Tuesday, January 17, 2017

GitHub Growth Appears Scale Free

In 2013, a Redmonk blogger claimed that the growth of GitHub (GH) users follows a certain type of diffusion model called Bass diffusion. Here, growth refers to the number of unique user IDs as a function of time, not the number project repositories, which can have a high degree of multiplicity.

In a response, I tweeted a plot that suggested GH growth might be following a power law, aka scale free growth. The tell-tale sign is the asymptotic linearity of the growth data on double-log axes, which the original blog post did not discuss. The periods on the x-axis correspond to years, with the first period representing calendar year 2008 and the fifth period being the year 2012.