15 out of 20.
Spoiler: looking at the eyes and the lack of wrinkling around them is a pretty good tell. Oddly, it seems like other affirmative or negative gestures (nodding or shaking the head) don’t make a difference, in any predictable way. Also it seems like a lopsided smile (one side going up before the other, or one side more intense) isn’t a tell for a fake smile, even though it’s usually a contemptuous gesture (a sneer).
I’ve been fascinated by facial gestures and microexpressions recently. I scored poorly on a Autism spectrum test, and score much better on math and spacial recognition than verbal ability, so I’ve been wondering if I might have mild Asperger’s, and wanted to give my empathic acuity a test. I seem to be doing better than I should, though, if I did have Asperger’s.