Recently IEEE Spectrum published a paper on a refutation of Metcalfe’s law — an observation (not really a law) by Bob Metcalfe — that the “value” of a network incrased with the square of the number of people/nodes on it. I was asked to be a referee for this paper, and while they addressed some of my comments, I don’t think they addressed the principle one, so I am posting my comments here now.
My main contention is that in many cases the value of a network actually starts declining after a while and becomes inversely proportional to the number of people on it. That’s because noise (such as flamage and spam) and unmanageable signal (too many serious messages) rises with the size and eventually reaches a level where the cost of dealing with it surpasses the value of the network. I’m thinking mailing lists in particular here.
You can read my referee’s comments on Metcalfe’s law though note that these comments were written on the original article, before some corrections were made.