Methods, apparatus, systems, and articles of manufacture are disclosed for adjusting a tuning event. Examples disclosed herein include determining an initial adjustment factor for a group of stations and a combination of metadata categories associated with panel data and census data. Examples disclosed herein further include determining a final adjustment factor for the group of stations based on the initial adjustment factor and a bias correction factor. Example disclosed herein further include adjusting weighted minutes of the tuning event based on the final adjustment factor, the tuning event corresponding to the group of stations and the combination of metadata categories, the adjusted tuning event to be credited to media.