Why is it "obviously true" (that lower probabilities of connection between than on levels)?
Because if it wasn't true then that would imply that V on different levels (as reached presumably by a canonical DFS tree // spanning tree) were closer (in terms of paths) than V on the same level, which would mean that those V should have "more likely" been on the same level (as however measured).
TL;DR - 'obviously true' because there's a level between them so (on average) of course!
Because if it wasn't true then that would imply that V on different levels (as reached presumably by a canonical DFS tree // spanning tree) were closer (in terms of paths) than V on the same level, which would mean that those V should have "more likely" been on the same level (as however measured).
TL;DR - 'obviously true' because there's a level between them so (on average) of course!