“…Several spatial analyses appear to derive ambiguous results, notwithstanding the challenges of how to quantify them. For instance, 3D city models may be used for different kinds of visibility analyses, and therefore quantified in different ways: binary (a point in space is visible or not), distance (range) of visibility, the area or volume visible from a point, number of buildings that have visual access to a feature, and population that has visual access to a point (Cervilla, Tabik, Vías, Mérida, & Romero, 2016;Grassi & Klein, 2016;Wrózyński, Sojka, & Pyszny, 2016;Yu et al, 2016). Each one has different error propagation behavior (Biljecki et al, 2017).…”