Abstract The increasingly widespread application of drones and the emergence urban air mobility leads to a challenging question in airspace modernisation: how create safe scalable traffic management system that can handle expected density operations. Increasing number vehicles given volume enabling routine operations are essential for these services be economically viable. However, higher incre...

The relationship between Popper spaces (conditional probability spaces that satisfy some regularity conditions), lexicographic probability systems (LPS’s) [Blume, Brandenburger, and Dekel 1991a; Blume, Brandenburger, and Dekel 1991b], and nonstandard probability spaces (NPS’s) is considered. If countable additivity is assumed, Popper spaces and a subclass of LPS’s are equivalent; without the as...