You're welcome! I would love to see a Grad research project and/or group of entrepreneur enthusiasts put a graph like this together for most startup cities. You could probably equate some mathematical values to it as well to give an overall "startup friendly" score. That might be hard to objectify though. Keeping it open is also key. Think about the past few years and what has happened. Within 2 months after selling Mint, Aaron Patzer already made his first angel investment.

I'm hoping to construct one of these for Atlanta's clusters in finance and network hardware/software as well. In practice, they overlap a great deal.

And I agree - I think that not only can you rate startup friendliness this way, but you can directly measure 'startup wealth' and detect cluster emergence.

Russell, this is an awesome and very thorough visualization and analysis of Atlanta's cluster of security-focused companies. Luckily for Atlanta, the emerging convergence of TV-mobile-computer to a single device presents a tremendous need for more and more security products. Too, the threat of Internet terrorism does the same. Great job. Fascinating visualization.