# Complex networks, complex processes

I'm writing a book on my sabbatical. Or trying to, anyway. So I thought I'd publicise the fact so people can hassle me to keep at it.

I've been working on complex systems for a couple of years, especially on complex networks: things like the way people move through a road and rail network, or how diseases spread through social networks. It's a bit of a change from my previous work on sensor data interpretation, although not as much as you might think: I'm wondering whether we could combine sensing and simulation, to use sensors to confirm predictions or to drive and condition further simulations.

Getting into this area has been -- and is -- a head-wreck. It's both highly mathematical and highly computational. I understand the computing; the maths, not so much. Many computer scientists would have the same reaction, but conversely, so would many mathematicians: the maths would be familiar, the computing a challenge. So effectively in order to make progress you have to climb two learning curves simultaneously: some unusual and challenging mathematics about stochastic processes, simulated using cluster or cloud computing which poses a lot of challenges even for someone used to programming.

This is made harder by the research literature, though, which tends towards sparse mathematical descriptions, which is frustrating at two levels: the computing is probably interesting (to people like me), and it's hard to re-create the results when the computational approach underlying the graphs and results is unclear.

So with this in mind, and because I've never done it before, I've decided to write a textbook: *Complex networks, complex processes*. (No, I'm not very imaginative when it comes to titles...) The idea is to link the maths to the code, providing everything a research would need to get started with the maths and the computing. Since this is likely to be a book with, shall we say, *limited circulation*, I've decided not to bother with a publisher and instead make it completely open. You can look at the current state on the web here, download the sources, copy and run the code, or anything needed to get started.

It's a work in progress and it's not very usual to advertise books before they're in a fit state to be read, but I suppose that's just a part of open science: make the process visible, warts and all. It also means I'll hopefully get comments and encouragement to keep at it when it starts to fall by the wayside of other things I have to do. The goal is to get the majority done while I'm on research leave (until September), and comments on style, content, and progress will be most welcome.