Originally published in The New Stack Update.
GitHub and Stack Overflow do not represent a true picture of the world’s developers because not everyone uses these sites. Twenty-one percent of active GitHub users are in the Asia-Pacific (APAC) region and a 50,000+ person StackOverflow survey reported 22 percent of respondents coming from APAC. According to the World Bank, the Asia-Pacific region represents 60 percent of global population and 34 percent of GDP measured in US dollars. Two major publishers of developer surveys appear to model their samples based on something related to GDP and economic size. Although they use different sampling methodologies, Evans Data and Vision Mobile both report APAC to be 36 percent of their developer universe. So, yes, GitHub and StackOverflow undercount developers in Asia by about half.
The English language appears to be the biggest obstacle to using these GitHub and Stack Overflow websites to track software programmers. Beyond the academic wish to be accurate, this is important because these open source communities have become hotbeds of innovation.
Also published on Medium.