" Allen decided to dig deeper, measuring frequency of interactions against distance. “We could look at how often people communicated and see where they were located in relation to each other,” he says. “We could see, just through the frequency, without knowing where they sat, who was on each floor. We were really surprised at how rapidly it decayed” when they moved to a different floor. “It turns out that vertical separation is a very serious thing. If you’re on a different floor in some organizations, you may as well be in a different country. "

― Daniel Coyle , The Culture Code: The Secrets of Highly Successful Groups