 ] . Also, people's cognitive concepts of a relation may
differ from what is defined in a formal model [ 40 , 52 ] leading to diverging
interpretations of a place description.

￿ Places often are extended geographic regions with indeterminate boundaries.

This indeterminacy is hard to capture satisfactorily in computational models,
despite of several attempts [ 6 , 12 , 47 ] . Again, context and individual differences
aggravate the issue.

6 Even though in this example it may be sufficient to know which cinema is meant, assuming there
is only one bar in it.