But if you could collect and analyze the opinions posted within the comments and questions, you could start to get a bead on the aggregate sentiment, sort of a Yelp for technology. That’s just what Gias Uddin, now a Senior Data Scientist at the Bank of Canada, looked at for his PhD thesis at McGill University. Along with his PhD supervisor, Foutse Khomh, Associate Professor at Polytechnique Montréal, determined a method to mine opinions on APIs and libraries from questions and comments posted on Stack Overflow.