I'm intrigued by the open data provided by StackExchange, and have been running some really interesting queries on the data.stackexchange.com page (using the Stackoverflow dataset).
In particular, I would like to dive deep on this claim taken from the Stackoverflow Developer Survey 2015 summary page:
In other words: what is the "value" of Stackoverflow? Not in terms of its own economic success or funding amount, rather how it affects its users, for example accelerating a pay increase for active users.
My ideal solution would be to correlate the activity of its users to some economic independent variable such as salary. Although the data on activity exists on Stackoverflow servers, this Salary data is not available (the downloadable StackOverflow Developer Survey dataset is anonymized).
What other proxies/datasets could be used to conduct such a study? I would use github commits but it is more oriented towards productivity, and there already is a great paper on this topic.