These are my recent Pinboard.in links:
The ﬁnal stage of Krebs and Holley’s model, and its ultimate aim, is called a core/periphery social network. In this highly stable yet highly resilient social arrangement, which usually emerges after years of effort, a core of strongly affiliated hubs at the center of the social system is connected to a constellation of people and resources on the periphery, through weak ties. This allows for an efficient and natural division of labor: The periphery monitors the environment, while the core implements what is discovered and deemed useful.
There’s an interesting correspondence between unimodal p.d.f.’s on a metric space (like the reals), and distance functions. I will dig through this for amusement below, with some R code to generate the pictures.