Computational Aspects: How Landmarks Can Be Observed, Stored, and Analysed - Landmarks: GIScience for Intelligent Services - page 140

Fig. 5.4 The route investigated in [ 31 ] . White dots indicate differing selections between partici-
pants and model, black dots coinciding selection. Modified from [ 31 ]
Let us return to the example of Fig. 5.2 . If also accounting for advance visibility,
it turns out that for the given direction of travel, the Bank Austria building has
a higher salience value than the Haas building. Coverage for Bank Austria is
c D 1, and the orientation is also close to 1, while the Haas building is orientated
nearly completely away from the route. In principle, advance visibility needs to be
calculated for every landmark from every possible direction of approach to cover
for every possible wayfinding situation.
Klippel and Winter [ 26 ] presented a further extension of the salience model
that expands the aspect of structural salience. It accounts for the location of
landmarks along the route and the kind of wayfinding action that needs to
be performed. Since this is route-specific and not a general property of a
landmark candidate, their approach will be further discussed in Sect. 5.3 .
Raubal and Winter's formal model has been empirically evaluated by Nothegger,
Winter, and Raubal [ 31 ] (seealso[ 53 ] ). They implemented (partially manual)
measures for façade area and shape, color, visibility, and semantic attraction of
a building. Data for one route through Vienna's first district has been collected,
combining several data sources (again, a partially manual process); see Fig. 5.4 .
Using this data, for each intersection along the route the most salient landmark
was calculated. These were then compared with the results of a human subject