My recent analysis of a common trait of Facebook profiles:

The peak in dp/dt is a Dirac delta function of the form

normalized by the scaling factor A to account for the fact that the integral of the Dirac delta is 1, whereas here it should be the total number of posts on the day of the peak. The dip below zero of dp/dt was when one hooligan's wall post about last night's debauchery was deleted.