I'm a professor of mathematics at the University of North Carolina Asheville. I've also done a fair amount of consulting work over the years focusing on scientific and data visualization.
I'm happy to be part of the first Observable Ambassador's cohort.
Thanks! I've noticed some similar issues. Note that I set the minConfidence parameter to 0.4 in the facial detection, which is below the default of 0.5. I'm definitely not an expert in face-api, though! I'm pretty happy with how it works, overall, though.