In responding to recent comments on a paper, I went looking for information on how prevalent Twitter is across the world.  Based on my work using geolocated images from Twitter, I had a sense that it tracks population and per capita GDP closely.  But I have not had the time to investigate the relationship more closely (tenure clock).  I was therefore happy to find I had downloaded, read, and forgot about a really cool paper, “Geo-located Twitter as proxy for global mobility patterns” by Hawelka et al. (2014).  That paper includes a lot of great descriptive statistics, the most appealing of which to me is Figure 2.

A screenshot of that figure is below.  It clearly shows a log-log linear trend between GDP per capita and Twitter penetration.  My initial exploration has shown that one should also take into account a country’s population when thinking about research.  Because most researchers will only have access to a 1% sample of tweets, the countries that produce enough data is probably a subset of the countries in the top right of the second panel of Figure 2.  Still, very cool work, and I would love to see if anyone has analyzed a multivariate relationship.