A few days ago, while looking for metrics that can be used to measure online communities, I found out that a company, Lithium Technologies, proposed a new index, Community Health Index (CHI).
...we identified the diagnostic and predictive metrics that most accurately represent key attributes of a healthy community: growth, useful content, popularity, responsiveness, interactivity, and liveliness. Although we uncovered other metrics that proved to be even more predictive of community health, the ones we selected as the basis for calculating the Community Health Index are readily available for most online communities across the industry...
I am wondering if someone tried to calculate this for Stack Overflow or other sites from the network and if so I would like to see some results and eventually your opinion regarding the accuracy of this index.
I know that the article is a little bit commercial but at least they propose a way to measure community health across different communities, of different sizes and ages, which is something valuable. If you know other ways of doing this, feel free to share your knowledge.