Before revision:  Using more than 40,000 rigorously selected tweets (from over six million tweets collected using keywords) posted by over 20,000 distinct Twitter users , we adopt a human-guided machine learning framework to capture the public opinions on the potential vaccines for SARS-CoV-2 and classify them into three groups: pro-vaccine, vaccine-hesitant, and anti-vaccine.
After revision:  We adopt a human-guided machine learning framework (using more than 40,000 rigorously selected tweets (from over six million tweets collected using keywords) posted by over 20,000 distinct Twitter users , we adopt a human-guided machine learning framework to capture the public opinions on the potential vaccines for SARS-CoV-2 and classify them into three groups: pro-vaccine, vaccine-hesitant, and anti-vaccine.